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EVENT FORUM on GEOLOGY
EOLOGY of PHOSPHATE,
OLOMITE, LIMESTONE and
SF F. LIBRARIES
cial Publication No.17
ida Department of Natural Resources
ion of Interior Resources
au of Geology .
hassee,Florida, June,1972 '
^,,S" nw*. : *
SEVENTH FORUM on GEOLOGY
GEOLOGY of PHOSPHATE,
DOLOMITE, LIMESTONE and
Special Publication No.17
Florida Department of Natural Resources
Division of Interior Resources
Bureau of Geology
Preface, by H.S. Puri and B.J. Timmons ................................................ v
Keynote: War, by R.O. Vernon ................... ........ .. .................... 1
GENERAL INDUSTRIAL ROCKS AND MINERALS
Mineral Resource Law: The Spectre of Ecology, by D. Wallace Fields .............
Conflicting Land Use in the Florida Land-Pebble Area, by J.W. Sweeney ............
Sedimentary Fractionation and Industrial-Mineral Deposits, by Robert L. Bates . . .
Economic Geology of Florida Heavy Minerals, by Thomas Garnar . . . .
Origin, Diagenesis, and Structure of Bauxite Deposits in Southeast Alabama, by Glenn P. Jones
Sand and Gravel Exploration Methods, by Hill McDonald . . . . .
. . ... .. .
o ',. t
CLAYS, LIMESTONES, AND DOLOMITES; THEIR OCCURRENCES,
PROPERTIES AND USES
Fuller's Earth and Bentonite in Southeastern States, by Sam Patterson . . . ..... .. .. . .. 37
Vertical Variability in the Attapulgite Mining Area, by Charles E. Weaver and Kevin C. Beck . ..... . ...... 51
Absorption Characteristics of Opaline Clays from the Eocene of Georgia, by Robert E. Carver . . . ... .. 91
Future of the Kaolin Industry in Southeastern United States, by B.F. Buie . . . ..... . ...... ..103
Miocene Clay Deposits of Peninsular Florida, by F. Michael Wahl, and Bobby J. Timmons . . . .. ... ..109
Apatite Deposits East Central Bahia Brazil, by Gus H. Goudarzi, Pedro Antonio Couto, and Carlo Henrique de Souza ..... ..117
On the Origin of Dolomites, by Bruce B. Hanshaw and William Back . . . .... ........ . .139
Crystallochemical and Geochemical Comparisons of Recent With Older Dolomites, by Lynton S. Land,
Emilio Mutis, and W. F. Bradley ............................................... 155
Petrography of Carbonate Rocks by Image Analysis, by Richard D. Harvey and John C. Steinmetz . . . ..... ..161
Compositional Variations in High-Calcium Limestone Deposits in Western Kentucky, by Garland R. Dever, Jr. and Preston McGrain 171
ORIGIN, DIAGENESIS AND ECONOMIC GEOLOGY OF PHOSPHATE DEPOSITS
The Role of Florida Producers in World Phosphate Market, by Joseph L. Weaver . . . ... ...
Phosphate Industry and Environmental Control, by Bruce Congleton . . . . . . .
A Program for Ore Control in the Central Florida Phosphate District, by Richard C. Fountain and Michael E. Zellars
Hard-Rock Phosphate in Florida, by N.K. Olson ....................................
The Origin of Some Phosphatic Minerals in Coastal Plain Sediments, by John K. Adams . . . .
The Relationship Between Silicic Volcanism and the Formation of Some Sedimentary Phosphorites, by D.R. Lowe .
Georgia Phosphate Stratigraphy and Economic Geology of the Chatham County Deposit, by James W. Furlow .
. ... .181
. ... .185
. ... .187
. . .211
. ... .217
. ... .227
. . "
The Seventh Forum on Geology of Industrial Minerals was
held in Tampa, Florida, on April 28-30, 1971. Twenty-six papers
were presented during the three technical session of the Forum,
and are herein arranged in the order of presentation at the
The entire program was planned around the general theme:
"Geology of Phosphate, Dolomite, Limestone and Clay
Deposits", with the papers presented in three sessions. The
evolution of the art of mining from pick and shovel days to that
which supports the needs of a highly complex society has by its
very nature pricked the conscience of the
environmentally-minded public. Consequently, a paper by D.W.
Fields on "Mineral Resource Law: The Spectre Of Ecology"
presented a timely summary of the evolution of laws at local,
State, and Federal levels and their effect on the industry.
The public demand for better housing, cleaner air, purer
water, unlimited recreational areas, faster and safer highway
networks, and future urban planning is requiring multiple
land-use concepts, such as cities rising on mined-out lands and
being built with clays and limestones obtained from these
excavations. Our keynote address by Dr. R.O. Vernon
discussed some of the problems associated with public awareness
of the environmental issues and possible recourses.
A second session was devoted mainly to "Clay, Limestones,
and Dolomite, and Their Properties and Uses". With phosphate
being Florida's greatest valued mineral product, nine papers
comprised a session on the "Origin, Diagenesis, and Economic
Geology of Phosphate Deposits".
The presentation of papers was followed with a one-day field
trip through the Florida Phosphate District where the
participants had a first hand opportunity to examine the
geologic occurrence and mining operations of International
Minerals Corporation. The Bonnie Phosphoric Acid Plant of C.F.
Chemicals, Inc. was also visited for a first-hand look at the "wet
process' phosphoric acid manufacture. Gratitude is expressed to
the management of I.M.C. and C.F. Chemicals, Inc. for making
their facilities available to use, with a special note of thanks to
I.M.C. for preparation and printing of the field trip guidebook.
Many persons have contributed to the success of the Forum.
We would like to express thanks to the members of the Program
Committee for soliciting timely papers, to the contributing
authors for their cooperation, and to the Arrangement
Committee for the meeting and registration.
H.S. Puri, Chairman
BJ. Timmons, Co-chairman
Seventh Forum on Geology
of Industrial Minerals
KEYNOTE ADDRESS: WAR
Robert O. Vernon
Chief, Bureau of Geology
I extend the warmest kind of welcome to the "Friends of the
Earth," the "Everglades Coalition," "Conservation 70's," "Sierra
Club," Defenders of the Environment," various organized lovers
of birds and beasts, and to those trying to earn a living and
You are well aware of the citizen forces pitted against each
other today. "Affluence versus underdevelopment,"
development against the 'concerned citizen' or 'concerned
scientist'; the conservationist and the preservationist competing
with the producer and the extractive interest. In Florida the
trick is to learn to spell ecology and pronounce ecosystem and
you graduate as an expert in the field of environmental
With apologies to Bob Brumfield of the Cincinnati Enquirer,
as a professional, I'm thinking seriously of becoming an
environmental dropout and telling the rest of the world to go to
In doing so I'd say "Look you freaky ingrates, we're beating
our brains out to provide you the best water in the land, to
take-up, treat and recover your wastes and make them useful, to
make your homes warmer in the winter cooler in the summer,
because you asked for it.
'We've provided you the raw-mineral resources for stronger
and lighter building products, so that structures could be built
higher and more safely. We've nurtured you from the nutrients
taken from the earth so that we are the best fed and clothed
people of the world and have moved to restore the land to higher
values than the original raw earth, because that's our business,
done at your insistence.
'We've provided you with the best park systems, guaranteed
you potable water long into the future, developed long range
electrical and fossil fuel plants for production of heat and power,
heated your water, provided landscaped arterials that are
unexcelled and that have increased your crop yields, outlined
and mapped water crop areas, eliminated infestation and disease
because that was your desire.
'We've done just about everything for you except tie your
lousy shoes, and now you sit around on your fat can, too lazy
and insensitive to put out a few bread crumbs for the sparrows,
and you blame us because the East African Blue-billed Yodeling
Crane is almost extinct.
'Tell you what, Mac. ..., why don't you waddle off
somewhere and feel warm alligator eggs."
The appointed defenders of America helped to form, if they
didn't indeed shape up Parkinson's newest law, "The law of
delay" -which reads, "Delay is the deadliest form of denial."
Knowing the difficulty of organizing a needed public works
project, or a new minerals extraction venture, getting it
authorized, obtaining funds and keeping the local enthusiasm
alive, such organizations can quite sincerely view with alarm the
effects of the search for hydrocarbons, the construction of
power plants in warm areas or the processing or mining of
minerals will be on the environment. The benefits are never
mentioned, as if they didn't exist; data and facts are often
misstated and misinterpreted or so confused as to be
meaningless. Only those adverse ones are cited. Such curbstone
professionals in fact, sell their professionalism cheaply and cost
progress dearly-delay, lie and confuse until all resource
development becomes stagnant.
We can no longer afford to construct monumental dedications
to the futile effort to preserve a passing way of life, with little to
no benefits to the people. A works project today must meet a
multipurpose use or we can't afford it-regardless of the pressures
to preserve the cut-over, channelized, snagged and polluted
"primitive ecosystems" of the nation.
Florida, lovely state that it is, has the purest of water, the
freshest of breezes, broad reserves of needed mineral resources,
largely unsullied beaches and waterways, yet at the same time, it
has the highest growth rate in the continental United States. The
demand to clean our environment meets head-on with the need
for raw mineral resources.
Some citizens have forgotten, or have never known, that man
is part of the evolutional sequence and competition between
species is fierce and will continue-the rapid expansion of the
human species drains the energies from many other species, uses
up their nesting grounds, makes it difficult for them to
reproduce, to feed and to exist-species will continue to be
endangered and to disappear as man continues to over-populate
and dominate-unless we control our own passions for
reproduction, selfish possession, waste and failure to purge our
environments of unneeded and toxic gases, liquids and solid
wastes. Man, our most corrosive geologic agent today, has
permitted his need for, and use of, raw mineral products
virtually to exhaust his requirements for the esthetics of
You, as earth scientists, must provide the means and the
forum necessary to express the greater need for mineral and fluid
resources, to express the boundaries for utilizing these for
reclamation, reuse and restoration of disturbed lands. Who, but
you, are positioned to give direction to the adequate distribution
of these resources and the means of forming corrective input
relative to an improved environment.
Become an activist, even a radical for conservation (wise use),
attend civic, commission and state committee meetings and
demand that your views be given consideration. Stand for public
office--but let's have a beginning at continuing America's
affluence and at the same time purging it of wastes.
To some the expertise possessed by earth scientists is the basis
of environment. Yet, I find that increasingly in the dialogue now
occurring between the preservationist and the developer, in the
control of pollution and improvement of the environment, the
earth scientist is not meeting his responsibility to participate in
town meetings, to lead the awareness-student groups, to advise
the Legislature and other public bodies, even to the point where
we no longer wear the white hats and we are considered part of
the problem rather than the basis of the solution.
Perhaps the difference arises out of two diametrically opposed
needs of society, to acquire raw minerals and to reverse the trend
of a rapidly deteriorating environment brought about partially
by search, discovery and use of resources and reserves. Obviously
the search, discovery, extracting, processing, and use of minerals
(including the fluid resources) of the past have been wasteful and
destructive of the environment and must be regulated for the
common good. It is no small wonder that we find the Florida
Legislature introducing legislation that seeks to forbid the
drilling for oil within 12 miles of the shoreline, upon the
wetlands, and it is seriously considering the limiting of mining.
The frequency of the conflict of affluence with environment
GEOLOGY OF INDUSTRIAL MINERALS
indicates that earth scientists are failing to alert the people of
their dependence upon resources of raw minerals and to the need
to produce these, and to clean-up afterwards.
If dinosaurs were part of contemporary life and became
totally unsuited to cope with their environment, as they did
during the Jurassic, I would assure you there would be
instantaneous outcries from the preservationist, that man was
ruining the environment and an appropriation must be made by
the Congress to be used to construct a habitat and maintain the
bog humidity and large plant growths so necessary to save the
dinosaurs, "the endangered species of that time and that place."
There was a time when we gave very little thought to mining
of fertilizers which are necessary to our survival. Why worry
about soil or nutritional additives when we had but to clear
another "40" and let the last cultivated one lay fallow for a few
years. Suddenly and inevitably, our tillable 40's became scarce.
The next forty had to be revitalized and pridefully this was sired
by our Florida phosphate industry. It has indeed been the sire of
a prolific dam as that additional forty has been reborn time and
This propagation has not been without pain, and as the farm
grows older the associated ills become greater and more
frequent. When the prairie, floodplains and hills were converted
to farms, the response of the people began to be heard and it
now resounds throughout the land. Through meetings such as
this, and as a perusal of your past proceedings would
substantiate, your direction is devoted to supplying the
necessary minerals, while meeting the demands of a complete
recovery period, leading to total land use through reclamation
and aesthetic planning. A period, an era, a crossroads in time,
where re-evaluation of our most important resources is in
keeping with the need.
Demand, as now being expressed by America, is dependent
upon many other functions. Demand for a new type of housing,
demand for cleaner air, purer water, less noise. Demands that
must be met, while hopefully, not initiating new problems.
Demands of an advanced technology which must be supplied
through alloying, utilization of by-products, recycling of used
items, and, certainly discovery of new resources and reserves.
Fortunately, these demands are not limited to those of us that
practice in the physical sciences, but they encompass us as
individuals, parents, civic leaders, corporate members, club
members and charter members of the human race, supposedly
endowed with that singular ability to cope with the total
Supply must nearly always equal demand in a healthy
economy, and therefore, makes it understandable to geologists,
distributors, salesmen, contractors, and others through
fluctuations in value. Our forests, through wise and efficient
management, are renewable within time limitations. Our air and
water supplies are not diminished, but are rendered temporarily
unusable at times, due to our short-sightedness. Not so our
mineral resources; the supply is finite, but its wise utilization can
expand its life until technology provides adequate substitutes
and/or extended life periods. Demand and supply upgrade our
professional capabilities by taxing our ingenuity. Our ingenuity
yields, with more efficient planning, bountiful harvests in the
fields of usable by-products, and recycled economic wastes.
You are now facing an aesthetic variable of proportions never
before faced by the minerals industry, industrial or otherwise.
The odds are definitely against your having precedents or
established company policy to guide you on these new, "gray"
areas. Therefore, a "new frontier" may be present in the
minerals industry, fostered by you and me, and domesticated
only through us.
To those of you intimately associated with the petroleum
industry, you admit with lip-biting reluctance, that the success
ratio of the 60's was approximately the same as that of the 30's.
This, on the surface, would not speak well for the scientific
community, but those of us who derive our paycheck from
providing the raw resources recognized that a less affluent
society reaped the benefits of easy finds and who can say that
this was not proper. A young, struggling republic seemed to have
been nurtured by Mother Nature herself as she readily gave up
her riches to those so needy. Demand, has virtually exceeded our
ability to supply and meet the demands for improved aesthetic
The basic framework for solution of the "war" between
resources and aesthetics must be: (1) complete and systematic
recovery of the known mineral resources; (2) multiple
simultaneous and/or sequential land use where possible; (3)
adequate planning with consideration for all resources, now or
here-in-after affected: (4) intensive and extensive exploratory
work to uncover new reserves; (5) design of plants, mines, etc.,
with a smaller profit margin in mind and vastly extended
production life; and finally, (6) an honest awareness of the total
effect of our endeavors.
These are not insurmountable tasks and are consonant with
the faith that nurtured this nation. They are simple challenges
which spur us to new heights of achievement.
We here in Florida are experiencing a growth rate unexcelled
in our history. Fortunately for us, the minerals needed to
support this growth are present in fantastic amounts. Supplies of
construction materials, hydrocarbons and phosphate are found
in abundance throughout much of the state, but their recovery is
being considered more carefully than ever before. An apparent
reckless high volume, extraction period is cushioned by a period
of sincere considerations for ore tenor, possible air and water
pollution problems, noise abatement, landscaping of spoils, and
complete utilization of all possible products, both primary'and
Florida has 100% open pit and dredge mining with a resultant
maximum modification of the surface. No communications gap
exists between those concerned citizens and the extractive
minerals industry. Industry hears about the problems it creates
in no uncertain terms, and even those of us in administrative
posts within the government are held equally responsible for
these acts of degradation. These acts are defined too often, on
relativity. If an evident change occurs without local benefit, then
it is bad. If, however, these changes are made to afford large
numbers of human beings a higher standard of living, then they
become good. Such is the role of the mineral producer today.
Your job has taken on a new dimension, and this, according to
Peter Flawn, is the creation of a "realistic social attitude."
Society must be made to realize that a continuing supply of
minerals, including water and energy fuels, is necessary to
perpetuate our way of life. We can and we must "have our cake
and eat it too." Preferably, the creation of this realistic social
attitude toward our mineral resources, would be initiated by
society itself. ..It would have us pause to consider its population
trends, its economic path, and its environmental requirements
and necessities and temper its demands accordingly. A return to
a less affluent way of life is a probability but so many of us are
too old, too tired, or too proud to accept what is commonly
believed to be regressive action.
However, "Government itself", being the ultimate steward of
.he land, decrees that, the severed minerals shall be taxed and
the land restored, a land use plan be filed before extractions
begin and all must combine to supply the community's total
needs. Utopia? Hardly!! But certainly a potential improvement
in the ecology and environment would assist those responsible
for supplying our mineral needs.
Those of you employed directly with the production of our
industrial minerals, may now occupy one of the most influential
VERNON: KEYNOTE ADDRESS: WAR
positions since the time that land reclamation was recognized as
necessary, by providing the necessary professional knowledge to
meet The Challenge.
The continued success of our way of life depends upon your
abilities, both in a development and a discovery sense. Your
ability to orderly, efficiently, systematically, develop our known
mineral resources and discover new reserves, substitutes, and
methods of complete utilization of all resulting products, will be
the measure of your success.
Your geologic techniques must be re-examined for clues
heretofore too hidden to be of significance, your mining
practices must continue to utilize the common sense, "use-it-all"
philosophy inherent in many of your mine foremen, and you
must assist your training institutions, .tell them what you need
in the way of new graduates. Compel them to develop minds to
the degree of practical competence required to solve practical
I do not want to infer, however, that this entire task is yours
alone. Our present Lt. Governor, when he was Secretary of
State, made a statement to the Southern Water Resources
Conference in 1968 at Miami Beach. "You scientists have told us
what you need. Now it is up to us as politicians to devise the
'how' and provide that legislation." So they, the politicians,
must provide the instruments and the framework that will allow
the minerals producers to mine or drill in the ways now being
MINERAL RESOURCE LAWS: THE SPECTRE OF ECOLOGY
D. Wallace Fields
Carlton, Fields, Ward, Emmanuel, Smith & Cutler, P.A.
Attorneys at Law
Increasing public pressure and demands from various tiers of government have generated a legislative maze of statutory and
administrative requirements facing industries involved in mineral extraction and processing. Each tier of government has
asserted concurrent jurisdiction and threats of harsh measures if industry does not satisfy all requirements.
In the field of water pollution control, federal requirements have increased, carrying with them increasing techniques of
enforcement ranging from injunctions through criminal penalties. Federal laws have required that states formulate water
quality standards as an adjunct to federal regulation. Florida has reacted with the Water Pollution Control Act of 1967. This
act incorporates state water quality standards and permit requirements for any installation constituting a potential source of
pollution, and provides for civil sanctions as well as injunctive relief.
The federal government has utilized an 1899 law to require a permit for discharges into navigable waterbodies a term
which has been judicially defined to include any watercourse capable, after reasonable improvement, for use in the
transportation of waterborne traffic. Failure to secure these permits can result in the issuance of an injunction or civil or
criminal penalties. The Corps of Engineers will not issue these permits without the approval of the discharge by state, local and
other federal agencies.
Air pollution similarly is regulated by a multi-tiered network of laws and administrative standards. Federal regulation has
increased from early research support in the 1950's through the development of Air Quality Standards and their enforcement
by large fines, injunctions, administrative conferences and public hearings. Florida regulation, under the Florida Air Pollution
Control Act of 1967, parallels federal law but grants concurrent regulations, requirements and enforcement tools to local and
Although previous state regulation was minimal, consisting only of three acts passed in 1891, 1899, and 1911, in the future
the mining industry will have to contend with this increasing network of ecological requirements. It is recommended that the
industry take the initiative by involving Florida in the Interstate Mining Compact, as well as seeking the passage of a state
reclamation law funded by a severance tax.
MINERAL RESOURCE LAW:
THE SPECTRE OF ECOLOGY
The world has turned to the care and cure of the environment.
The determination of its people to have fresh air to breathe and
pure sparkling lakes, rivers and estuaries to enjoy once again, is
evidenced by the enactment of new laws, many laws, with
"teeth" in them, to insure that result. The people have spoken
and industry must listen, before it is too late.
If industry does not begin the cure itself, departments,
bureaus and commissions of the United States, the States or
local authorities will do it for them, at such great cost that many
industries will not be able to survive.
What has sparked this great demand for change? Those who
are most vocal were not born until after our country became
polluted. Perhaps the answer lies in the fact that during the last
quarter-century our economic system has gone through the
greatest change in all history. We worked our way out of the
depression of the thirties and have kept on working, to the point
where now our people have such an abundance in goods and
services that our appetites have been satisfied. Some, therefore,
have become complacent. They have turned away from our
competitive heritage and taken up the pursuit of humanistic and
social goals. But, the spark generated by those few has lighted a
fire and the fire has spread and spread to the point where the
people are now mad and determined. They are willing, even
anxious, to put pollutants out of business. Evidence of this fact
is appearing in laws, harse laws, that recently have been passed
by Congress and by our State Legislature. As I outline these laws
to you, please notice the pattern. Congress, in its laws, threatens
the States by saying, if you do not pass and enforce laws to
abate pollution we will assume jurisdiction and do so. Our
Legislature has then passed laws saying to the Counties and
Municipalities, if you do not pass and enforce ordinances and
regulations to abate pollution, the State will do so. The Counties
and Municipalities, jealous of their own jurisdiction, have passed
ordinances and regulations to this end. On the assumption that
the lower jurisdiction in each case would take up the fight, and
to insure this result, the Congressional Acts and the Florida laws
are structured with interweaving tiers of concurrent jurisdiction.
At each tier there is a right to force you to act in a preferred
fashion, with the threat of tough and harsh sanctions if you fail
to act. Hence in the future it will be necessary to satisfy the
environmental desires of your city, county, state and federal
government. Keeping but one of these happy will not be enough.
Federal requirements in the field of water pollution began in
1948 with passage of the Federal Water Pollution Control Act.
The basic act, amended four times since then, comprises the
present federal water pollution control program. Administration
has changed from one federal bureaucracy to another. Originally
placed in the Department of Health, Education and Welfare, it
was transferred to the Department of the Interior in 1966, and
was placed in the newly created Environmental Protection
Agency last year.
The heart of the Act is the enforcement provision. Broadly
speaking, the Act provides for proceedings to abate any
pollution affecting interstate waters, or waters which might be
found to be navigable, or even any waters which affect other
navigable waters. State abatement action is encouraged, with the
underlying threat that the federal enforcement is imminent
without state action.
The Act called for formulation of water quality standards and
a plan implementing the standards; quality control and
enforcement plans were to be established by the states. If the
state did not submit acceptable standards within one year of the
Act, the federal government would have determined the water
standards. If material discharged into the water reduces water
GEOLOGY OF INDUSTRIAL MINERALS
quality below the standards set, a federal court could enforce the
act. In addition, the act provides for abatement proceedings
involving conferences, hearings and court action.
The 1967 session of the Legislature passed the Florida Air and
Water Pollution Control Act. Although authority to enforce this
act was initially in the hands of the Cabinet, in 1969 the
functions, powers and duties of the Cabinet sitting as the Florida
Air and Water Pollution Control Commission were transferred to
a new Department of Air and Water Pollution Control. This
should provide an even stronger impetus for forceful and strict
The Department adopted Rules satisfying the federal
requirements by establishing quality standards. Now the state
can compel any person engaging in an operation that may result
in pollution to file reports to be used in determining methods for
controlling or preventing such pollution. The state has
established a system of permits regulating the operation,
construction or expansion of any installation that might be a
source of pollution. Enforcement is provided by authorizing a
civil penalty of $1,000 a day for violation of any order. In
addition, violation of any order is a misdemeanor punishable by
a fine of up to $5,000. Each day of violation constitutes a
separate offense. Failure to pay the fine can result in loss of the
right to carry on business in Florida.
The Department of Air and Water Pollution Control has the
control and supervision over underground water, lakes, rivers,
streams, canals, ditches and coastal waters insofar as their
pollution may "affect the public health or impair the interest of
the public." The legislation authorizes both temporary and
permanent injunctions. The act, as amended in 1970, authorizes
the state director to procure an injunction if he finds that "a
generalized condition of air or water pollution exists that creates
an emergency requiring immediate action to prevent harm to
property or to animal, plant, or aquatic life."
The rules of the Department of Air and Water Pollution
Control provide that when certain elements occur in any amount
in any individual body of water, they shall be suspected of
degrading the quality of that particular lake or stream;
phosphates, nitrates, sulphates, sulphides and free mineral acids
are included in this list of constituent elements.
The state statute further authorizes local pollution control
programs. These programs must satisfy state requirements, but
are authorized to go beyond the state requirements to provide
stricter and more extensive regulation. In addition, the state
Department may authorize area-wide pollution control
programs. The state Department specifically is barred from
exercising jurisdiction "over local acts of a stricter or more
Unsatisfied with the rate of progress under these federal and
state statutes, the President in December of last year announced
a new program of enforcement utilizing a Federal act called the
"Refuse Act" that had been in existence since 1899. The Refuse
Act prohibits the discharge of any refuse matter into navigable
waters or tributaries, except that flowing from streets or sewers,
without a permit from the Army Corps of Engineers. Violators
of the act are subject to criminal prosecution and/or a civil
injunction. Decisions of the United States Supreme Court have
construed this act to include pollution as well as obstruction to
navigation. A recent decision by the federal Court of Appeals for
this Circuit hints that the act might have possible application to
any pollution affecting any watercourse which might affect a
navigable water body or might affect interstate commerce.
The new permit program announced by the President will
require all present and prospective dischargers to obtain a permit
under the Refuse Act. A deadline of July 1st of this year was set
for the permit applications. Before a permit may be issued, the
Corps of Engineers will require state acknowledgment that the
discharge will be consistent with applicable water quality
standards. These could include both state and local standards. If
the water receiving the discharge is subject to federal jurisdiction
under the Federal Water Pollution Control Act, the state
recommendation relating to the permit will be subject to further
review and approval by the Environmental Protection Agency.
No permit will be issued without the recommendation of either
the Environmental Protection Agency or the appropriate state
In the realm of air pollution it is probable that Florida and
most other states would not have created a regulatory air
pollution program had it not been for federal impetus. Federal
activity in the air pollution field began in 1955 when Congress
funded the Public Health Service in the Department of Health,
Education and Welfare to do research in air pollution control.
Pressures for further federal activity prompted the enactment of
the Clean Air Act of 1963.
The Act evolved from a Senate committee study showing that
the states, other than California, were doing little to cope with
air pollution problems. Although repeating the principle that the
prevention and control of air pollution was the primary
responsibility of state and local governments, it incorporated
provisions authorizing a stronger federal role. It provided, among
other things, for the development of air quality standards by the
Department of Health, Education, and Welfare, to be used in
local enforcement and in federal abatement proceedings.
In 1965 the act was amended to authorize Health, Education,
and Welfare to make findings and recommendations following
public conferences on potential air pollution. In 1967 Congress
passed the Air Quality Act setting in motion a regional approach
to establish and enforce federal and state air quality standards.
According to that Act, the Secretary of Health, Education and
Welfare designated air quality and control regions within a state
or within an interstate region, and promulgated air quality
criteria for those regions. The states were entitled to set
standards limiting the level of pollutants described in the criteria;
if the state failed to do this, the Secretary was empowered to set
the standards. After the states developed air quality standards,
they had to establish comprehensive plans for implementing such
Enforcement under the 1967 amendments included the use of
conferences, recommendations by the Secretary of Health,
Education and Welfare, hearing board findings and
recommendations, and enforcement suits. The act also
authorized, where pollution is presenting "imminent and
substantial endangerment to the health of persons" and state or
local officials have not acted, the Secretary of Health, Education
and Welfare could request the Attorney General to institute suit
to enjoin any contributor to such pollution.
Amendments to this act in 1970 made it even stronger and
harsher upon the polluter of the air. The Act, as amended, is
now enforced by the Environmental Protection Agency. The
new act set up dual ambient air quality standards, one relating to
public health and the other to public welfare. The amendment
permits states and local government agencies to establish more
stringent standards than national criteria, and to shorten the
deadline for attainment to less than the three year federal
period. Furthermore, the federal government now shall identify
specified hazardous pollutants, and shall determine the emission
levels for those pollutants which will insure an ample margin of
safety for the public health. New facilities emitting any of these
pollutants may be prohibited or constructed only if they meet
such standards. These hazardous air standards, within the next
two years, will be applied to existing sources of air pollution.
If the state fails to enforce the federal or state standards, the
federal Environmental Protection Agency may enforce those
requirements through administrative orders or court action.
Knowing violations of an Environmental Protection Agency
order or of federal standards shall be punishable by a fine of not
FIELDS: MINERAL RESOURCE LAWS
more than $25,000 per day of violation or by imprisonment for
not more than one year. For second or subsequent violations the
fine is not more than $50,000 and imprisonment for not more
than two years.
Extensive litigation under the federal act may be expected
because of the 1970 amendment authorizing suits by citizens
claiming to suffer the adverse effects of the pollution. Those
citizens can sue the government at all levels for failure to
prosecute the pollution standards.
At the state level powers similar to those mentioned earlier in
conjunction with water pollution are available where the state
feels that an activity is creating air pollution or might generate
further pollution. Construction permits for emissions into the
atmosphere are required. Local regulation of air pollution is
authorized, so long as that regulation is more stringent or as
stringent as the state requirements. The enforcement tools
available to the Department of Air and Water Pollution Control
for air pollution are the same as those mentioned earlier in the
realm of water pollution.
Regulation does not stop here. In an attempt to define
national policy for the environment, Congress in December of
1969 passed the National Environmental Policy Act. The Act
declared a national policy of preserving and protecting the
environment and required any and every federal program to be
evaluated in terms of its impact upon the environment. This
affects grants which our state might now be receiving or could
receive in the future from federal sources. Furthermore, the Act
is to be applied in conjunction with other federal statutes, so as
to provide a further standard and check upon state regulation.
The breadth of this new act is indicated by the fact that it was
the vehicle utilized by the President and the federal courts in
stopping the construction of the Cross-Florida barge canal.
Further regulation may evolve. On January 12th of this year,
the Acting Secretary of the Interior, in an address before the
American Mining Congress in Washington, D.C. predicted
government regulation requiring recovery of everything that can
be extracted in the mining and refining process, not just what
could be recovered at the lowest price. The Secretary predicted
that mining interests would have to prevent pollution drainage
and to reclaim the land and plant it with grass and trees after
use. In terms of the air affected by mine operations, he projected
that industry will have to clean the air or convert it to elements
that are compatible with nature's recycle. Water used in mining
and refining operations will have to be purified before it is
returned to any surface or underground water body.
Prior to the passage of the Florida Air and Water Pollution
Control Act in 1967, the mining industry lived in complete
harmony with nature insofar as the regulatory laws of Florida
were concerned. In fact, for the period between 1911 and 1967,
or 56 years, not a single law was enacted or enforced which
directly affected mining activities pollution or otherwise. The
only laws on the books during all those years were the following:
In 1911 Ch. 533 F.S. was enacted. This law made it unlawful
for any person to permit waste, wash or debris to escape from a
mine into any of the streams and rivers of the State. However,
the act goes on to say that the escape of water slightly discolored
shall not be construed as the escape of waste, wash and debris.
In 1891 Sec. 768.10 F.S. was adopted. This law made it
unlawful for any person to leave a pit or hole open which had a
depth or breadth of more than two feet, unless the same was
enclosed by a fence to prevent horses, cattle or other domestic
animals from falling into the same. The act goes on to say,
however, that the law shall not apply to persons engaged in
mining operations so long as those operations continue.
In 1899 the Legislature passed Sec. 828.11 F.S. which
required all phosphate mining operations to be fenced where the
waste had collected in quantities sufficient to bog up cattle,
sheep, hogs, horses and other animals. The penalty for violation
was a fine of not less than $10.00 nor more than $100.00, and
the violator was also to be held liable civilly to the owner of any
livestock that may be lost, killed or injured as a consequence of
non-compliance with the law.
So, from the beginning of time until 1967, the only Florida
laws directly governing mining operations were the three simple
little laws I have just mentioned.
With startling suddenness, laws have now been passed making
the mining industry more strictly regulated by Federal, State and
Local authorities than the liquor industry, small loan companies,
banks, trust companies, food processors and many other
businesses and institutions which for the past fifty years or more
have been under the watchful eye of beaureaucratic enforcement
Boards and Commissions.
If the mining industry cannot survive under our present laws,
and I forecast that it cannot, then what can it do about it? The
answer is inescapable. The industry must in great haste obtain
the passage of laws in Florida which will largely permit the
industry to police itself. This can be accomplished if all mining
interests will join together and obtain the passage of a statute
making Florida a member of the Interstate Mining Compact.
Next, agree to the passage of a Reclamation Law under the
jurisdiction of a Board or Commission composed of a
cross-section of people aware of the nature and problems of the
industry, mixed with representation from the Florida
Department of Natural Resources and Air and Water Pollution
Control, to make the Commission membership consistent with
the previous desires of the Legislature. Finally, agree to a
severance tax to support the Commission; such a tax law should
contain a provision that the tax is in lieu of all other ad valorum
taxes which might be otherwise imposed because phosphate or
other valuable minerals were located beneath the surface.
Only three states have joined the Interstate Compact so far -
Kentucky, Pennsylvania and North Carolina but when the
Federal, State and local authorities begin strict and harse
enforcement under the existing legislation, I am sure that many
more states will join the compact and agree to the less onerous
laws which the Compact fosters.
You will ask the question whether joining the Compact and
agreeing to Reclamation and Severance Tax Laws will relieve the
industry from complying with the existing laws. The answer is
no, it will not. But, if the industry will agree to be governed by
Reclamation Acts and laws fostered by the Compact, it will have
a good chance somewhere down the road to obtain the passage
of Laws reducing the impact on the industry of existing
legislation. At the very least, it reasonable can be anticipated
that the governing authorities will act with tolerance in enforcing
those laws against an industry that is doing a good job in policing
I fully recognize what a traumatic effect forced reclamation
would have on the industry. But it is to be hoped that land
values have increased to the point where reclamation is
economically feasible. We would also hope that an "in lieu of"
severance tax would not, when added to real estate taxes,
increase the amount of taxes now being paid.
The lawyers of Florida are self-disciplined. Every practicing
attorney must belong to the Integrated Bar of Florida and the
Bar prosecutes violators of the rules and regulations it
established to govern the conduct of its members.
Penalties range from private or public reprimand for minor
infractions to disbarment for major offenses. Many Florida
lawyers have been disbarred.
A case is brought against a violator much like a criminal is
prosecuted in court. A lawyer is appointed to prosecute, a
referee is appointed as a trier of the facts and to make
recommendations to the Board of Governors of the Bar. The
Board of Governors reads the record of the trial, determines the
guilt or innocence of the accused and fixes the punishment, if
any. If a lawyer is found guilty by the Board of Governors, he
may appeal his case to the Supreme Court of Florida sitting in
judgment as the final authority.
GEOLOGY OF INDUSTRIAL MINERALS
I can assure you that more lawyers are disciplined in this
manner than would be if disciplinary laws were established by
the Legislature and those laws enforced as criminal charges.
The mining industry could govern itself in like manner if it
chose to do so. Self-enforcement can take the place of the
quagmire of conflicting, confusing laws and regulations.
The question then is: Who shall govern the governed?
LAND USE CONFLICTS AND PHOSPHATE
MINING IN FLORIDA
Bureau of Mines, U.S. Department of Interior
The Florida land-pebble mining industry of central Florida was examined to identify trends in land use; conflicts in land
use; and the effect of the conflicts on mineral resources.
Many conflicts exist in the study area, such as conflicts with other users of land resources and land surface; conflicts with
high revenue land users; conflicts for land surface in urban and suburban areas; and conflicting restrictions concerning
utilization. Projections are made showing that lands in phosphate company ownership are expected to be made available to
help meet the need for future urban expansion in the study area.
Some phosphate resources have been lost due to land use conflicts, however, most of the resource loss has been small. Land
use conflicts and phosphate mining are reconcilable and considerable progress toward their maximum and multiple use of land
and mineral resources can be resolved through farsighted planning based on factual data.
As part of a Bureau of Mines national study on mineral
resources and land use conflicts, the Florida phosphate mining
industry was examined to identify trends in land ownership and
use, conflicts in land use, and the effects of the conflicts on
phosphate resources. The Florida land-pebble phosphate district
is an important segment of the national mining industry and
produced about 79 percent of the total United States marketable
production of phosphate rock in 1969.
The area of study is the Central Florida land-pebble phosphate
district comprising about 2,000 square miles in Polk,
Hillsborough, Manatee, and Hardee Counties, Florida. Of this
area about 520 square miles, or 26 percent, is controlled by the
phosphate industry and an estimated 200 square miles is
classified as urban and suburban land. The five major cities in the
study area are almost completely surrounded by phosphate
industry holdings, making the phosphate industry an important
controlling factor in the future use of this land. The population
within the study area was about 750,000 in 1970 and is
projected to be over 900,000 by 1975 (a 20 percent increase);
about 60 percent of the people live in urban portions of the
study area, indicating that additional land will be needed for
urban expansion. The remaining 1,280 square miles of the area is
mainly in private ownership and is used for agricultural purposes.
There are many land use conflicts in this section of Florida;
the population of rural areas and cities is growing rapidly, and
the need for land for both urban and suburban development is
TRENDS IN LAND OWNERSHIP AND USE
Let's examine the present trends in land ownership and use
for the following categories: urban and suburban lands, mineral
lands, agricultural lands, and public, private, and recreational
There is a need for additional land in the study area for urban
and suburban use. Until recently, the cities had enough land for
expansion, but they have now almost reached a saturation point
and additional land for residential and industrial growth is
needed. The phosphate industry is in a position to make this
land available, and present and projected trends in land use
depend on cooperation from the phosphate industry, since it
holds the key for future urban expansion. The industry believes
there can be compatible development between urban areas and
industry; they have pledged that they will try to make lands
available to the cities. Nevertheless, dependency of some of the
1Chesson, M.W. Talk given to the Florida Conservation Workshop,
Florida Southern College, Lakeland, Florida, July 6, 1966.
urban areas on land being made available by the phosphate
industry could retard growth rates.
The phosphate industry maintains mineral exploration
programs to improve its reserves position. Exploration has
moved southward into Manatee and Hardee Counties where both
established and new companies have purchased phosphate
reserve lands. High grade deposits in the central part of the
district in Polk and Hillsborough Counties are being mined out,
and all mining will eventually move southward.
The phosphate industry stated in 1965, "that it will reclaim
about 80 percent of the land mined in the future."' This
reclaimed land could then be made available for residential,
industrial, or agricultural uses. The phosphate industry
controlled about 520 square miles in 1967; about 80,000 acres
or 125 square miles had been mined and about 10,000 acres had
been reclaimed through 1965, mostly in Polk County. However,
65 percent of land mined in 1961-70 has been reclaimed.
There is very little public land in the study area. The federal
government owns the mineral rights to some acreage. There is
about 1,200 square miles of private land in the area; the most
significant acreages are large tracts of land currently in citrus
groves and large cattle ranches. Some of these lands are underlain
by phosphate, and in all probability the land will be made
available to the phosphate industry sometime in the future for
The main recreational areas are those that have been donated
by the phosphate industry for public use. These lands have either
been deeded outright to the county or State or leased for long
EFFECT OF LAND USE CONFLICTS
CONFLICTS WITH OTHER USERS FOR LAND RESOURCES
What are the effects of land use conflicts? First, let's identify
conflicts with other users of the land resources the water.
The four large users of water in the area are the phosphate
industry, citrus industry, food packing companies, and
municipalities. Under normal conditions, water is in abundant
supply; however under drought conditions, there may be
competition for the water supply. Projected water needs in the
southwest Florida Basin are adequate through the year 2015.
However, it is anticipated that soon after 1980, some of the
more industrialized subbasins which have expanding urban
populations will have water shortages. Water will then have to be
GEOLOGY OF INDUSTRIAL MINERALS
diverted from subbasins with an abundant water supply to the
areas in need.2
CONFLICTS WITH OTHER USERS FOR LAND SURFACE
Secondly, let's identify conflicts with other users of the land
surface agriculture, urban, and suburban lands.
There is a conflict in the area for the land surface, and it has
become more acute in recent years. The phosphate industry
started mining in Florida in the late 1880's; many small
companies were formed and land acquisition of the known
high-grade deposits was active. By the 1930's much of the
reserve lands that are owned today had been acquired by the
The phosphate industry's growth contributed to the
expansion of cities and towns in the area, but much of the land
adjacent to the cities is owned by the phosphate industry. The
rapid urbanization of the study area within the past decade has
made the use of land for mining and water conservation a matter
of concern to the public as well as to industry. The influx of
population has created a need for land not only for housing and
industry, but also to replace land removed from agricultural and
recreational used by urbanization and mining activities.
Phosphate mining operations have had in the past and could,
in the future, have adverse and limiting effects upon agricultural
production in the study area. Croplands are reduced through
phosphate industry expansion. However, the land may still be
used for agricultural purposes both before mining and after
mining; but during mining and reclamation agricultural
productivity on these lands is reduced.
Phosphate property will not be available for development for
other uses until after mining and reclamation. Until recently,
mining usually rendered the land unsuitable for many other uses;
but since 1961, the phosphate mining companies have been
operating under a voluntary policy to reclaim the mined-out land
to "help meet the aesthetic and practical needs of the
community," as stated by the industry's Florida Phosphate
REGULATIONS AND CONTROLS ON LAND USE
Thirdly, let's look at the laws and controls that affect the
mineral industry. These include various zoning ordinances,
requirements, and public opinion.
Hillsborough, Manatee, and Sarasota Counties have zoning
ordinances regulating mining. Mining is permitted in
Hillsborough County in the agricultural zones; however a permit
is required to build a phosphate washer, chemical plant, or other
structure exceeding building requirements in these zoned areas.
Manatee County adopted an amendment to its zoning ordinance
in 1966 to regulate all mining operations in the county. This
amendment constitutes a complete program for mining,
including posting of bonds for reclamation of mined lands.
Sarasota County adopted a resolution in 1965 to regulate the
mining of phosphate and other minerals in the county. The cities
of Lakeland, Mulberry, Fort Meade, and Plant City do not
permit mining within their respective limits. Mining would only
be allowed by passage of a special ordinance.
Adverse public opinion has caused one phosphate company to
relocate a proposed new chemical plant and another to abandon
plans for mining under a lake.
The Southwest Florida Water Management District requires all
phosphate mining companies to submit a mining plan whenever
mining would affect drainage in the Southwest Florida Basin.
Florida Board of Conservation, Division of Water Resources.
Florida Land and Water Resources, Southwest Florida. 181 p.
REGULATIONS CONCERNING UTILIZATION
Lastly, let's look at some of the regulations which may restrict
the utilization of the phosphate resources. There are taxes,
reclamation requirements, waste disposal requirements, and
pollution control requirements; many requirements of this
nature are, of course, necessary to maintain environmental
Agricultural lands purchased by the phosphate companies are
taxed on the potential worth of the land rather than on the
lower agricultural assessment, though the lands are used for
agricultural purposes until mined.
Several severance tax bills have recently been proposed to levy
tax on all solid minerals in Florida.
Legislation on the State level has been proposed that would
require the industry to reclaim mined lands. Several of the
proposed severance tax bills allow credit for reclamation. In
1970, Polk County passed an ordinance requiring the phosphate
industry to reclaim all surface areas mined or disturbed.
Manatee and Sarasota Counties have ordinances requiring
phosphate companies to reclaim mineral land. The City of
Bartow has a resolution in its code stating if and when
permission is granted for mining within the city, restoration of
the land must meet certain requirements and be completed
before a specified date.
Air and water pollution in the phosphate industry is regulated
and enforced by the Florida Department of Air and Water
Pollution Control. The Department has set minimum
requirements for the construction of earthen dams at phosphate
mining operations to try to eliminate or reduce dam failures.
Construction of new plants is regulated by a permit system
which allows only a given number of plants to put effluents into
the air in a given area, thus attempting to keep pollution to a
minimum. Hillsborough, Manatee, and Sarasota Counties have
codes on air and water pollution control.
EFFECT OF LAND CONFLICTS ON MINERAL RESOURCES
There have been two instances in the study area where lands
with phosphate values have been lost to the phosphate
companies. One company lost approximately 36 acres that were
taken for use in the Interstate Highway System; although the
company was compensated, the contained mineral comprising
275,000 tons of phosphate rock was lost. Another phosphate
company lost 38 acres of phosphate reserves land due to
relocation and four-laning of a state highway; the company was
compensated for the surface but the contained mineral was lost.
Phosphate occurrences are found under many lakes in the
study area. Attempts have been made to obtain legal permission
to mine these lakes; but permission has thus far been denied.
Phosphate probably occurs under most of the cities in the
area. These lands are being put to their most valuable use;
therefore, most of the mineral deposits under them will be lost.
However, in several instances lands within the city limits of
Bartow have been mined and reclaimed. These lands were in
swampy areas, and unsuitable for other purposes in their original
form. After mining and reclamation, the lands were made
available for other uses.
It has been projected that there will be a water shortage after
1980 in some of the more industrialized basins. A water shortage
in the study area could hamper future phosphate production.
Mineral values would not be lost, but a serious conflict could
arise with other users of water affecting mineral production.
SWEENEY: LAND USE CONFLICTS
METHODS OF RESOLVING LAND USE CONFLICTS
PAST AND CURRENT TRENDS
Probably the major effort of the phosphate industry to
alleviate land use conflicts was to eliminate former practices that
did not consider the public interest. The primary effort has been
land reclamation activities and the installation of pollution
abatement equipment. The industry undertook its land
reclamation program to present a better public image, gain
public acceptance, and in some cases to realize a profit. While
the economics of reclaiming mined-out phosphate land in remote
areas are still none too promising, it is now considered good
business and good public relations to restore mined-out land.
Many land use conflicts exist, but the current situation in the
area should not be considered too serious as far as loss of mineral
resources are concerned; most of the conflicts can be resolved.
Mining has the least flexible land requirements of any of the
major users of land. Agricultural, community, and industrial
development can be accommodated in many areas, but mining is
naturally limited to the specific area in which the resource is
Clear and reasonable zoning laws concerning mineral resources
should be worked out with county governments to most
efficiently use available resources to the benefit of the
community and the industry. Close cooperation between
industry and government, and public awareness of mineral
resource problems and potential conflicts are necessary. Mineral
resources must be wisely conserved, and the mineral policies we
pursue must be farsighted, planned with thought, and based on
SEDIMENTARY FRACTIONATION AND INDUSTRIAL-MINERAL DEPOSITS
Robert L. Bates
The natural separation of one element or compound from others in the earth's crust is a rare geological phenomenon;
accumulation of large quantities of a separated substance forms mineral deposits of value. Although igneous and metamorphic
processes are effective at times, by far the most significant fractionation is sedimentary. High-silica sandstone, high-purity
limestone and dolomite, salt, and anhydrite-gypsum occur in very large deposits and are termed first-order fractionates. The
marine diatomite of California, the trona of Wyoming, and the kaolin of Georgia and South Carolina are in deposits of
comparable purity but smaller size, and are designated second-order fractionates. The paper considers the various processes
and environments in which such industrially valuable deposits were formed.
The earth's crust is a heterogeneous mixture, in which roughly
100 chemical elements are combined in manifold ways into
about 2,000 minerals, and the minerals in turn form a complex
array of rocks. In this mixture of substances, only rarely do we
find large deposits of any single material to the virtual exclusion
of all others. It is the purpose of this paper to examine those
deposits that, with little or no beneficiation, are pure enough
and big enough to be of value for large-scale chemical, ceramic,
refractory, or other special uses; and to review the processes by
which such deposits formed.
The requirements of purity and size rule out deposits of the
naturally occurring elements, whether metallic or nonmetallic.
Such sought-after substances as native gold, native copper,
diamond, graphite, and sulfur occur in minuscule amounts and
with abundant gangue from which they must be separated. The
same is true, furthermore, of metallic ores generally.
Porphyry-copper deposits are commonly considered to be very
large, but they drop out of consideration when we recall that
over 99 percent of such deposits is waste rock. The piles of waste
in lead-zinc districts, and the tailings ponds at gold mines,
remind us of the fractionation that man must do because nature
didn't. Igneous and metamorphic processes produce ore deposits
- small complex pockets of mixed-up rock from which a metal
may be profitably won but only sedimentary processes can
form deposits of earth material so pure that they can be used
essentially as is, and of a size measurable in billions of tons.
Four varieties of sedimentary rock, which occur in deposits of
exceptional purity and great size, are here termed first-order
fractionates. These are high-silica sandstone, high-purity
limestone (and dolomite), salt, and anhydrite-gypsum. Materials
of comparable purity but in smaller deposits, the second-order
fractionates, include California diatomite, Wyoming trona, and
kaolin of Georgia and South Carolina. All these deposits are at
least 90 percent pure; a grade of 95 to 97 percent is not
uncommon for most of those named. This purity requirement
rules out such large concentrations as the potash deposits of
Saskatchewan and the phosphate rock of Florida, in which the
concentration of desired mineral material falls far below 90
The St. Peter Sandstone of the east-central United States
averages 97 percent rounded and frosted quartz grains, the chief
impurity being clay. White clean sandstones of this general
nature are not uncommon in the geologic column, but the St.
Peter averages 75 feet in thickness over an area of about 225,000
square miles. This is hardly the common or garden variety of
sandstone deposit. In this single formation there are some 2,500
cubic miles of rock, nearly all of which is quartz. The St. Peter is
a source of high-silica sand in northern Illinois, in the St. Louis
area, and (under the alias of a correlative formation) in the
Wichita Mountains of Oklahoma. How did such a sedimentary
The St. Peter is the record of a Middle Ordovician sea that
slowly transgressed northwestward onto a continental platform
of low relief, carrying its white sandy beach with it (Dapples,
1955). As the platform subsided very gradually and the sea
advanced, 'quartz-rich sediment' was supplied from the Canadian
Shield by streams. No doubt the source of this sediment was one
or more older sandstones, themselves perhaps second-generation
rocks. Thus the St. Peter Sandstone consists of material that has
been washed and winnowed repeatedly in the channels of
ancient rivers and on long-vanished beaches.
The dimensions of the St. Peter as it exists today make it
comparable to a sheet of bond paper 13 feet by 13 feet. Thus it
is actually little more than a film. Gradual sinking of the
continental platform continued into post-St. Peter time, and the
film of sand was covered with limestones and shales.
Sands that accumulate in eugeosynclines are commonly
diluted with mud or other nonsiliceous matter, but in
miogeosynclines transgressive shoreline conditions may persist
long enough for an appreciable amount of clean quartz sand to
accumulate. The Oriskany Sandstone (Lower Devonian) and the
Tuscarora quartzitic sandstone (Lower Silurian) are well-known
Appalachian examples. The Oriskany locally rivals the St. Peter;
the Tuscarora, as much as 400 feet thick, is 97 to 98 percent
quartz over hundreds of square miles. The Eureka Quartzite
(Middle Ordovician) of California is a Cordilleran example. It
contains a member 250 feet thick that is reported to be more
than 99 percent quartz. All these rocks have been or are being
quarried for glass sand or other high-silica raw material.
GEOLOGY OF INDUSTRIAL MINERALS
Thus the seemingly formless, unfocused work of waves in the
shore zone can in time refine certain resistant earth materials to
a high degree of purity. The amount of material that can be
involved is suggested by the immense stretches of quartz sand
along the Atlantic Coast from New Jersey to Florida. It is easy
to believe that silicon and oxygen are the most abundant
elements in the earth's crust when we consider the essentially
pure silica that has been isolated and preserved in times past and
continues to accumulate today.
HIGH-PURITY CARBONATE ROCKS
Among the purest materials to accumulate in large quantities
are those limestones and dolomites from which all but 2 or 3
percent of foreign matter (generally clay) has been excluded. A
few limestones that accumulated under geosynclinal conditions
meet this requirement; notable examples are two Middle
Ordovician limestones of the Appalachians, the Valentine and
the New Market. The upper 70 feet of the Valentine limestone
('Bellefonte ledge') of central Pennsylvania is 70 feet thick and
averages 97 to 98 percent calcium carbonate. The New Market
limestone, in the Shenandoah Valley of Virginia, is 40 to 250
feet thick and is at least as pure. Both these formations are
quarried on a large scale.
As with sandstone, however, we find that the most extensive
deposits of high-purity carbonates form on the continental
platform. Two Middle Devonian limestones of northeastern
Michigan, the Dundee and the overlying Rogers City, total about
200 feet in thickness and produce a greater tonnage of
high-calcium limestone than any other formation in the country.
The upper 40 feet of the Columbus Limestone of Ohio (Middle
Devonian) is of high- calcium quality from the central part of the
state to Lake Erie, and for some 50 miles from the outcrop
down the regional dip toward the east. This part of the
formation totals about 40 cubic miles of rock. Several quarries
and one mine are active.
Middle Silurian dolomites that extend from northwestern
Ohio to northern Illinois are sheet deposits of high purity, much
utilized for fluxstone and as raw material for refractories. The
Racine Dolomite, a representative of these strata in Illinois, is
characterized by the presence of reefs, which range from a few
feet in width and height to at least a mile in diameter and 150
feet in thickness. Typically, reef cores and flanking strata are
high-purity stone; an analysis of reef rock from the famous
Thornton quarry south of Chicago shows 98.87 percent
carbonates. Interreef strata carry as much as 30 percent of clay
and silt and are not utilized.
Invertebrate animals and certain marine algae were the humble
agents that extracted pure calcium carbonate from the shallow
clear warm waters in which the creatures lived. From time to
time, waves ground up the shelly material, and currents spread it
over the sea floor. Great distance from land, or very low relief of
land, was an important part of the picture. The general aspects
of the environment of deposition can be seen on the Bahama
Banks of today. At those times when appreciable noncarbonate
sediments did enter the sea, only the reefs and their flanking
strata, standing above the general sea floor, were the sites of
deposition of pure carbonate. Wholesale dolomitization of
marine fossiliferous limestones of the Middle Silurian may have
taken place during early diagenesis, or much later, perhaps when
the rocks were blanketed by Upper Silurian evaporites that have
since been eroded away.
In sheer size of deposits, rock salt exceeds the other first-order
fractionates. There are at least 3,000 cubic miles of salt in the
Upper Silurian rocks of the New York, Ohio, and Michigan
basin, 10,000 cubic miles in the Upper Permian rocks of West
Texas-New Mexico, and probably far more than that in the
Louann Basin of the Gulf Coast. Other major North American
deposits are in the Pennsylvanian of the Paradox Basin of Utah
and in the Devonian of Saskatchewan. Large parts of these
enormous salt bodies contain only 2 to 3 percent of impurities,
chiefly anhydrite and clay.
Whereas the natural habitat of pure sandstone and limestone is
the broad continental platform, salt deposits are more
characteristic of the basins on that platform-basins that were
shallow at any given time but subsided concurrently with
deposition, so as to allow accumulation of several hundred to
several thousand feet of salt and associated sediments. As a result
of this depositional habitat, salt deposits tend to have the shape
of a lens, or mega-lens, rather than a sheet or film.
Once deposited, sandstone and limestone can be counted on
to stay put. Not so with salt, which is highly mobile in the
earth's crust. Salt movement has had profound influence on the
architecture of major crustal units as diverse as the Appalachian
Basin and the Texas-Louisiana continental slope. Salt movement
has helped localize immense stores of oil and gas, and current
theory holds that brines derived from salt basins were
instrumental in forming many ore deposits of the Mississippi
It has long been the conventional view that the dominant
process in the formation of salt deposits is evaporation, the
sedimentary basin acting as an immense salt pan, under a sun so
torrid that for long periods the loss of water to the atmosphere
exceeded inflow by streams. This concept is variously modified
to account for replenishment by increments of normal sea water
and escape of residual brines after removal of salt. Orthodox
views have been challenged, however, by Sloss (1969) and
Schmalz (1969), who suggest that much salt may have been
deposited from deep water, in density-layered brines occupying
basins that did not dry up and were not salt pans at all. It is clear
that the origin of major salt deposits continues to present
problems, as it has done since the time of Ochsenius nearly 100
years ago. Until strong counterevidence comes along, salt will
probably continue to be referred to as an evaporite.
Rock salt produced in the solid form and also as artificial
brine is one earth substance of which there is an essentially
limitless supply. Our affluence in this commodity is definitely
not in jeopardy.
Most of the salt-bearing basins contain a second product of
chemical precipitation, anhydrite. This rock has been hydrated
to gypsum in the near-surface parts of sedimentary basins.
Ancient seas left behind considerably less calcium sulfate than
sodium chloride, but still there are large amounts of the former
in some parts of the geologic section. Conservative figures
indicate, for example, more than 2,000 cubic miles of
anhydrite-gypsum in the Permian Basin. Though there is a
disproportionately smaller amount in the Silurian basin of New
York, Ohio, and Michigan, adequate supplies of gypsum exist
along the outcrop belt to support large mines and quarries.
Equivalent anhydrite beds in the subsurface are generally
Gypsum deposits show considerable variation in purity, and it
may be assumed that anhydrite deposits do also. The better
gypsum deposits, such as those of the Salina Formation of New
York and the Blaine of Kansas, contain no more than 4 to 5
percent of impurities, chiefly shale and dolomitic limestone.
Viewed in the large, anhydrite-gypsum deposits take the
lenticular form, like salt. The calcium sulfate is believed to have
formed as an evaporite, anhydrite being the parent material and
gypsum the result of hydration in the zone of weathering. Thus
BATES: SEDIMENTARY FRACTIONATION
gypsum deposits are shallow deposits, and an operator cannot
expect to carry his mine indefinitely down the dip or beneath
Gypsum is widely utilized in the manufacture of plaster and
wallboard, but anhydrite is little used, at least in this country. It
is a potentially limitless source of sulfur. As this is written,
however, the last thing that industry needs is a new and limitless
supply of sulfur. Consequently we consider the larger, anhydritic
part of this fractionate to be a mineral resource only in the
The three second-order fractionates to be discussed here -
diatomite, trona, and kaolin have in common a purity of 90
percent or greater, a size of deposit smaller than those previously
discussed, a lenticular form of deposit, and rarity or even
uniqueness of occurrence. In other geologic respects the
members of the group have little resemblance to each other.
One of the country's major concentrations of nonclastic silica
is in the Monterey Formation (Miocene) and the overlying
Sisquoc Formation (Miocene-Pliocene) of the Coast Ranges of
California. The silica is in the form of bedded chert, hard opaline
cherty shale, diatomaceous claystone, volcanic ash, and
diatomite. At Lompoc, on the north flank of the Santa Ynez
Mountains, there occurs about 1,000 feet of exceptionally pure
porous friable light-colored diatomite, much of which
approaches 100 percent silica. This rock is made up of the
microscopic siliceous envelopes or tests of the minute floating
plants called diatoms. A single cubic inch of diatomite may
contain 40,000,000 tests. The tests are of many shapes and
forms, most of which are angular, and are lavishly ornamented
with ridges, spines, holes, dimples, grillwork, and other
decorations down to the micron dimension. Angularity of grain
produces loose packing, which imparts good insulating
properties; siliceous composition means immunity to many
chemical reagents; and the nature of the grains imparts
tremendous surface area, which is utilized in diatomite filter
aids. The rock is selectively mined, and is processed into many
grades with a wide range of applications.
Unusual conditions must have existed in the arm of the sea
that occupied southern coastal California in the Miocene and
Pliocene. One was a negligible inflow of land-derived sediments.
A second was a continuing supply of nutrients phosphates and
nitrates in small amounts, and silica in large amounts for the
propagation of billions of billions of diatoms over a long period
of time. Phosphates and nitrates tend to move in a cycle,
returning to surface waters for re-use by the floating diatoms,
but silica, once incorporated into diatom tests, is taken out of
circulation. Thus an exceptionally large and continuous supply
of silica must have been available. Beds of volcanic ash are
prominent in the Monterey formation, and there seems to be
little doubt that volcanic activity was the source of the silica
utilized by the teeming diatom population and locked up in this
part of the geologic section. Bramlette (1946) believes that the
procelaneous and cherty shales of the Monterey Formation were
originally diatomaceous beds, which were altered to their present
form by solution and reprecipitation of silica.
There are many other deposits of diatomite in the western
states besides the one at Lompoc. All are of fresh-water rather
than marine origin, are smaller than the Lompoc deposit, and are
associated with volcanic rocks. A deposit at Clark, Nevada,
which supports mining operations, is very pure, hundreds of feet
thick, and is reported to contain several million tons.
Trona, or natural sodium carbonate
(Na2C03.NaHCO3.2H20), is mined by three companies in the
Green River Basin of southwestern Wyoming. The mineral occurs
in the Green River Formation (Eocene) as one of the sediments
deposited in Gosiute Lake, a most unusual, not to say unique,
body of water that was named by Bradley (1964). The trona, a
light amber translucent mineral, occurs both as crystals
disseminated in shale, and as discrete beds. Many other rock
types were laid down in the lake, among them laminated
marlstone, green clay shale, volcanic ash, and thin beds of oil
There are 25 beds of trona that are 3 feet or more in thickness
and at least 100 square miles in area. Two of these beds are being
mined. Altogether, some 75 billion tons are estimated to be
A grade of 90 percent trona is common, and 'within a single
mine substantial areas may contain minable beds averaging 93 to
94 percent trona and smaller areas may go as high as 97 percent'
(Mannion, 1969). The principal impurity is shale.
In some beds halite occurs with the trona, and Bradley
believes that the latter is an evaporite, deposited at a stage when
Gosiute Lake shrank and its waters became supersaturated under
an arid climate. If the St. Peter Sandstone is a sheet deposit par
excellence, the Green River trona is the very ultimate in
lenticularity. The salt-bearing section constitutes a lens within
the Wilkins Peak member of the Green River Formation; the
Wilkins Peak is a lens, and the Green River Formation itself is a
great lens sandwiched between the stream deposits of the red
Wasatch Formation below and the dark stream- and lake-
deposited beds of the Bridger Formation above.
Of the trona deposits Bradley (1948) has written, 'It seems to
me another illustration of the remarkable phenomenon of
geology wherein a rare combination of factors provides the
necessary environment for the formation of an unusual mineral
and then persists without significant change until huge quantities
of the rare product have formed... I confess that contemplation
of these laboratories of nature where a complex dynamic system
remains so long in apparent perfect balance fills me with
something very close to childlike wonder.' One can certainly
sympathize with this feeling. How did 75 billion tons of sodium
carbonate become concentrated only in this place and only at
this time? Mannion (1969) ascribes the concentration to surface
drainage from granitic rocks surrounding the lake basin. But
streams flowed across granitic rocks into other Rocky Mountain
basins during the Tertiary; why did trona accumulate in none of
those basins? Besides, we are attempting to account for a
geochemical anomaly of a very high order, which geologic
business-as-usual can hardly be expected to explain. It seems
more reasonable to relate the concentration of sodium carbonate
to volcanic processes. Increments of ash that repeatedly fell into
Gosiute Lake may have contributed sodium directly, and, as
these same ash falls must have blanketed the surrounding area,
streams would have added more sodium in solution. Bradley and
Eugster (1969) lists eight thermal springs in the inferred
hydrographic basin of the lake, several of which are rich in
alkalies. It thus seems likely that sodium could also have been
contributed from Eocene hot springs. The 'laboratory of nature'
that produced the trona was, then, like the one that provided the
silica for the Lompoc diatomite, in the last analysis presided over
KAOLIN OF GEORGIA AND SOUTH CAROLINA
Lenses of white kaolin as much as 40 feet thick and a mile
across are enclosed in coarse micaceous sands of the Tuscaloosa
GEOLOGY OF INDUSTRIAL MINERALS
Formation (Upper Cretaceous) in two districts on the coastal
plain of Georgia and South Carolina. Material mined runs at least
94 percent kaolin. Impurities are detrital quartz and mica.
How such masses of pure clay could become emplaced in the
midst of cross-bedded stream-laid sands poses a nice problem in
sedimentation. According to a hypothesis presented by Kesler
(1957), rapid erosion of granitic rocks of the adjacent Piedmont
Province produced unweathered sediments that were transported
directly to the ocean by streams. Growth of vegetation in the
source area prevented iron from becoming oxidized, and it was
carried to the sea in the ferrous state, bypassing the plastic
sediments. Detrital feldspar, quartz, and mica were built into a
series of coalescing delta deposits above sea level, and subjected
to prolonged weathering. Kaolinite, formed by decomposition of
feldspar grains disseminated through the delta sands, was washed
into cutoff stream segments containing fresh water. As kaolin
accumulated, sand was periodically washed into and over the
edges of the deposits. The kaolin-filled ponds were eventually
covered by sands and preserved, forming the lenticular deposits
that are mined today.
Buie (1964) points out that the kaolin deposits occur in a part
of the geologic column that contains much evidence of volcanic
activity in Texas, Arkansas, Mississippi, and Puerto Rico. He
suggests that volcanic ash from vents in the Mississippi
Embayment and Gulf Coast regions settled on land, was washed
into valleys and lagoons, and became altered first to
montmorillonite and later to kaolinite. Purity of the clay,
absence of fossils, and lack of bedding are reasonably accounted
for under this hypothesis. Thus it may turn out that these pure
kaolins join diatomite and trona in having a volcanic ancestry.
Potential contaminants of the St. Peter and other high-silica
sandstones were kept out of the deposits by bypassing if
finer-grained, by grinding up and washing away if weaker, or by
otherwise failing to survive the rigorous and long-continued wave
abrasion on ancient beaches. Distance from shore, or low relief
of land areas, kept terrigenous detritus from the high-purity
limestones and the Lompoc diatomite. The aridity that caused
precipitation of salt and gypsum in the shallow sea and trona in
Gosiute Lake inhibited stream flow and hence the delivery of
much plastic material to the sites of deposition. And sand-size
detritus was kept out of kaolin pockets on a deltaic complex
because streams either filtered clay-size material from the
surrounding sediments or washed in fine volcanic ash from
Diverse sedimentary processes, operating in widely varying
environments at different times and places, have had one
attribute in common: the capacity to produce large mineral
deposits of great purity.
Bradley, W. H., 1948, Limnology and the Eocene lakes of the
Rocky Mountain region: Geol. Soc. America Bull., v. 59,
-- 1964, Geology of Green River formation and associated
Eocene rocks in southwestern Wyoming and adjacent parts
of Colorado and Utah: U.S. GeoL Survey Prof. Paper
and H. P. Eugster, 1969, Geochemistry and
paleolimnology of the trona deposits and associated
authigenic minerals of the Green River Formation of
Wyoming: U.S. Geol. Survey Prof. Paper 496-B.
Bramlette, M.N., 1946, The Monterey formation of California
and the origin of its siliceous rocks: U.S. Geol. Survey
Prof. Paper 212.
Buie, B. F., 1964, Possibility of volcanic origin of the Cretaceous
sedimentary kaolin of South Carolina and Georgia
(abstract) in W. F. Bradley, ed., Proc. 12th Nat. Conf on
Clays and Clay Mins.: New York, Macmillan, p. 195.
Dapples, E. C., 1955, General lithofacies relationship of St. Peter
sandstone and Simpson group: Am. Assoc. Petroleum
Geologists Bull., v. 39, p. 444-467.
Kesler, T. L., 1957, Environment and origin of the Cretaceous
kaolin deposits of Georgia and South Carolina: Georgia
Mineral Newsletter, v. 10, no. 1, p. 1-8.
Mannion, L.E., 1969, The trona deposits of southwest Wyoming:
Intermountain Assoc. Geologists, 16th Ann. Field Conf.
Guidebook, p. 195-204.
Schmalz, R.F., 1969, Deep-water evaporite deposition: a genetic
model: Am. Assoc. Petroleum Geologists Bull., v. 53, p.
Sloss, L.L., 1969, Evaporite deposition from layered solutions:
Am. Assoc. Petroleum Geologists Bull., v. 53, p. 776-789.
ECONOMIC GEOLOGY OF FLORIDA HEAVY MINERAL DEPOSITS
T.E. Garnar, Jr.
E.I. du Pont de Nemours & Co.
Heavy mineral mining has been a small,- but important Florida industry over the past sixty years. Early geologic history of
each deposit is similar up to point of deposition in alluvium, deltaic sediments, or along shorelines. Later geological
development through reworking and concentration is different for each deposit. The Trail Ridge deposit was formed by
reworking Citronelle sediments of the Lake Wales ridge. Post depositional leaching of iron from ilmenite makes Trail Ridge an
important source of titanium minerals for TiO2 pigment manufacture.
Research leading to the separation and sale of by-product heavy minerals from Florida deposits has been important in
maximizing profitability. Advances in mineral dressing technology will lead to future mining of lower grade reserves. Future
needs for heavy minerals seem certain to expand, with increased activity in exploration and development of mining operations.
Heavy minerals have always been important to Florida.
Although heavy mineral mining is small compared to phosphate
and other minerals mined in Florida, its continuing importance
to the state makes it appropriate that a program on industrial
minerals should have this industry represented.
The first beach sand mining operation was located at "Mineral
City" on the coast just south of Jacksonville Beach. During
World War I, rutile was mined for use in producing titanium
tetrachloride for tracer bullets. Following the war, this operation
became inactive and the site is now the Ponte Vedra Country
Club. There was only a small amount of activity and interest in
heavy minerals in the intervening years until World War II. The
Humphreys Mining Company operated a heavy minerals mine
just east of Arlington near Jacksonville from 1944 through 1964.
Hobart Brothers operated a mine near Vero Beach to produce
rutile for their welding rods during the 1946-1963 period. Both
of these are inactive at the present time. The Jacksonville deposit
was mined out and Humphreys moved their equipment to
Folkston, Georgia to mine a deposit belonging to the E.I. du
Pont de Nemours Company. Hobart phased out their operation
after securing other rutile sources. A deposit at the south end of
Amelia Island owned by Union Carbide was scheduled for
mining in the late 1950's. Plans to mine it were abandoned and
the property was sold in 1970 for development as a recreational
The only heavy mineral mines now operating in Florida are
the Du Pont mines at Starke and Lawtey; however, another mine
is under development just south of Green Cove Springs near
Penny Farms. This will be operated by Titanium Enterprises, a
joint venture between the Union Camp Corporation and
American Cyanamid Company. All of these deposits are
operated primarily for titanium minerals.
The purpose of this paper is to bring together the geology,
mineralogy, and economic uses for Florida heavy minerals, and
relate them to present and future exploration, mining, and
The geology of a heavy mineral deposit is complex and has its'
beginning eons before final deposition and many miles from the
deposit. None of the valuable minerals associated with heavy
mineral deposits are known to occur as primary minerals in
Florida rocks. The presence of crystalline rocks in an area called
the Hinterland by J.L. Gillson (1959), is the most necessary
prerequisite to formation of a heavy mineral beach sand deposit.
Peneplanation and formation of soil zones during which time
magnetite is decomposed and leached out by ground waters is
the second required step. Uplift and erosion of the soil zone is
the third, followed by transportation and deposition in alluvium,
deltaic sediments, or along shorelines. To this point, all of the
heavy mineral deposits have similar history. From this point on,
however, each deposit has its own individual geologic history,
equally complex and each different from the other. I will discuss
a typical case using the Trail Ridge deposit as an example.
Early workers, like Spencer (1948), believed the source of
Trail Ridge heavy minerals was Marion, Lake, Polk, and Highland
counties. Erosion of barrier islands, bars, and spits there released
heavy minerals which were washed northward to be
reconcentrated along Pleistocene shorelines. Important
contributions were made to the geology of the deposit by Bishop
(1956), and Brooks (1966). The most recent contribution has
come from Pirkle and Yoho (1970). They point out that the
Trail Ridge along which the heavy minerals occur is younger
than the Lake Wales Ridge extending down the center of the
state to Lake Wales. The Lake Wales Ridge is composed of coarse
Citronelle sediments containing almost identical mineral
assemblage to that of the Trail Ridge ore body. These are
distinctive through the absence of epidote, garnet, and monazite
which are common in heavy minerals throughout the rest of
The Trail Ridge sands were localized by currents impinging on
the northern end of the Lake Wales remnant. These sands
wrapped around the remnant. Much of the sand deposited along
the eastern side of the remnant was later removed through
erosion. Along the western side of the Lake Wales remnant, Trail
Ridge sands were built into beach ridges. Some of the sands were
blown inland to form a blanket over Citronelle sediments. The
part of Trail Ridge that is banked up behind, and that
encroaches on, the Lake Wales remnant is the part that contains
the heavy mineral ore body. Dune and wind-blown sands are
important parts of Trail Ridge. The important part of Pirkle and
Yoho's theory is that the presence of the Lake Wales remnant
was critical to the formation and concentration of the heavy
The Trail Ridge deposit is approximately 18 miles long and
averages about one mile in width and ranges between 25 and 70
feet in depth. The heavy minerals are disseminated in
cross-bedded sands. Organic material (humate) made up of
carbonized plant residues and kaolinite occur throughout the
deposit. In localized areas, the humate is present in sufficient
concentrations to cement the sand grains into a poorly
consolidated sandstone. The cemented sandstone areas are
lenticular and occur randomly with no apparent correlation as to
depth. These features probably represent sites of ancient swamps
present during development of the deposit.
GEOLOGY OF INDUSTRIAL MINERALS
Heavy mineral composition is the most important
consideration in evaluating economics of a potential ore.
Ilmenite with 65% or less TiO2 is used by pigments
manufacturers with the sulfuric acid process. The higher the
TiO2 content, the more value it has to them., The high TiO2
leucoxenes and rutile are insoluble in sulfuric acid and therefore
cannot be used in that process. They are used in the production
of titanium tetrachloride which in turn is used in the
manufacture of pigment and titanium metal.
Ilmenite by definition is a mineral with composition
FeO'TiO2. This mineral is rarely found in nature in its
theoretical form. The rock ilmenites occur in close association
with magnetite and hematite. Excess Fe2zO can enter the
ilmenite lattice; however, this exsolves and is removed by
leaching. This takes place in Area "A" of the triangular diagram
shown in figure 1.
Ilmenite is liberated by rock weathering and with other
minerals transported by water and deposited. As shown in the
Area "B" to "C" of the triangular diagram, the ilmenite oxidizes
and Fe203 forms at the expense of FeO. The structure is
destroyed leaving a mixture of amorphous Fe and Ti oxides. This
is shown by the Trail Ridge ilmenite x-ray pattern in figure 2. As
oxidation to Fe203 progresses down the "boomerang", leaching
is accelerated and the insoluble particles become enriched in
TiO2. The remaining TiO2 between "C" and "D" begins to
recrystallize in the form of secondary rutile as shown by the
Trail Ridge leucoxene x-ray pattern. We have separated particles
from the Trail Ridge titanium mineral fraction for each of the
points shown on the area "C" through "E". Details of this
alteration sequence is given by Temple (1960).
One of the most controversial aspects of the titanium ore
science is the accurate naming of the alteration products of
ilmenite minerals. Most workers in the titanium mineral field
recognize the inadequacy of the names ilmenite and leucoxene.
Many have proposed new names: Gillson (in Carpenter et. al.
1953) wanted to adopt the name "arizonite"; Lynd (1960)
wanted to call it ilmenite (qualified with an appropriate
adjective) and use the word leucoxene for alteration products.
Temple (1966) proposed the name "pseudorutile" for the
intermediate TiO2 minerals having composition Fe203'3TiO2.
Because present nomenclature is well established with
pigments-oriented geologists, I believe that future workers will
continue to call the black, opaque, para-magnetic grains
containing less than 65% TiO2 by the name "ilmenite"; the less
magnetic, lighter colored, alteration products from ilmenite
containing from 85% Ti2O to 98% TiO2 will continue to be
called "leucoxene". The primary unaltered rutile grains
associated with heavy minerals have always been called rutile -
even though some of these grains may be anatase or brookite.
A test has been devised for simplifying identification of these
products. Heating samples to 2000 F produces color changes as
Color Before Color After
%TiO2 Heating Heating
Ilmenite 65% Black
Altered Ilmenite 70-85% Brownish-Black
Leucoxene 85-98% Tan, Gray to Black
Primary Rutile 98%
As mentioned earlier, all heavy mineral deposits are operated
for the titanium minerals. In mining and processing, the
concentrators are normally set for best overall heavy mineral
recovery, so many of the heavy mineral silicates present in the
ore are recovered with the titanium minerals. In the interest of
economy and conservation of natural resources, uses and
markets should be sought for these non-TiO2 minerals. The
common heavy mineral silicates and their uses are discussed
A garnet is an isotropic, colorless to red, translucent mineral
which is strongly paramagnetic. It occurs in all known
southeastern heavy mineral deposits except Trail Ridge. It has
been separated and sold as an abrasive. None is produced from
Eastern beach sand deposits at the present time.
Staurolite is a red to brown, anisotropic, translucent mineral
which is strongly paramagnetic. It occurs in most of the
southeastern deposits. It is produced by magnetic separation of
the titanium mill high tension tailings at Starke. The mineral was
originally sold for its Fe2zO and A1203 content to the Florida
cement industries. Coarse staurolite (plus 48 mesh) is sold as an
abrasive. A special grade of staurolite is soon to be introduced as
specialty foundry sand and will be marketed under the trade
name "BIASILL". the name "BIASILL" is the acronym for
"basic iron-aluminum-silicate". Du Pont is the only source of
staurolite mineral of this type in the world.
Tourmaline is a dark green to black, pleochroic, translucent
mineral having about the same magnetic properties as staurolite.
No market has been developed which would warrant
development of a separation process for this mineral alone.
Epidote is a colorless to green, anistropic, translucent mineral
with practically the same magnetic properties as staurolite. It
occurs in most of the southeastern deposits except Trail Ridge.
No commercial applications are known for this mineral. Its
chemical composition is unsuitable for cement manufacture.
Low refractoriness and unfavorable expansion characteristics
would not make it a candidate for foundry or refractory use.
Monazite occurs as very fine (-150 mesh) almost spherical
grains. Color ranges from very pale yellow to green. Its magnetic
properties are similar to those of staurolite. It occurs in most
southeastern deposits, but is essentially absent in the Trail Ridge
deposit. High specific gravity and magnetic character are used in
separating this mineral. It was once valued for its thorium
content which was originally used in lamp.mantles and later in
nuclear applications. More recently, it has been in demand for
use in manufacturing color television phosphors. At the time of
this writing, monazite markets are reportedly declining.
Xenotime occurs as very fine grains similar in color and other
properties to monazite. Grains are frequently irregular shaped
and angular. It can be easily recognized by its extreme
birefringence and its relief which is very similar to calcite. It has
recently been in demand for its rare earth content. It occurs in
many of the southeastern deposits, but is absent in the Trail
GARNAR: ECONOMIC GEOLOGY
Zircon occurs as colorless to slightly pink (hyacynth), highly
birefringent elliptical grains. It is non-magnetic except in a few
rare grains containing inclusions of magnetic minerals (Fe304).
Its very high specific gravity and non-magnetic character allows
this mineral to be separated into very high grade concentrates.
Zircon was produced as a by-product from the Ponte Vedra mine
in the 1920's and the operators patented its use as a "refractory
sand". Only limited use was made of zircon until the late Forties"
when it began to gain wide acceptance in the steel industry as a
mold facing sand and later as a mold wash in flour form. Only
small amounts of the zircon produced goes into refractories,
zirconium chemicals, and metal. It is ubiquitous in southeastern
heavy mineral deposits. Du Pont is the only major producer of
high grade zircon in the United States at the present time.
The lighter (specific gravity 3.2 to 3.5) non-magnetic heavy
mineral fraction of most southeastern suites consist of kyanite,
sillimanite, and corundum with small amounts of topaz.
Spectrographic analysis of these minerals shows trace amounts of
beryllium, suggesting the presence of beryl in some deposits.
These minerals are being separated at Trail Ridge and marketed
by Du Pont under the trade name "KYASILL". Grain size,
shape, refractoriness, and excellent resin coating properties of
this product are superior to any other known specialty foundry
sand in certain applications.
At Starke, we are nearing our goal of utilizing all of the
recoverable heavy minerals and leaving only the silica sand
behind. This has been achieved through continuing research
efforts: First, to find economic processes to separate and
concentrate the various heavy mineral fractions; and second,
assiduous search for new uses and markets which can utilize
special properties of these non-TiO2 heavy minerals.
Advancing technology in mineral dressing will probably
change grade requirements for future deposits. An Australian
separator called the "Reichert" cone concentrator is a new
development in high tonnage processing. It consists of a series of
pinched sluices and cones which upgrade low grade ores to a
point where they can be finished in a conventional spiral plant.
Another high-tonnage-low investment device called a "Lamflow
Sluice" is being marketed by Carpco in Jacksonville. Use of this
type of equipment will allow .deposits which heretofore were
considered uneconomic for spiral processing to be worked, thus
assuring sufficient heavy mineral production to meet future
The need for heavy minerals in the future seems certain to
increase. It seems unlikely that a satisfactory white pigment
substitute for TiO2 will be found in the foreseeable future.
Considering that heavy mineral deposits furnish the highest TiO2
raw materials for pigment manufacture, then it seems reasonable
to assume that exploration for heavy mineral deposits will
continue and new mining operations will open at an increased
rate. Supporting evidence is the new mine which begins
operation at Green Cove Springs next year; the new ASARCO
ilmenite operation now in the planning stages for the Lakehurst,
New Jersey area; and the exploratory activity for heavy minerals
in the Tennessee area.
Bailey, S.W., Cameron, E.N., Spedden, H.R., and Weege, RJ.,
1956, The alteration of ilmenite in beachsands: Econ.
Geology, v. 51, p. 263-279.
Bishop, Ernest W., 1956, Geology and ground-water resources of
Highlands County, Florida: Florida Geological Survey,
Rept. of Invest., No. 15, 115 p.
Brooks, H.K., 1966, Geological history of the Suwannee River,
in Geology of the Miocene and Pliocene series in the north
Florida-south Georgia area, N.K. Olson, Ed.: Atlantic
Coastal Plain GeoL Assoc. 7th Field Trip, Southeastern
Geol. Soc. 12th Field Trip, Guidebook, p. 37-45.
Cannon, Harry B., 1950, Economic minerals in the beach sands
of the southeastern United States: Symposium on Mineral
Resources of the Southeastern United States, Snyder,
F.G., Ed., Univ. of Tenn. Press, p. 202-210.
Carpenter, J.H., Detweiler, J.C., Gillson, J.L., Weichel, E.C. and
Wood, J.P., 1953, Mining and concentration of ilmenite
and associated minerals at Trail Ridge, Fla.: Mining Eng.,
v. 5, p. 789-795.
Creitz, E.E. and McVay, T.N., 1948, A study of opaque minerals
in Trail Ridge, Florida dune sands: Am. Inst. Mining
Metall. Engineers, Tech. Pub. No. 2426, p. 1-7.
Gillson, J.L., 1959, Sand deposits of titanium minerals: Mining
Eng., v. 11, p. 421-429.
Grogan, R.M., Few, W.G., Garnar, T.E. and Hager, C.R., 1964,
Milling, at Du Pont's heavy mineral mines in Florida:
Milling Methods in the Americas, Nathaniel Arbiter, Ed.:
VII International Mineral Processing Congress, N.Y.,
Gordon and Breach Science Publishers, p. 205-229.
Lynd, L.E., Sigurdson, H., North, C.H. and Anderson W.W.,
1954, Characteristics of titaniferous concentrates: Mining
Eng., v. 6, p. 817-824.
Lynd, L.E., 1960, Alteration of ilmenite: Econ. Geology, v. 55,
Lynd, L.E., 1960, Study of the mechanism and rate of ilmenite
weathering: Am. Inst. Mining Metall. Engineers, Trans., v.
217, p. 311-318.
Palache, C., Berman, H. and Frondel, C., 1944, The system of
mineralogy of J.D. Dana and E.S. Dana: John Wiley and
Sons, 7th Ed., v. 1, 834 p.
Pirkle, E.C. and Yoho, W.H., 1970, The heavy mineral ore body
of Trail Ridge, Florida: Econ. Geology, v. 65, p. 17-30.
Spencer, R.V., 1948, Titanium minerals in Trail Ridge, Florida:
U.S. Bur. Mines, Rept. of Invest. No. 4208, 21 p.
Swanson, V.E. and Palacas, J.G., 1965, Humate in coastal sands
of northwest Florida: U.S. Geol. Survey Bull. No. 1214-B,
Temple, A.K., 1966, Alteration of ilmenite: Econ. Geology, v.
61, p. 695-714.
GEOLOGY OF INDUSTRIAL MINERALS
* does not show
*\any analyses in
, this area
Figure 1. Triangular diagram showing chemical relationship of various iron and titanium oxide minerals.
GARNAR: ECONOMIC GEOLOGY
.,,,,l .............. .......... l. ..i .n.i.. 4, IIl ,
F.u... .-r \.... ....rn ..... ..1 min
F 2.X- d.-- pftiTe -.o- Tr
Figure 2. X-ray diffraction patterns of Trail Ridge titanium minerals.
ORIGIN, DIAGENESIS AND STRUCTURE OF BAUXITE DEPOSITS IN
Glenn P. Jones
General Refractories Company
Stevens Pottery, Georgia
Laterization of syenite and other rocks in north Alabama produced material which was picked up and carried by streams to
southeast Alabama. These streams deposited the aluminum rich material in the sinkholes of a karst topography developed on
the Clayton Limestone. Measurement of the bearing of the long axis of each deposit in the Screamer area, along with plotting
the location of these deposits on a map, indicate a depositional pattern controlled by local fractures or solution zones in the
Clayton Limestone. The sinkholes and channels dictated the original structure of the deposits. Additional structure changes
have resulted since compaction of the deposits by continued solution of the underlying limestone. The original material in
these deposits was enriched by the removal of silica to form bauxite and bauxitic kaolin during deposition and compaction.
Subsequent ground water action has reintroduced silica into the deposit leaving a core of bauxite.
The bauxite producing area of Southeast Alabama is in Henry
and Barbour Counties and extends over approximately 180
square miles (figure 1). This area is in the Coastal Plain Province,
with the bauxite being found in the lower Eocene deposits of the
"Nanafalia Formation." Directly under the sand member of the
Nanafalia Formation is a porous limestone of the Midway group,
known as the "Clayton Formation" (MacNeil, 1945). The
contact between the Nanafalia and the Clayton Formation is an
The bauxite and surrounding deposits are easily recognizable
as sedimentary with the apparent bauxite source material being
found in North Alabama. The limestone underlying the bauxite
is responsible for the presence and structure of the deposits.
Changes within the deposits have taken place since deposition, as
evidenced by the halo of bauxitic clay and kaolin around a core
For exploration and mining purposes a deposit is generally
graded by the alumina or silica content. Figure 2 is a graph
showing the aluminum oxide on a raw and calcine basis, with the
corresponding percentage of loss on ignition. The third line
shows the same relationship between the silica content and loss
The ore is divided into three categories, depending on the
percent of aluminum oxide present. On a raw basis ore with
greater than 50% aluminum oxide is considered bauxite;
45%-50% is bauxitic kaolin; 40%-45% is kaolin. Material with less
than 40% aluminum oxide is clay and is generally not usable for
refractories because of the presence of illite, montmorillonite
and other clay minerals.
Residual clay deposits in the Piedmont Province of North
Alabama indicate this area was a source for the Southeast
Alabama bauxite deposits (Clark, 1963). This was the closest
source for the large mica flakes which are associated with the
bauxite deposits. Laterization of igneous and metamorphic rocks
in the Piedmont Province produced the residual clay deposits,
which were carried by streams crossing the area south to be
deposited in the Karst topography of Southeast Alabama.
The material originally deposited in the sinkholes was
probably very similar to the clay which is present in the lower
portion of the present deposits. This clay appears to have
undergone little or no diagenesis and contains primarily kaolin,
illite and silica.
The change from the original clay sediments to bauxite with
the intermediate stages of kaolin and bauxitic kaolin can best be
explained by the leaching of the silica.
Silica is soluble in pure water and is more soluble in slightly
alkaline waters (Harder, 1933). Percolating ground water passing
through the clay deposit would become slightly alkaline and
more readily remove the silica cation from the clay.
MacNeil (1945) has shown that marine deposits of the
Nanafalia Formation are present just to the south of the bauxite
district. This would indicate a low lying area in which
meandering, shifting streams were depositing clay minerals in the
quiet waters of the sinks, with the sands deposited at the
entrance to the sink. The sand at the entrance would cause the
stream to shift, leaving a pool or lake filled with clay sediments.
Once the stream had shifted, there would not be the continued
introduction of silica into the deposit by stream water.
The lignite deposits associated with these bauxite deposits
indicate ample rainfall to provide water for leaching the silica.
Lignite deposits may be found in any position around the
deposit. Infrequently, lignite may be found on top of the
The lignite below the bauxite deposits formed before
deposition of the clay sediments and during the development of
the Karst topography. When the limestone collapsed, a more
rapid drainage occurred in the sinkhole which was full of clay
sediments. This drainage prevented the growth of vegetation and
the formation of lignite deposits by draining the moisture away
from the surface.
As the kaolin became more indurated, drainage through the
deposit became slower, permitting the growth of enough
vegetation to form lignite on top of some deposits.
The leaching of silica by percolating water would begin near
the top of the deposit and progress gradually downward. After
the overlying Nanafalia and Tuschoma Formations were
deposited, silica was reintroduced into the bauxite by ground
water saturated with silica which the water had picked up from
the overlying sediments.
Both the leaching and reintroduction of silica have left a
gradational contact between the core of bauxite and surrounding
bauxitic kaolin and kaolin.
As could be expected, this gradational contact is irregular,
with the deepest penetration of the leaching or reintroduction of
silica occurring along the course followed by the water.
In a small road cut approximately 1000 feet north of Price's
Store on the Cotton Hill Road in Barbour County, Alabama,
(SW4, Sec. 22, TO1N, R27E), a deposit of kaolin and clay is
exposed. For the most part, the deposit is clay enclosing small
pockets of kaolin. The contacts between the clay and kaolin are
GEOLOGY OF INDUSTRIAL MINERALS
S--Bauxite Producing Area
p p I
Figure 1. Map of Alabama showing bauxite producing area.
JONES: STRUCTURE OF BAUXITE DEPOSITS
M 04 -4 o M 00 r %0 rn t cn o o\ co t- %o L T f> c4 1- q
Mn MC M Mc 4 Cv, Cq C4 04 C Co N Ji C r4 r4N -l N-4 r- 4 rl-4 r4N i
JONES: STRUCTURE OF BAUXITE DEPOSITS
GEOLOGY OF INDUSTRIAL MINERALS
02, /00 2.00
Figure 4. Map of bauxite deposits and bearings of long axes in Screamer, Alabama area.
GEOLOGY OF INDUSTRIAL MINERALS
Examination of a mining face in a bauxite pit will also show
gradational contacts between the bauxite, bauxitic kaolin and
kaolin. These changes in alumina content are almost always
accompanied by a change in texture of the ore.
Cores taken from deposits show clearly the change in texture
and related alumina content. The kaolin has a smooth texture,
while the bauxite frequently has an appearance like sugar
granules, especially when rubbed between the fingers. The
texture of bauxitic kaolin lies between the kaolin and bauxite.
Bauxite is frequently more difficult to recover in a core because
it is less cohesive than the kaolin and falls apart easily.
Drilling has shown the bauxite deposits are located in
limestone sinks. These sinks are shaped roughly like a cone with
the pointed end down.
Pinnacles of limestone often rise higher than the top of a
deposit. A map view of a deposit shows it to be irregular in shape
and generally longer than it is wide (figure 3).
Considerable ground water has passed through the deposits, as
evidenced by the slumping which has taken place in the ore
deposits as a result of solution and collapse of the underlying
limestone. Many deposits have what is called an "umbrella"
effect. This results from much of the ground water being
diverted over the edge of the deposit around the less permeable
clay. The additional water accelerated the solution of the
underlying limestone, permitting the edge of the deposit to
collapse forming a dome-like structure.
Not all sinks in the bauxite area contain clay sediments. It
appears the deposition of the clay sediments were controlled by
streams which crossed sinks in the Karst topography.
The location of the sinks may be a result of solution along
fracture zones in the limestone, with the formation of caves
which later collapsed.
It has been suggested that the long axes of the bauxite
deposits are oriented parallel to each other because of solution
along regional parallel fracture zones. Measurements of the
bearings on the major axes on thirty-three different deposits do
not indicate any pattern or alignment of the deposits over a wide
area (figure 3). However, there is some alignment between
deposits located in proximity, as shown in figure 3.
The existence of lateritic conditions prior to the deposition of
the bauxite deposits in Southeast Alabama is shown by the
presence of the residual clay deposits in North Alabama. These
conditions continued at least through early Eocene is indicated
by the presence of the bauxite deposits. All the necessary
conditions existed to produce the Southeast Alabama bauxite
deposits by laterization.
The orientations of the fracture and solution zones in the
limestone are of local extent and are not related to regional
structure patterns, which have a strike of N 500E.
The fact that local fracture and solution zones sometimes
created more than one sink in an area, which may have become
filled with clay sediments, should indicate to the geologist to
look thoroughly at the adjoining area once the first deposit has
Clark, O.M., Jr., 1963, Residual Clays of the Piedmont Province
in Alabama: Alabama GeoL Survey Cir. 20-A, 60 p.
Harder, E.C., 1933, Origin of bauxite deposits: Econ. Geol. v.
28, p. 395-398.
MacNeil, F.S., 1945, The Midway and Wilcox Stratigraphy of
Alabama and Mississippi: U.S. Geol. Sur. Strategic
Minerals Inv. Prelim. Map 3-195.
SAND AND GRAVEL EXPLORATION METHODS
The Standard Slag Company
Sand and gravel deposits may be explored by many different methods. The methods used by The Standard Slag Company
are primarily two in nature. One is using an auger which is limited in depth by various soil conditions. The other is a heavy
wall dry sampler and a heavy wall wet sampler. The heavy wall dry sampler takes continuous uncontaminated samples up to
seven inches in diameter. The heavy wall wet sampler takes continuous uncontaminated samples up to six inches in diameter.
For us, the maximum depth of the heavy wall samplers has been two hundred fifty feet of which one hundred feet was above
the water table and one hundred fifty feet was below the water table.
We use an auger type drill that is similar to the ones used by
electric power and telephone company pole-setting crews. Our
auger is a special model that is designed to drill to a total depth
of twenty-two feet. The auger bit size is eight inches in diameter,
two feet in length and the flights are approximately five inches
apart. We weld a hard surface to all parts of the auger bit that are
exposed to the abrasiveness of sand and gravel We have tried
twelve, eighteen, and twenty-four inch diameter auger bits but
found that the eight inch diameter auger bit is the best.
The auger type drill is mounted on a six by six truck with dual
tandem rear wheel assembly and single wheel front assembly that
can be converted to dual wheels when necessary. The truck is
also equipped with a front end winch for movement through soft
or steep terrain. The auger is mounted on a deck plate truck bed
so the derrick can be raised into a vertical position. We added a
depth indicator that registers the drilled depth to the nearest
half-foot. We use a two-man crew because of safety and
efficiency although the drill can be operated by one person. The
auger bit has power rotation both clockwise and
counter-clockwise. Downward pressure and upward pressure may
be applied to the auger bit.
After drilling through the overburden which is usually clay,
we advance the auger bit one foot into the sand and gravel by
rotating it clockwise. The auger bit is then pulled out of the
ground and the material on the flights of the auger bit is placed
in a coal or scuttle bucket. The bucket is emptied into a sample
box compartment. The sample boxes contain six compartments
each six inches deep, six inches wide and twelve inches long. We
use four of these boxes and the compartments are numbered one
to twenty-two. After the hole is completed, an equal amount
from each compartment is placed into a sample bag. We use an
iron coal shovel level full for our "equal amount" and a cloth
bag the same size as a ninety-four pound cement bag is used for a
sample bag. The sample bag is tagged both inside and outside
with a cloth tag that identifies the sample. (See figure 1).
We fill out a drillers log (See figure 2). Under the Description
we use the following terms: Very fine sand, fine sand, sand, sand
some gravel, sand and gravel (50% of each), gravel some sand,
gravel The size of the largest gravel is also recorded as well as
color, water content, dirty (as far as wash loss is concerned), clay
seams, coal or any other materials. All material under one-fourth
inch is considered sand.
We use a mortar hoe to immediately fill the completed test
hole. Believe it or not using a mortar hoe is a lot easier than any
type of shovel We overfill the hole by building a conical shaped
mound as high as possible directly over the hole. Usually these
holes must be refilled, especially if drilled in a permanent
pasture. Holes drilled in wooded areas have been found yetrs
after they have been drilled.
The soil conditions that often prevent us from drilling the
complete depth of twenty-two feet are as follows:
Figure 1. Cloth Tag.
1. Sand and gravel so clean or free of any binding material will
"cave in" or "fall in" so that we cannot drill the next foot
and pull our auger bit up through the cave-in.
2. Material such as hard shale, limestone, sandstone, and other
bedrock. We can drill beneath water but we can't obtain a
true sample of sand and gravel because the sand and gravel
won't adhere to the flights of the auger bit.
HEAVY WALL SAMPLER METHODS
We use a medium sized churn or percussion type drill with the
heavy wall samplers. We mount this drill on the same type truck
as described in the above auger type drill. More care is taken to
set up this machine because the string of tools must always be
centered over the pipe. We set the rear dual tandem wheels on
"setting planks" that are thirty inches wide, three inches thick
and six feet long. The back tandem wheels are "chucked" with
two four inch by four inch by eight foot long timbers in such a
GEOLOGY OF INDUSTRIAL MINERALS
manner that the drill cannot move forward or backward. Jacks
are placed under the rear frame of the drill, under the middle of
the truck frame, and under the front bumper. A wooden
platform about six feet by eight feet is built around the test
hole. Two men are required to operate this drill.
The pipe, heavy wall dry sampler, heavy wall wet sampler, and
the quadruple flap valve are illustrated in figure 3. The weld
between the coupling and pipe is to prevent the pipe from
"telescoping" into the coupling when the pipe is being driven
into the ground. The weld also keeps the coupling and pipe from
"pulling apart" when the pipe is pulled or driven from the
ground. The quadruple flap valve is only used when the material
is either wet or a very fine sand. When this valve is used in a
heavy wall wet sampler and the sampler is driven or forced down
into the material, the separate valves turn upward on their
hinges. From a side view the valve now looks like a crown of
four equal sized pieces of pie with "the first bite" up. The heavy
wall dry sampler is used when the material is dry to moist. We
start the test hole with the larger size heavy wall dry sampler, 7
7/8" O.D. and 7" I.D. and use the standard eight inch pipe.
When we encounter the water table, we change to the smaller
size heavy wall wet sampler, 5 7/8" O.D. and 5" I.D. and use the
standard six inch pipe.
In figure 4 we are illustrating the sampling steps used with
either one of the heavy wall dry samplers. The "string of tools"
is composed of a rope socket, drill stem, jars and heavy wall dry
sampler. The rope socket, drill stem, and top half of the jars
weigh approximately twelve hundred pounds and are actually
the drive hammer for the heavy wall dry sampler.
Between Step 1 and Step 2 the rope socket, drill stem, and
top half of jars have been put into a thirty inch up and down
motion thus driving the heavy wall dry sampler ahead of the pipe
for a distance of two feet. The up and down motion or stroke
occurs about fifty times per minute. Between Step 2 and Step 3
the string of tools have been pulled out of the pipe and placed
over the sample or "coal" bucket and the sample has dropped
into the "coal" bucket. Step 4 shows the pipe after it has been
driven down two feet. If, after driving the pipe, the sampler
won't "free fall" to its original depth in Step 2, we know there
has been a "cave in" of the last sample material which would
reduce the accuracy of the next sample. We again drive the
sampler to that depth, pull out the string of tools, and discard
this "cave in" material. Step 5 is a reproduction of Step 1, only
everything is two feet deeper. All of the material in the sample
bucket is emptied into a sample bas as described in the auger
method, and tagged inside and out. We put one two foot sample
of the larger 7 7/8" sampler into one sample bag but we put two
two=foot samples of the smaller 5 7/8" sampler into one sample
When sampling under water, we use exactly the same
procedure as shown in figure 4 except the pipe is driven four to
eight feet beyond the sample depth. Now the pipe has a four to
eight foot "plug" until two feet of "plug" remain. The pipe is
again driven four to eight feet beyond the sample depth. We
follow this method to keep sand and gravel from "heaving" up
the pipe. If we sample beyond the end of the pipe and pull out
the string of tools, occasionally the sand and gravel, especially
sand, will "heave" or fill the pipe up to the water table. If this
happens, then we must "clean out" the "heave" and discard all
the material. A driller's log as described in the auger method
section is filled out for each test hole.
After the test hole is finished, we pull the pipe out by using a
"slotted head" pipe puller or pipe pulling jars (See figure 5).
Either one of these reverses the pipe driving process by driving
up instead of down on the pipe. The hole is then filled in the
same manner as described in the auger method except excess
material is hauled to the test hole.
We have discovered that any material which can be sampled
by either of the above methods may be excavated without the
use of explosives. Time wise, we can complete one auger method
test hole to a depth of twenty-two feet every hour. With the
heavy wall samplers we can average approximately four feet an
The final figure 6 is taken from "Subsurface Exploration and
Sampling of Soils for Civil Engineering Purposes" -a report on a
research project of the American Society for Civil Engineers,
prepared by Hvorslev (1949, p. 26). Figure 6 shows in black
outline our methods as compared to other methods used in
subsurface sampling. As we must take samples to our laboratory
to be analyzed, the two methods, especially the heavy wall
sampling, has proved to be the most accurate. In one deposit of
several million tons, our estimated ratio of sand to gravel was
within one percent of the final tonnages produced.
Hvorslev, Mikael Juul, 1949, Subsurface exploration and
sampling of soils for civil engineering purposes: Vicksburg,
Miss., Waterways Experiment Station, 521 p.
McDONALD: SAND AND GRAVEL
Farm Date Hole No. Elev.
Location of Hole
Sample No. Depth.ft. Description
Figure 2. Drillers Log
GEOLOGY OF INDUSTRIAL MINERALS
L/Ne N .
kit erssc --
.CVUSLTNRD 8 26
-S/dog7ao 6 /9
8 V rWetK:AD~-- ____L
4-o47 7r1rL7 I
t'ARs, Of 5PtC/AL ,Ao
/EAVY" WALL T7U//A6
n q, 0 7'a/O'D.- 7I. .
- -o o
7-TV-r4 %6 V4/z
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AIEAVY' WALL D Y SA44PLE,
API pv ---
OcL .,7 ,4'?/ /vC L
,W 7 Rc0L. rj.^t //\
14 tY W/A I I- 1 \
E5l0A 7? ..0 & 7!7 A
jER6FOf4 AL4' LV'GE
/Vkr7e/ATrD /o40_a 0/4A(/PL0
57E. M//.E S0 FLAP VaLVE ACML/ .f_ P ^^S AI f; F-// ^
hle^r7.,-'o /040 A 4zzay // rE^ ie. 1040
V//--------Y0 ZeL o \ c. QL
MisY1 / 4LP LET 141/44Pz QW/E/^ ^/5 tLZAP VALVE
Figure 3. Pipe, heavy wall dry sampler, heavy wall wet sampler,
and a quadruple flap valve.
McDONALD: SAND AND GRAVEL 33
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-a: 'z3 9.a
cza l E
i 19 a)
1. i O O o oO o w R 0I ..
c, O ~a Z0)
D~ ~ 5
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a 1 P P~ 0
a. I9 a ,I
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GEOLOGY OF INDUSTRIAL MINERALS
PIPE PULLING JARS
Pipe pulling jars are used to pull strings of pipe
that have been driven into gravel or tight earth.
With tool joints on both ends, this tool is assembled
between the rope socket and drill stem.
The knocking head screws into the pipe coupling
and is tightened by inserting a rod in one of the holes
near the top. The weight of the drill stem below keeps
the jar straight in the knocking head, given a good
solid blow while jarring up. The drive clamps, when
placed on the upper wrench square of the jars, permits
jarring both ways.
SLOTTED PIPE PULLING HEAD
A slotted pipe pulling head for pulling short
strings of pipe either by a direct pull or jarring up.
Its collar is slotted so that it may be slipped over
the drilling cable and screwed into the pipe cou-
Figure 5. Pipe pulling jars and slotted pipe pulling head.
McDONALD: SAND AND GRAVEL
FULLER'S EARTH AND BENTONITE IN THE SOUTHEASTERN STATES'
Sam H. Patterson
U.S. Geological Survey
Fuller's earth and bentonite are two clay commodities that are interrelated either by mineral composition or use. Because of
this interrelation and the sale of both for many different uses, some ambiguity in their classification has resulted. The term
"fuller's earth" has no compositional or mineralogical meaning, and it is used more or less as a catchall for any clay or earthy
material suitable for certain uses. Most, but not all, of these uses require absorbent properties Bentonite by geologic definition
must have formed from volcanic ash or tuff or the glassy material in volcanic rock; most bentonites consist chiefly of
montmorillonite but other clay minerals may be present.) In industrial usage the term bentonitee" is applied to any clay
consisting chiefly of montmorillonite, irrespective of origin.
Georgia and Florida have historically been the leading States in the production of fuller's earth; bentonite has been
produced in Alabama on a small scale.The first major use of fuller's earth was in refining of oils)Other materials have replaced
fuller's earth for this purpose to a major extent, but many new uses for fuller's earth have been found, and production has
increased in recent years. The new uses include absorbent products, insecticide and pesticide carriers, drilling mud, and many
others) The bentonite now produced in Alabama is of the "southern," "low selling," or "calcium" type and is used mainly as
Most of the fuller's earth mined now is in the Hawthorn Formation of Miocene age; a lesser amount is produced from the
Twiggs Clay Member and other beds in the Barnwell Formation of Eocene age. Inactive pits from which fuller's earth was
produced from other formations occur at several localities. The bentonite now mined in Alabama is in beds of Cretaceous age;
several years ago bentonite was produced from Eocene beds in this State.
Extensive deposits of fuller's earth occur in the Southeastern
States, and this region has long been a major producer of this
commodity. Bentonite also occurs at several localities in the
region and is now produced on a minor scale in Alabama.
Some ambiguity exists in the classification and the reporting
of production and consumption of fuller's earth and bentonite
because the two commodities are interrelated. The difficulty
results from the indefinite definition of fuller's earth as
compared with the more precise geologic definition of bentonite,
and from the loose usage of the term bentonitee" by industry.
Some clay sold as fuller's earth actually is bentonite by geologic
definition, and not all clay classed as bentonite by industry
fulfills the geologic definition. Further complications in the
classification and reporting on these commodities come about
from the use of both for many different products and from the
sale of both for the same or very similar products, such as
The term "fuller's earth" has no compositional or
mineralogical meaning, and it is more or less a catchall for clay
or other fine-grained earthy material suitable for certain uses.
The origin, of the term dates back into antiquity; it was first
applied to material used in cleansing and fulling wool, thereby
removing the lanolin and dirt from it. When in the latter half of
the last century it was found that some earths used for fulling
would also serve in decolorizing and purifying mineral, vegetable,
and animal oils, the term "fuller's earth" was modified to
include this usage.
Extensive use of fuller's earth in processing mineral oils in the
first half of this century and the virtual end of its use in fulling
fiber led to the general application of the term "fuller's earth" as
meaning primarily earth used in petroleum processing. Further
modification of the meaning came about as other uses developed
for the earth. Now these other uses have replaced oil processing
as the major use, but the term "fuller's earth" is retained for a
wide variety of materials used for many purposes. Most of these
uses require absorbent properties in one form or another, and,
1 Publication authorized'by the Director, U.S. Geological Survey.
therefore, the valuable property is similar to the one originally
required for fulling wooL However, the properties required for
some uses, such as certain drilling muds and fillers, are other
than absorbency and, therefore, result in further abridgment of
The classification and understanding of fuller's earth is also
complicated by several terms with more or less duplicate or
overlapping meanings. When applied in the oil-processing sense,
fuller's earth has the same meaning as "naturally active clay."
Fuller's earth and other clay which are treated with acid to
improve their desirable properties are called "activated clay."
The term "bleaching clay" or "bleaching earth" is applied
mainly to naturally active and sctivated clay, but it also includes
activated bauxite (Rich, 1960, p. 93). Both naturally active and
activated clays are included under the term adsorbentt clays"
(Nutting, 1943) and, therefore, this term has nearly the same
meaning as bleaching clay. The term "absorbent clay" is applied
to fuller's earth used for a wide variety of purposes which are
different from that of processing oils.
Bentonite by most accepted geologic definitions must have
formed from volcanic ash or tuff or the glassy material in
volcanic rock; most bentonites consist chiefly of
montmorillonite, but other clay minerals and impurities may be
present. In industrial usuage, the term bentonite is applied to
any clay consisting chiefly of montmorillonite, irrespective of
Several people aided in the preparation of this article. Mr.
James D. Cooper of the U.S. Bureau of Mines, Atlanta, Georgia,
reviewed it while it was in the manuscript stage and made several
helpful suggestions. Messrs. S. M. Pickering, Jr., and James
Furlow of the Georgia Department of Mines, Mining and
Geology also read the manuscript and suggested improvements.
U.S. Geological Survey personnel who contributed to the report
GEOLOGY OF INDUSTRIAL MINERALS
include Mr. Robert W. Banks, who supervised the drafting of the
illustrations, and Miss Anne Sangree, who made editorial
HISTORY AND USES
Published reports give rather confusing accounts of the
discovery of fuller's earth in the United States. Several state that
fuller's earth was discovered in this country in 1893 near
Quincy, Florida, by the Owl Commercial Company (predecessor
of the present makers of White Owl cigars) during an attempt to
burn brick from clays on tobacco property. The clay was
unsuitable for making brick, but an Alsatian immigrant
employed as a farm worker recognized that it was similar to
fuller's earth mined in Germany. His observation led to
development of the first mine near Quincy 2 years later and to
the use of this clay in processing mineral oils. Fuller's earth had
been mined on a small scale, however, in Arkansas in 1891
(Miser, 1913, p. 208) and tested for use in the refining of
Both of these discoveries are related to the use of fuller's earth
in processing oils and fail to note its earlier use for other
purposes. Clays and other earthy materials were undoubtedly
used by the early settlers from Europe in cleansing wool and
other materials. The author made little effort to search the
historical records and document this, but he did find that
soldiers stationed near Perth Amboy, New Jersey, used
Woodbridge fire clay for cleansing buckskins during the
Revolutionary War (New Jersey Geological Survey, 1878, p. 1),
and fuller's earth associated with iron-ore bed near Kent,
Connecticut, had been mined prior to 1820 (Silliman, 1820, p.
217). Also, American Indians are reported to have used
bentonite in cleaning blankets, and they probably dug it for
other cleansing purposes before the Columbian period.
The use of fuller's earth in the refining of oils continued to be
the major one for many years. The demand for fuller's earth for
processing mineral oil increased rapidly in the first part of this
century and reached a peak of approximately 317,00 tons in
1930 (fig. 1); this was 97.1 percent of the total United States
production that year. The production of fuller's earth for this
purpose began to decrease thereafter, especially when activated
bauxite was introduced in 1937 and magnesium silicate in 1940
as more efficient substitutes. In recent years, the production of
fuller's earth for use in refining mineral oils has maintained a
rather uniform rate of 35,000 to 40,000 tons per year. The use
of fuller's earth in processing animal and vegetable oils has never
been a major one and has decreased to the point where it is
included as a part of the miscellaneous uses in the U.S. Bureau of
Mines Minerals Yearbooks.
Fuller's earth was first sold for drilling mud in 1941. The
market for this use expanded slowly and has maintained a level
of 8 to 10 percent of the total United States production during
the last few years. Most of the fuller's earth sold for drilling mud
comes from the southern part of the Meigs-Attapulgus-Quincy
district of Georgia and Florida (fig. 3). Attapulgite clays
produced in this area are superior to most other fuller's earth for
muds used in drilling salt formations, but they are inferior to
bentonite where the rocks drilled contain no salt water.
Fuller's earth was used in significant quantities as a carrier for
insecticides and fungicides by 1950, and the market for this use
has grown at a rather uniform rate since that year. In 1969,
nearly 20 percent of the fuller's earth produced was used for this
The use of fuller's earth granules for absorbent purposes began
during the 1930's, but this use did not expand significantly until
the World War II period when fuller's earth was used as an
absorbent for greases, oil, water, chemicals, and other
undesirable substances on the floors of factories, filling stations,
canning plants, aircraft hangers, decks and engine rooms of ships,
and other installations. The absorbent granules are porous and
ordinarily weigh less than 30 pounds per cubic foot; most
granules sold are (8 mesh and )60 mesh (U.S. standard-sieve
sizes). Because of their light weight, size, porosity, and absorbent
properties, the granules are suitable for many uses, and since
World War II, many different markets for them have developed.
Among other uses, they are now sold for litter and bedding for
poultry, pets, and other animals, as a soil conditioner in
greenhouses and for golf courses. In 1969, 620,000 tons of
fuller's earth was sold for absorbent uses; this tonnage was nearly
63 percent of the total fuller's earth produced in the United
States that year.
The foregoing discussions apply only to those uses consuming
sufficient quantities of fuller's earth to be classified separately
by the U.S. Bureau of Mines in the Minerals Yearbook. In
addition, smaller quantities of fuller's earth are or have been
produced for many miscellaneous uses. According to Oulton
(1965,p.5), more than 90 different grades of fuller's earth are
produced. Some of these grades are used for pharmaceuticals
designed to absorb toxins, bacteria, and alkaloids; for treatment
of dysentery; for purifying water and dry-cleaning fluids;
dry-cleaning powders and granules; for the manufacture of NCR
(no carbon required) multiple-copy paper; for the manufacture
of wallpaper; and as extenders or fillers for plastics, paints, and
putties. Fuller's earth mined near Ellenton, Florida, was used for
making lightweight aggregate for the construction of concrete
barges during World War II (Calver, 1957, p. 80; Greaves-Walker,
Bugg, and Hagerman, 1951, p. 14, table 3). Still other uses of
fuller's earth and its suitability for uses in new products are
outlined by Haden and Schwint (1967) and Haas (1970).
Some reports also note that fuller's earth is used in making
cement. Probably the basis for these reports is the mining of the
Twiggs Clay Member of the Barnwell Formation near
Clinchfield, Georgia, and its use in making portland cement. It is
used for this purpose mainly to obtain the desired chemical
composition in the clinker from which the cement is made. The
classification of this clay as fuller's earth results from the fact
that the Twiggs Clay Member is mined for fuller's earth, and this
unit is widely known in Georgia as a source of fuller's earth.
The total production of fuller's earth in the United States
during the years 1895-1969 was 18.3 million tons, valued at
more than 325 million dollars. Florida was the leading fuller's
earth-producing State for many years after the first mine was
opened in 1895. Mining of fuller's earth began in Georgia at
Attapulgus in 1907, and for more than a decade Georgia ranked
second or third among the States in the production of this
commodity. Georgia became the leading State in production in
1924 and held this position for several years. In recent years, the
production of Georgia and Florida has been lumped, and the
relative standings of the two States are not available. Their
production, however, was 81 percent of the national total during
the 10-year period 1960-1969 (fig. 2) and was 72 percent of all
production since 1895, amounting to 13.2 million tons. The
value of the fuller's earth produced in these two States from
1960 to 1969 was 133 million dollars, which is approximately
86 percent of the national total
In 1971, seven plants were producing fuller's earth in Georgia,
and two others were under construction (table 1; fig. 3). In
addition, one plant operated by the Penn-Dixie Cement Corp, at
Clinchfield, Georgia, was using fuller's earth from the Twiggs
Clay Member of the Barnwell Formation in making portland
cement. Three fuller's earth plants were active in Florida, and
plants formerly existed at five other localities in this State (table
PATTERSON: FULLER'S EARTH AND BENTONITE
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GEOLOGY OF INDUSTRIAL MINERALS
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GEOLOGY OF INDUSTRIAL MINERALS
After a suitable fuller's earth deposit has been proved by
drilling and testing, the first step in mining is the removal of the
overburden. Bulldozers and scrapers are used for this purpose by
all companies active in the region, and one company uses a large
walking dragline powered with electricity to do much of its
stripping. Thicknesses of overburden stripped range from a few
feet to approximately 75 feet, but in some mines the maximum
overburden removed along ridge lines is as much as 100 feet
thick. Most of the overburden is sufficiently unconsolidated to
be loosened with a bulldozer, but in the southern part of the
Meigs-Attapulgus-Quincy district of Georgia and Florida (fig. 3)
some of the overburden consists of limestone and cemented
sandstone which must be blasted before removal with heavy
equipment. In most mines, overburden is removed in panels, and
after the earth in one panel is mined, the overburden from the
next panel is dumped in the mined-out area. After stripping, the
fuller's earth is loaded on trucks by dragline and hauled to the
plant. In the early part of the century, mine trams were used for
hauling, and some of the stripping was done by hydraulic
methods, but neither method has been used in recent years.
The raw fuller's earth, as it is delivered to the plant, contains
approximately 50 percent volatile matter, and some of it
contains as much as 10 percent undesirable impurities. The
volatile matter is chiefly free and combined water. The
processing of fuller's earth involves mainly crushing or slicing the
crude clay, drying or firing to drive off the volatile matter and
improve the desired properties, grinding, grading by particle size,
and packaging. Different commercial grades and products, each
with its own specific properties and applications are made by
varying the raw material and processing (Oulton, 1965, p. 5).
One plant uses an extruding process before drying to improve
the properties for certain products. In this process the crushed
clay is fed into a pug mill, and water is added to obtain the
desired plasticity. It is then extruded into rods which are
approximately % inch in diameter.
Drying in most plants is done in gas- or oil-fired rotary dryers,
which are as large as 10 feet by 65 feet, but one plant in Georgia
uses a fluid bed-type dryer. The temperature at which the clay is
dried or fied ranges from 300 to 12000F in the different
processing depending on the use of the product. In processing,
the clay is ground in rod or other types of mills and sized to
yield a variety of granular and pulverized grades. Some plants
that produce mainly absorbent granules actually beneficiate their
product by discarding the fines. This is possible because in some
deposits most of the impurities are in the sand and silt size and,
therefore, are distinctly finer than the granular-sized product.
Plants that produce many grades of pulverized and granular
fuller's earth commonly recycle their material, and the raw clay
processed is selected with considerable care. One of the products
resulting from selective mining and processing is 95 percent finer
than 10 microns in particle size.
The fuller's earth in the Southeastern States is scattered
throughout sedimentary rocks of Tertiary age, and small
quantities were mined many years ago from sinkhole fillings
which may be younger. Fuller's earth is now and has been mined
at several localities (tables 1 and 2; fig. 3, locations 3-6) from the
extensive Twiggs Clay Member of the Barnwell Formation of
Eocene age and from discontinuous deposits in this formation
which are probably younger than the Twiggs Clay (table 1; fig. 3,
location 2). The deposits mined most extensively, however,
occur in the Hawthorn Formation of early and middle Miocene
age. These deposits occur in large lenticular units and
discontinuous beds. The deposits mined range in thickness from
about 2 feet to as much as 47 feet. The most extensive
Hawthorn deposits are in the Meigs-Attapulgus-Quincy district,
Georgia and Florida (fig. 3). Fuller's earth in the Hawthorn
Formation is also mined near Lowell, Florida (fig. 3, location
24), and deposits in this formation were formerly worked near
Ellenton, Florida (fig. 3, location 25). Several decades ago,
fuller's earth was mined near Lumpkin, Georgia (fig. 3, location
7), and near Clayton, Alabama (fig. 3, location 9), from deposits
of Paleocene age (table 2). Shortly after the turn of the century,
small quantities of fuller's earth were produced near Salters
Depot, South Carolina (fig. 3, location 1), from beds that are
probably the ones in the Black Mingo Formation of Paleocene
and Eocene age referred to as opal claystone by Heron,
Robinson, and Johnson (1965, p. 19,20). Fuller's earth thought
to occur in sinkhole fill deposits and to be probably of
Pleistocene age (Jones, 1926, p. 128) was once mined on a small
scale near Fort Payne, Alabama (fig. 3, location 8).
The fuller's earth in the Southeastern States varies
considerably in clay-mineral composition and the quantity of the
mineral impurities present. The fuller's earth mined in South
Carolina many years ago probably was opal-bearing claystone
which forms much of the Black Mingo Formation. Part of this
claystone is almost pure opal and part is montmorillonite
(Heron, Robinson, and Johnson, 1965, p. 19, fig. 14). The
fuller's earth in the Barnwell Formation mined near Wrens,
Georgia, is probably mainly claystone consisting chiefly of opal
or cristobalite and montmorillonite (Sandy, Carver, and
Crawford, 1966, p. 21; Carver, this volume). The Twiggs Clay
Member of the Barnwell Formation, which has been the source
of fuller's earth at several localities in Georgia, consists mainly of
cristobalite or .opal and montmorillonite, but it contains minor
quantities of illite and kaolinite (Brindley, 1957; Heron,
Robinson, and Johnson, 1965, p. 59).
The fuller's earth in the Meigs-Attapulgus-Quincy district,
Georgia and Florida, has been investigated by the author and
several other geologists and mineralogists (see footnote, table 1
for references). Attapulgite is the dominant mineral in deposits
in the southern part of the district, and montmorillonite is very
abundant in the northern part. Opal and possibly other forms of
amorphous silica are common in the northern part of the district
and occur in the form of diatom remains and rare rounded and
ovoid concretions. Small quantities of the magnesian clay,
sepiolite, are commonly present, and kaolinite occurs in the
weathered parts of some deposits. Impurities are mainly plastic
quartz, dolomite, and calcite, and each of these are so sbundant
locally that deposits are bypassed in mining. Phosphate pellets
and plastic heavy minerals occur in trace amounts in most
deposits. The marine fossils present include diatoms, fish
remains, and pelecypods.
A sample of fuller's earth mined near Lowell, Florida, was
described by Grim (1933, p. 358) as being 90 percent
montmorillonite and 10 percent isotropic siliceous material and
grains of quartz, albite, and other feldspar. Other samples from
this area described by Espenshade and Spencer (1963, p. 20-21)
contained both montmorillonite and attapulgite. The deposit
mined also contains poorly bedded and irregular masses of opal
or another form of silica which is bypassed in mining and is
presumably the material referred to by Espenshade and Spencer
PATTERSON: FULLER'S EARTH AND BENTONITE
The so-called "calcium," "low swelling," or "southern"
bentonite, which is now produced mainly for bonding foundry,
sand, occurs in Coastal Plain rocks. Most of the "southern"
bentonite in Southeastern States is in Alabama, but it also has
been reported in South Carolina. The bentonite in Alabama is
mainly in strata of Late Cretaceous and early Tertiary age. The
deposits mined to supply a plant operated by American Colloid
Co. near Sandy Ridge, Lowndes County, since 1964 are in the
Ripley Formation, and they have been described by Monroe
(1941, p. 112-114). Deposits of clay referred to as bentonite by
Harper (1940, p. 43) and as bleaching clay by Bramlette, Bay,
and Munyan (in Lang and others, 1940, p. 232) occur in the
upper 10 or 15 feet of the Tallahatta Formation of middle
ocene age along the Tombigbee River near Cummingham,
Clarke County, Alabama. This clay was mined on a small scale in
he 1930's, but none has been produced at this locality in recent
years. The bentonite in South Carolina (Robinson, Buie, and
Johnson, 1961, p. 3, map) occurs in the Hawthorn Formation of
Miocene age. It is 15 to 20 feet thick over a large area in the
vicinity of Coosawhatchie, Jasper County. This clay has been
described as being almost pure montmorillonite (Heron,
obinson, and Johnson, 1965, p. 24; Heron and Johnson, 1966,
53-56). No mining of this bentonite has been reported, but
the results of preliminary tests indicate that it is suitable for use
as foundry-sand bond (Johnson, 1958, p. 97-98).
0Bay, H.X., and Munyan, A.C. 1935, The bleaching clays of
Georgia: Georgia GeoL Survey Inf. Circ. 6, 4 p.
iBrindley, G.W., 1957, Fuller's earth from near Dry Branch,
Georgia, a montmorillonite-cristobalite clay: Clay Minerals
Bull, v. 3, no. 18, p. 167-169.
Buie, B.F., and Gremillion, L.R., 1963, Attapulgite in fuller's
earth deposits of Georgia and Florida: Georgia Mineral
Newsletter, v. 16, nos. 1-2, p. 20-25.
Calver, J.L, 1957, Mining and mineral resources: Florida Geol.
Survey Bull 39, 132 p.
Espenshade, G.H., and Spencer, C.W., 1963, Geology of the
phosphate deposits of northern peninsular Florida: U.S.
GeoL Survey Bull 1118, 115 p.
Greaves-Walker, A.F., Bugg, S.L, Hagerman, RS., 1951, The
development of lightweight aggregate from Florida clays:
Florida Eng. and Indus. Expt. Sta. (Florida Univ. Eng.
Prog., v. 5, no. 9) Bull. 46, 23 p.
Gremillion, L.R., 1965, The origin of attapulgite in the Miocene
strata of Florida and Georgia: Florida State Univ., Ph.D.
thesis, 139 p.
Grim, R.E., 1933, Petrography of the fuller's earth deposits,
Olmstead, Illinois, with a brief study of some non-Illinois
earths: Econ. Geology, v. 28, no. 4, p. 344-363.
Haas, C.Y., 1970, Attapulgite clays for future industrial mineral
markets [abs]: Mining Eng., v. 22, no. 12, p. 63.
Haden, W.L., Jr., and Schwint, I.A., 1967, Attapulgite, its
properties and applications: Indus. and Eng. Chemistry, v.
59, no. 9, p. 58-69.
Harper, R.H, 1940, Statistics of mineral production in Alabama,
1926 to 1938: Alabama Geol. Survey Bull. 44, 55 p.
Heron, S.D., Jr., and Johnson, H.S., Jr., 1966, Clay mineralogy,
stratigraphy, and structural setting of the Hawthorn
Formation, Coosawhatchie district, South Carolina:
Southeastern Geology, v. 7, no. 2, p. 51-63, 1 fig.
Heron, S.D., Jr., Robinson, G.C., and Johnson, H.S., Jr., 1965,
Clays and opal-bearing claystones of the South Carolina
Coastal Plain: South Carolina State DeveL Board, Div.
Geology Bull 31, 65 p.
Hurst, VJ., Crawford, T.J., and Sandy, John, 1966, Mineral
resources of the central Savannah River area, v. 1-2:
Washington, D.C., U.S. Econ. DeveL Adm., v. 1, 467 p., v.
2, 231 p.
Johnson, H.S., 1958, Geological activities in South Carolina
during 1958: South Carolina State DeveL Board, Div.
Geology Bull, v. 3, no. 1, p. 89-101.
Jones, W.B, 1926, Index to the mineral resources of Alabama:
Alabama GeoL Survey Bull. 28, 250 p.
Kerr, P.F., 1937, Attapulgus clay Am. Mineralogist, v. 22, no. 5,
LaMoreaux, P.E., 1946, Geology and ground-water resources of
the Coastal Plain of east-central Georgia: Georgia GeoL
Survey Bull. 52, 173 p.
Lang, W.B., King, P.B., Bramlette, M.N., McVay, T.N., Bay,
H.X., and Munyan, A.C., 1940, Clay investigations in the
Southern States, 1934-35: U.S. Geol. Survey Bull 901,
McClellan, G.H., 1964, Petrology of Attapulgus clay in north
Florida and southwest Georgia: Univ. Illinois, Ph.D. thesis,
Miser, H.D., 1913, Developed deposits of fuller's earth in
Arkansas: U.S. Geol. Survey Bull. 530, p.207-220.
Monroe, W.H., 1941, Notes on deposits ofSelma and Ripley age
in Alabama: Alabama GeoL Survey Bull. 48, 150 p.
New Jersey Geological Survey, 1878, Report on the clay
deposits of the Woodbridge, South Amboy, and other
places: New Jersey GeoL Survey, 381 p.
Nutting, P,D., 1943, Absorbent clays, their distribution,
properties, production, and uses: U.S. GeoL Survey Bull.
928-C, p. 127-219.
Oulton, T.D., 1965, Mining, production, and uses of attapulgite
clay products: Am. Inst. Mining, Metall. and Petroleum
Engineers, Soc. Mining Engineers, Preprint 65H39, 10 p.
Parson, C.L., 1913, Fuller's earth: US. Bur. Mines Bull. 71, 38
Pickering, S.M, Jr., 1970, Stratigraphy, paleontology, and
economic geology of portions of Perry and Cochran
quadrangles, Georgia: Georgia Dept. Mines, Mining, and
Geology Bull. 81, 67 p.
Rich, A.D., 1960, Bleaching clay, in Gillson, J.L., and others,
eds., Industrial minerals and rocks (Nonmetallics other
than fuels): 3d ed., New York, Am. Inst. Mining, MetalL,
and Petroleum Engineers, p. 93-101.
Ries, H.R., 1927, Clays: their occurrence, properties, and uses,
with special reference to those of the United States and
Canada: 3d ed., New York, John Wiley and Sons, 613 p.
Robinson, G.C., Buie, B.F., and Johnson, H.S., Jr., 1961,
Common clays of the Coastal Plain of South Carolina and
their use in structural clay products: South Carolina State
Devel. Board, Div. Geology Bull. 25, 71 p.
Sandy, John, Carver, R. E., and Crawford, T. J., 1966,
Stratigraphy and economic geology of the Coastal Plain of
the central Savannah River area, Georgia, in GeoL Soc.
America, Southeastern Sec., Ann. Mtg., Athens, Ga., April
13-16, 1966, Guidebook, Field Trip No. 3: Athens, Ga.,
Univ. Georgia Dept. Geology, 30 p.
Sellards, E.H., 1908, Mineral industries: Florida GeoL Survey
Ann. Rept. 1, p. 26-53.
------ 1910, The fuller's earth deposits of
Florida: Mineral Industry, 1909, v. 18, p. 267-270.
------------, 1914, Mineral industries and resources of
Florida: Florida Geol. Survey Ann. Rept. 6, p. 21-114.
Sellards, E.H., and Gunter, Herman, 1909, The fuller's earth
deposits of Gadsden County, Florida, with notes on
similar deposits found elsewhere in the State: Florida
GeoL Survey Ann. Rept. 2, 1908-09, p. 253-291.
46 GEOLOGY OF INDUSTRIAL MINERALS
Shearer, H.K., 1917, A report on the bauxite and fuller's earth
of the Coastal Plain of Georgia: Georgia GeoL Survey Bull.
31, 340 p.
Shrum, R.A., , Distribution of kaolin and fuller's earth
mines and plants in Georgia and north Florida: Georgia
Dept. Mines, Mining, and Geology, map.
Silliman, Benjamin, 1820, Art. III. Sketches of a tour in the
Counties of New Haven and Litchfield in Connecticut,
with notices of the geology, mineralogy, and scenery, etc.:
Am. Jour. Sci., v. 2, no. 2, p. 201-235.
U.S. Bureau of Mines, Minerals Yearbooks, 1927-1969.
Vaughn, T.W., 1902, Fuller's earth of southwestern Georgia and
western Florida: U.S. GeoL Survey, Mineral Resources of
the United States, 1901, p. 922-934.
Vaughn, T.W., 1903, Fuller's earth deposits of Florida and
Georgia: U.S. GeoL Survey Bull. 213, p. 392-399.
Zapp, A.D., and Clark, L.D., 1965, Bauxite in areas adjacent to
and between the Springvale and Andersonville districts,
Georgia: U.S. Geol Survey Bull. 1199-H, 10 p.
PATTERSON: FULLER'S EARTH AND BENTONITE
Figure 1. Fuller's earth sold or used by producers for specified uses, 1927-1969.
1930 1940 1950 1960
GEOLOGY OF INDUSTRIAL MINERALS
1900 1910 1920 1930 1940 1950
Figure 2. National and Georgia-Florida production of fuller's earth and average value per ton, 1895-1969.
PATTERSON: FULLER'S EARTH AND BENTONITE
A Active fuller's earth plant A6 Cement plant using fuller's earth
O Inactive or dismantled fuller's earth 0 Active bentonite plant
plant or inactive district 9 Inactive bentonite plant
Numbers refer to localities in tables 1 and 2
Figure 3. Location of active plants producing fuller's earth and bentonite and inactive plants and districts.
VERTICAL VARIABILITY IN THE ATTAPULGITE MINING AREA
Charles E. Weaver and Kevin C. Beck
School of Geophysical Sciences
Georgia Institute of Technology
A core from the La Camelia attapulgite mine in north Florida was studied in detail to determine the detailed vertical
variability and the relations of the various parameters. The structural, textural, mineralogical and chemical data indicate there
are two major depositional cycles represented within the minable interval. The sediments deposited during the two cycle differ
in detail but in general are similar. The environments of deposition grade from shallow marine to lagoonal to tidal flat to
The sedimentary structure (lamination, burrows, pebble conglomerate), mineralogy (attapulgite, montmorillonite, sepiolite,
dolomite, calcite) chemistry (Al, Mg, Fe) are closely related to each other and their nature is determined by the depositional
Most of the clay minerals and carbonate minerals are authigenic and are therefore particularly sensitive to environmental
The variability and environmental features seen in this core are characteristic of the sediments in the general attapulgite
mining area. A detailed understanding of the relationships discussed should be of value in prospecting, mining and processing.
For several years the authors have been making a regional
stratigraphic, petrographic, and geochemical study of the
Miocene of the southeastern United States. This paper reports
the results of a detailed study of one core from the commercial
The core was studied in detail in an attempt to find
parameters that could be used to identify depositional
environments. This information in conjunction with other data
can be used to determine the physical and chemical conditions
under which the authigenic attapulgite, montmorillonite, apatite
and dolomite form.
From a more practical standpoint, studies of this type should
be of value in exploration, mining, and processing.
The 28 foot core was a production core from near the
Engelhard Minerals and Chemicals Corporation, La Camelia Mine
near Attapulgus, Georgia. The core was kindly supplied by the
company. The clay mined in this area is relatively pure
attapulgite of Miocene age. The formation is considered to be
Figure 1 is a generalized litholoPic description of the core.
There are two pure clay beds (1.6 to 4.8' and 20.0' to 23.8')
that consist of relatively pure, parallel laminated clay (figure 2).
Though these clay beds are generally similar, they have a number
of significant mineralogic differences. Each clay interval is part
of a lithologic sequence; both sequences or cycles differ.
The lower interval starts with a clayey sand. This is followed
by a thin interval of mud cracked clay infilled with a coarser
sandy clay (figure 3). Some of the pebbles are partially
dolomitized. There is another thin sandy zone with clay pebbles
and then the clay bed proper. There is a thin sand zone in the
middle of the clay bed and some worm burrows near the top.
This is followed by another bed of reworked (with little
movement) clay pebbles in a matrix of coarser sandy clay (figure
4); round sand size clay grains are also abundant in this bed.
This bed is overlain by' a sandy clay bed with a vertical,
slightly slickensided fracture pattern (figure 5). Many fractures
are coated with a thin film of clay. The lower half contains
organic stains and clay grains and the upper half burrows.
Treatment with NaOH indicates much of the organic material is
in the form of humic acid. This interval may represent a soil or
marsh zone and appears to be the uppermost position of the
lower cycle. For the sake of convenience it will be referred to as
This interval is overlain by a sandy bed which is a greenish
clayey sand with irregular mottles of white sand and worm tubes
(figure 6). This interval is overlain by a white sand containing
pelecypode shells. The mixing in the lower part of the sand is
apparently due to both burrowing and current action.
There is a gradual transition from sand to dolomitic clay
(11.5' to 9.3'). A pure clay bed containing patches of dolomite
extends up to 8 feet. At 7.6 feet dolomite becomes predominate
and there is 2.8 feet of clayey dolomite (figure 7). The dolomitic
bed is overlain by 3.2 feet of pure clay. The lower two-thirds has
excellent parallel bedding; the upper one-third has an irregular,
massive appearance with some irregular vertical fracture surfaces.
This clay bed grades into an interval which consists largely of
the same type of clay, but heavily burrowed and infilled with a
coarser clayey sand (figure 8). This is the top of the core. It is
overlain by a clayey sand similar to the type that occurs in the
burrows in the top of the core.
Thus on gross lithology, there appears to be two similar, but
different, depositional units. Both units appear to be topped by
a hiatus of some sort, and both start with a sand bed of probably
marine origin. The lower unit is characterized by mud cracked
and locally reworked sediments and the upper unit by dolomitic
Attapulgite is the predominate clay in the section.
Montmorillonite is second in abundance followed by sepiolite.
Illite and mica are present in minor amounts throughout the
section. The estimated relative clay mineral content, based on
x-ray patterns of oriented slides, is shown in figure 9.
The clay mineral suite is closely related to the lithology and
thus presumably depositional environments. In addition, there
are significant differences between the upper and lower
The clay in the basal sand is largely montmorillonite with
minor amounts of attapulgite and trace amounts of sepiolite.
The amount of attapulgite systematically increases and
montmorillonite decreases upward, through the clay bed, to the
top of the lower clay bed (20 feet). Attapulgite remains
relatively constant or decreases slightly through the pebbly clay
zone then decreases abruptly in the overlying sandy zone.
Sepiolite is present throughout the lower section.
In the pebbly zone (20 to 16.5 feet) the pebbles have a high
attapulgite content; the clayey sand matrix is composed largely
GEOLOGY OF INDUSTRIAL MINERALS
of montmorillonite (figure 9). Small (0.1 to 0.2 inch) rounded
tan pebbles are similar in composition to the large mud
crack-type blocks. Sepiolite is present throughout this interval in
the clay pebbles and grains but not in the matrix. The clay suite
of the matrix is similar to that of the overlying montmorillonitic
sand zone. If the matrix and pebble values are averaged the
percent montmorillonite trend tends to parallel that of the
percent quartz (figure 14).
Montmorillonite is uniformly high, and has a maximum
concentration in the soil zone. Also, sepiolite reaches a
maximum at the bottom of the soil zone and is not present in
the overlying sediments. This is the only interval that contains
more sepiolite than attapulgite.
A detailed study of the bottom part of the soil zone indicates
that the clay mineral suites are inhomogeneously distributed.
The greenish sandy clay is composed almost entirely of
montmorillonite, with variable amounts of biotite. Some small
white pebbles have a composition similar to the underlying large
pebbles (attapulgite) montmorillonite) sepiolite). Also present
are some small tannish grains (0.1 0.2 inches) and a thin tannish
coating on the vertical fracture surfaces. In both of these types
of samples montmorillonite is the dominant clay and sepiolite is
more abundant than attapulgite.
Thus the "sepiolite-rich" suite has a distinctive occurrence.
The distribution suggests the clay may be secondary and have
formed by post depositional leaching of the upper part of the
soil interval and growth in the bottom.
Tannish grains in the upper portion of the soil zone are
composed almost entirely of attapulgite, sometimes with
dolomite. Thus pebbles in the lower portion of the soil interval
have a mineral suite similar to the underlying section and those
in the upper portion resemble the overlying section.
Burrows in the 13 to 16 foot montmorillonite-rich interval are
composed largely of attapulgite indicating clay has been worked
down from as much as 5 or 6 feet above. No sepiolite is present
so the clay has not come from below. The burrows contain no
dolomite which suggest that either the animals selectively
by-passed the dolomite rhombs or that a clay bed has been
eroded and replaced by the sand at 11 to 13 feet.
In the overlying shelly sand zone attapulgite increases and
becomes relatively abundant within the sand; however, the
mottles and pebbles of greenish clayey sand in this interval have
a high montmorillonite content similar to that of the underlying
interval Thus some of the mixing is probably due to current
reworking of the lower material into the upper, rather than
burrowing which would cause a downward mixing. The large
shells in this interval (11-12 feet) have been converted to
dolomite suggesting that there was a relatively abrupt increase in
Through the transition interval from clayey sand to clay (11
feet to 8 feet) the attapulgite content remains high and constant.
Attapulgite is at a maximum through the dolomitic and upper
clay bed. There is a slight decrease in attapulgite in the clays of
the uppermost burrowed zone. The burrows are filled with a
sandy montmorillonite clay derived from the overlying
montmorillonitic sand bed.
Thus, in the upper interval attapulgite occurs in the basal sand
unit and over an interval of less than a foot becomes the
dominant clay present. The upper clay bed has more attapulgite
than the lower clay bed but as the lower bed contains sepiolite
the montmorillonite content of the two beds is about the same.
Electron micrographs were made of both replicated and
dispersed samples. Replicas of the attapulgite-rich pebbles from
the 25 foot interval show 0.5 to 1.0 p attapulgite laths or needles
and thin, uniform sheets of montmorillonite (figure 10). The
laths do not tend to form bundles and show little orientation,
one to another. In the lower clay bed the laths tend to form
bundles and there is a definite orientation pattern (figure 11).
The montmorillonite occurs as thin patches 0.5 to 1.0 pl in
diameter, the orientation pattern is more likely due to authigenic
growth than sedimentation. A few laths up to 10 p in length are
present. Most fibers are near 1 p in length but, throughout the
lower interval fibers longer than 5 p are present.
Samples from the soil zone show thin continuous sheets of
montmorillonite with scattered unoriented attapulgite laths.
High magnification pictures (figure 12), show that the
montmorillonite consists of thin laths 0.05 p wide and 0.25 p
long. Many of the montmorillonite laths are oriented parallel to
one another and are draped over the coarser attapulgite fibers.
This orientation suggests growth in place. The montmorillonite
flakes in the underlying interval are subsequent in shape and no
evidence of laths was noticed. At least in this core the
lath-shaped montmorillonite is apparently restricted to the soil
The overlying sandy and clayey sand interval contains 1 p long
attapulgite fibers with a fair degree of orientation.
In the dolomitic zone dolomite rhombs range from 0.1 p up
to 10 1p in width. The attapulgite laths have little obvious
orientation to each other and to the dolomite rhombs (figure
13). Interpenetrating rhombs indicate the dolomite is authigenic
The upper clay bed is composed of 1 p long fibers. There is
some orientation into bundles but the bundles have little
systematic orientation with each other. Small rounded particles,
averaging 0.1 p in diameter, are common. These may be
There is nothing in the electron micrographs to suggest either
clay mineral has formed by alteration of the other. The two
types of clay are intimately mixed but it is not obvious which, if
either, might be authigenic. In the attapulgite clay beds the
montmorillonite occurs as .1 to 1.0 p subsequent patches
intimately interlayered with the attapulgite. The restricted size
of the montmorillonite areas, the random distribution, and lack
of any continuous sheets suggest the montmorillonite may be
floccules that settled among the attapulgite laths. The random
orientation of the attapulgite aggregates is more apparent than
real. Some pictures (figure 11) suggest that in a given plane the
attapulgite laths are nearly'parallel but the next layer of laths
may be oriented perpendicular to the underlying layer.
Twenty one samples were sieved at half 4 intervals. The
samples were disaggregated by pounding with a vertical motion.
This tended to break the non-clay minerals from the clay with a
minimum of damage. The material greater than 4.30 ( and
coarser was considered to be the "sand" fraction. Microscopic
examination indicates most of the clay "broke-down" and
passed through the 325 mesh sieve. Figure 14 shows the amount
of non-clay material and its composition. The sands at the base
of each unit contain 60 to 80% sand, most of which is quartz.
The clay beds and dolomite bed contain from 0.3 to 7.2 percent
Texturally, the two major units are quite distinct. The lower
unit generally consists of a moderately sorted sand with a modal
value ranging from 3.1 to 3.5 ). The upper unit is characterized
by bimodal frequency curves. At about 15 feet depth the curves
become distinctly bimodal With a new coarser mode occurring
at 2.5 to 2.8 ). The beginning of this mode can be seen in the
sample from 16.5 feet. By 12 feet the finer mode is gone and an
even coarser secondary mode develops at 2.2 ). By 10 feet the
WEAVER AND BECK: VERTICAL VARIABILITY
sample resembles that at 15 bimodall, approximately equal
amounts of 2.8 and 2.2 4 material).
Samples from 8 to 9 feet have a single mode (3.1 4) but most
of the sand (5 to 7%) is calcite, probably authigenic. The 7 foot
dolomitic sample is bimodal with most of the coarse material
being calcite and the finer material quartz. The sample from the
top of the dolomitic interval is also bimodal with a coarse mode
occurring at 2.2 ). Both size materials are primarily calcite but
of a different morphology than the calcite in the underlying
sample. The non-clay material from the middle of the upper clay
bed is composed predominantly of silt size quartz.
The amount of quartz and the grain size increases in the top
part (one foot) of the clay zone where some burrowing is
evident. The coarse mode at 3.1 4 is presumably the quartz sand
which the burrowing organisms have brought down from the
overlying sand bed. The 3.8 ( very fine sand is the quartz sands
that was originally deposited with the clay.
Sorting values, means, etc. are not too meaningful as most
samples contain several minerals, some of which are detrital and
some authigenic. The calcite was dissolved from the sieved
fractions of two samples (25 feet and 19.5 feet) and frequency
curves constructed for the calcite (plus phosphate) fraction and
the quartz fraction (figure 15).
The non-clay portion (68.5%) of the clayey sand sample from
28 feet is composed almost entirely of quartz. It has a
symmetrical peak with a well defined mode at 3.2 4; sorting
value is j=0.81 or moderately sorted. The sample from the
overlying reworked zone (25 feet) contains 24.6% non-clay
material which consists of 59% calcite (plus minor phosphate)
and 41% quartz. The sorting (0q) value for the quartz component
is 0.51 which Folk (1968) classes as moderately well sorted. The
value for the combined samples is 1.33 or poorly sorted. The
calcite, apparently authigenic, has a coarsely skewed size
In this sample and in the other samples size distribution
parameters are closely related to mineralogy. The detrital quartz
in the lower interval, whether it comprises 67% or less than 1%
of the sample, is moderately sorted with a well defined
symmetrical mode at 3.2 to 3.5 4 (figure 16). As the
depositional environments indicate a wide range of energies were
operative the source area for the quartz sand must have had a
uniform texture throughout deposition of the lower unit.
The quartz in the sample from 19.5 feet (figure 17) has the
same modal value as the 25 foot sample but the sorting is slightly
poorer (O=0.58) with the quartz being skewed towards the
coarser size. This may reflect the presence of coarse volcanic
quartz (thin section) (figure 26). The HCI soluble fraction (11%,
with calcite being about twice as abundant as phosphate) has a
trimodal distribution which can also be related to mineralogy.
The coarsest mode is largely due to knobby appearing calcite
grains which may be aggregates. The two finer modes are due to
phosphate grains and a more well crystallized form of calcite.
Clear, perfect rhombs are common in the finer sizes.
The series of frequency curves (16.5 feet to 10.0 feet) in
figure 18 shows the textural, and transition from the lower
interval to the upper interval. In the soil zone between 16.5 feet
and 13.5 feet the proportion of the sand mode characteristic of
the lower interval decreases and a newer, coarser, but similarly
sorted, quartz sand suite increases. The amount of clay,
phosphate and calcite grains are not sufficient to account for the
new mode and most of the new, coarser mode is made up of
quartz sand, presumably from a metamorphic source (as
indicated by this section and heavy mineral studies).
At 13.5 feet where the mottled sand and shelly sand zone
starts the mode characteristic of the lower interval is completely
gone and the new mode at 2.8 P is dominant; however, this is
accompanied by an even coarser new mode at 2.3 ). This new
material is made up largely of clay grains, though there is
appreciable quartz in this size range.
As the clay-rich interval starts at about 10 feet, the two quartz
sand modes characteristic of the transition interval (16.5 feet to
11.3) reappear and comprise the bulk of the non-clay material.
Above this interval the amount of quartz is minor; also, it is
much finer, being mostly in the silt range.
The quartz in the upper clay bed is distinctly finer grained
than that in the lower clay bed (figure 19); the coarser mode in
the 3.5 foot sample is due to calcite. Extremely fine grained
quartz also characterized the underlying dolomitic body. The
coarser fraction in this interval is calcite.
In the interval which shows evidence of reworking (lower
interval) and burrowing (upper interval) the quartz in the matrix
clay tends to be coarser grained than in the indigeneous or
reworked material. As would be expected, the reworking
currents are probably of higher energy than those in the
environment in which the mud cracks formed and would carry a
coarser load of detrital material.
Also, the burrowing organisms appear to prefer a sandy
coarser grained substrate and then burrowing down into more
clayey material carrying coarser material with them.
COMPOSITION OF SAND GRAINS
The sieved fractions of the greater than 4.38 4 fraction
(non-clay fraction) was studied with the microscope and by
x-ray diffraction (figure 14).
Quartz is present in all samples and is generally highly
polished though much of the quartz in the sand samples from
13.5 feet to 10 feet have thin clay coating. Varying amounts of
K-feldspar is present in all but the upper two feet.
Well-rounded white to light tan phosphate grains (figure 20)
are present in amounts ranging from less than one to 15 percent
of the greater than 4.38 4 fraction in all samples but the top
burrowed zone. The phosphate in general is more abundant in
the lower interval (figure 14). Phosphate is two to three times
more abundant in the lower clay bed than in the upper clay bed.
The origin of the phosphate is not clear. The clayey sand interval
at 10 feet contains hollow cylinders, that appear to be worm
tubes, with the walls of the cylinders made of light tan apatite
(figure 21). This same interval contains paper thin flakes of
material that also appears to be apatite (larger sheets of
phosphate occur at 13 feet). Thus it appears that phosphate is
relatively abundant in the sandy interval between the two basic
depositional units. This phosphate is, at least indirectly, organic
in origin. This suggests that some of the round phosphate grains
could be locally deposited fecal pellets. The phosphate content
of the "non-clay" fraction of at least one sample (18 feet) is
nearly as high as that of commercial sands (approximately 20%
which indicates that a relatively minor winnowing could produce
commercial phosphate deposits from these sandy clay zones.
Calcite, in amounts ranging from 2 percent to 78 percent, is
present in nearly all but the upper two feet of the section. From
the bottom, up to nine feet, the calcite grains are generally
subequant in shape with some clear rhombs and a minor amount
of rice-shaped grains. The dolomitic unit, from nine to seven
feet, contains an abundance of distinctive rice-shaped calcite
grains (figure 22) that are apparently authigenic in origin. The
calcite in the upper part of the dolomitic zone and the upper
clay bed is largely subequant in shape.
Calcite is most abundant in the intervals which contain
Well-rounded clay grains (figure 23) are fairly abundant in the
central sandy interval and in the uppermost burrowed interval.
The clay grains are probably more abundant than indicated in
figure 14 as some probably broke up and others are so coarse as
GEOLOGY OF INDUSTRIAL MINERALS
not to be included in the sieve analysis. Visual examination of
the samples indicate clay grains range from silt size up to an inch
or more in diameter.
Samples from the upper clay and dolomitic zones and the
lower portion of the lower clay zone contain a few dark metallic
sand size grains that are probably ilmenite. Many have rusty,
Of perhaps more interest is the presence of authigenic pyrite.
The pyrite is in the form of rosettes (figure 24) and elongated
ovals. The pyrite is restricted to the upper clay and dolomitic
zone (7.5 to 1.5 feet). This suggests that reducing conditions
existed at some stages during deposition of this interval
The major differences in the two clay beds is the presence of
pyrite in the upper bed and none in the lower and the presence
of more phosphate in the lower bed.
Thin section studies indicate the basal clayey sand has
approximately 2 percent K-feldspar. The sand is composed
largely of plutonic quartz and a minor amount embayed quartz
which is presumably volcanic in origin. Minor phosphate is also
present. The sand grains are floating in a clay matrix and there is
little grain-to-grain contact. Presumably the clayey sand has been
completely reworked by burrowing organisms or it was
deposited abruptly in a low energy environment with little or no
reworking. A third possibility is that the sand was periodically
transported by winds or water into a quiet area where a clay gel
was being deposited. The most likely environments are shallow
marine or tidal
The clay in the lower clay bed is very well oriented parallel to
the bedding and was deposited in a low energy environment.
Near the top of the bed thin (2-4 grains thick) horizontal
laminae of quartz grains (figure 25) are relatively common.
These lamina also contain some clay and phosphate grains; the
clay grains appear to be montmorillonite; the matrix of the
lamina consists of unoriented attapulgite clay similar to that in
the clay bed. The detritus in these lamina was presumably
carried into the low energy environment (lagoonal) by wind or
relatively gentle periodic water currents.
The matrix material in the pebbly zone overlying the clay bed
consists of clayey sand and sandy clay. K-feldspar, phosphate
and clay grains are relatively common. Large, embayed, volcanic
quartz grains are common (figure 26). A few composite,
metamorphic quartz grains are present in this interval and in the
overlying sands. These are not present in the basal sand which
suggest there was a partial change in the source area during
deposition of these sediments.
The patchy, irregularly mixed green and white sand at 15 feet
is poorly sorted. Volcanic and metamorphic quartz grains are
present. Much of the clay and some clay grains appear to be iron
stained and show little orientation.
The dolomitic, sandy clay (9.5 feet) contains scattered
rhombs of dolomite (figure 27). The rhombs are idiomorphic
and many have dark centers that appears to be organic material.
A few aggregates of fine dolomite are present but most occur as
isolated rhombs. Thin lamina are present which contain quartz,
phosphate and calcite grains that are rice-shaped. These same
types of grains ( 10 percent) occur scattered throughout the
clay. The clay is relatively well oriented. The clay shows no
particular orientation with respect to the coarser grains with the
exception of one large phosphate grain (figure 27). A relatively
wide band of clay is oriented parallel to the grain boundaries.
It would appear that the dolomite grew in the clay mud
penecontemporaneously or else was washed in from a nearby
environment. On a megascopic scale much of the dolomite
occurs as patches and nodules suggesting that it formed in place.
In the overlying clayey dolomite interval (5 feet to 7.5 feet)
there is a fair amount of grain to grain contact but the rhombic
shape is maintained. In addition to organic (?) centers some of
the larger rhombs have carbonate cores (figure 28), probably
dolomite according to x-ray data. The rhombs range in size from
less than 0.005mm to .025mm with most being 0.015mm. Even
though some of the grains are relatively large it is unlikely that
they have a replacement origin; however, the shells in the
underlying sandy interval are composite of the similar type of
dolomite indicating that replacement has taken place in some
intervals of the section.
The clay in the overlying clay bed is highly oriented in a
horizontal direction except for the upper part (1.5 to 2.5 feet)
which has a patchy pattern with the clay in the patches being
well-oriented (figure 29). A few thin veins of montmorillonite
are also present. This interval appears to have been reworked,
probably by burrowing organisms, and a minor amount of clay
has been carried by water from the overlying montmorillonitic
This bed grades upward into an obviously burrowed interval
(figure 30). The attapulgite clay contains abundant burrows
containing a sandy montmorillonitic clay and pebbles and grains
of attapulgite. Much of the burrow material and some of the
attapulgite pebbles have a dark brown stain which may be iron
and/or organic material but appears to be a thin film of
montmorillonite. Most of the burrowed material has been carried
down from the overlying montmorillonitic sandy clay (not
present in the core). The intense burrowing suggest there was a
hiatus between the deposition of the upper attapulgite clay bed
and the overlying montmorillonitic marine section.
In order to determine if volcanic material was a major source
material, the heavy minerals were collected from the lower (23
feet) and upper (3 feet) clay beds and the soil zone.
The lower clay bed contains significant amounts of zircon,
tourmaline, rutile, apatite, staurolite, kyanite and sillmanite. The
heavy mineral suite suggest a mixed metamorphic-igneous source
with, probably, relatively little volcanic material. Phosphate
grains are common and many of them contained diatom
fragments (figure 31). As diatoms have not been found in this
section (but do occur further to the North). The phosphate is
presumably detrital A few phosphatic grains with concentric
growth rings are observed.
The heavy mineral suite from the soil zone is similar except
that the metamorphic suite was relatively more abundant. Thin
section examination also indicates metamorphic quartz is more
abundant in this section. This new source material presumably
accounts for the occurrence of bimodal frequency curves in this
interval (figure 18).
Most of the heavy minerals from the upper clay bed are
opaques. A few grains of tourmaline are found. Round
phosphate grains commonly contain fine grains of quartz and are
darker than those in the lower bed. No phosphate grains with
diatom fragments were found.
Thus, there is little evidence that volcanic material was a
major source of the sediments in this section. The heavy
minerals, particularly phosphate, give further indication that the
upper and lower clay beds were deposited under slightly
X-ray analyses were made of bulk samples randomly packed in
aluminum holders. It did not seem necessary to determine the
absolute amount of non-clay minerals present so only relative
numbers were determined (figure 32). The height of the
following peaks were measured: quartz 4.27A feldspar 3.24A,
calcite 3.03A, dolomite 2.90A. The relative proportion of each
were calculated. Apatite peaks were detected in most patterns
WEAVER AND BECK: VERTICAL VARIABILITY
but comprised less than five percent in all except a few selected
The (10T4) reflection of the dolomite ranges from 2.90A to
2.91A rather than the ideal 2.89A. These peaks are also
relatively broad. The material is poorly crystallized and
apparently contains 5 percent or more excess CaC03. The
dolomite or protodolomite is typical of the authigenic and
penecontemporaneous dolomite found in recent sediments. The
shells in the 11 to 12 foot interval are composed of a similar
K-feldspar is relatively abundant in the interval below 11 feet;
however, there is little sand above this depth. Dolomite is
concentrated in the interval between eleven and four feet and is
virtually absent below this depth except for some dolomitic
pebbles at 25 feet. Solubility data indicates the sample from five
feet contains 53 percent dolomite and one from seven feet 61
percent dolomite. There is a thin pure attapulgite clay bed (8.5
feet to 9.5 feet) within the dolomite interval, however, there are
patches of dolomite in the clay.
Thin shells in the 11 to 13 feet interval are composed of
dolomite indicating some replacement of calcite has occurred.
Calcite is a major component in several samples. The calcite is
granular and occurs as thin crust and fracture fillings.
Nearly pure phosphate, consisting of poorly crystallized
apatite, occurs in a few thin, one inch square particles in the top
six inches of the soil zone (and in smaller particles through the
upper foot of the zone). No phosphate was detected in the lower
soil zone but it was detected in over half the samples below this
zone. Above the soil zone it was found as a minor component of
only two samples (5 feet and 5.5 feet). Phosphate is appreciably
more abundant in the lower lithic sequence than the upper.
Chemical analyses (atomic absorption) were made of the
material scrapped from the slides used for x-ray analyses. This
was done so that the chemical data could best be related to the
In general Al 03 and MgO are inversely related (figure 33).
The A1203/MgO ratio is relatively high (5) in the basal sands and
decreases to a value of approximately 1.5 in the lower clay bed.
Pure attapulgite from this area has a ratio "1.0. The ratio reflects
variations in the relative amounts of montmorillonite plus
feldspar (Al203) and attapulgite, sepiolite and dolomite (MgO).
In the pebble intervals the pebbles have a low ratio and the
montmorillonite ratio has a high ratio. The ratio is highest in the
montmorillonitic soil zone, being a maximum at 15 feet near the
center of the zone. The ratio systematically decreases upward
reaching a minimum (0.5) in the dolomitic zone. The ratio is
lower and the absolute amount of Mg is higher in the upper
section than the lower section. Even though the MgO-rich clay
sepiolite (Al203/MgO = 0.1) is relatively abundant in the lower
clay bed the upper clay bed has a larger percentage of MgO. Thus
presumably something other than Mg ion concentration
determines whether sepiolite or attapulgite will form.
The Fe23O values (figure 33) are at a minimum (1.0 1.5%) in
the lower sand and the upper dolomite zone. The maximum
amount (6%) occurs near the base of the soil zone and is
relatively high through the soil and overlying sand zone. This
could be interpreted as evidence for a soil leaching profile. There
is little difference in the Al203/Fe203 ratio of the upper and
CaO values are relatively constant at 1-2% except for the
dolomitic zone where 8 to 10% is present.
The K20 distribution is similar to that of A1203. The upper
sequence has K2 0 values close to 0.5%, the values for the lower
sequence average 0.75%. Higher values, 1.0 to 1.7% occur in the
soil zone where the mica content is relatively high. The highest
value occurs at 13 feet reflecting a high K-feldspar content.
In order to botain some idea of the vertical variation in the
composition of the interstitial water and to see if it was in
equilibrium with the mineral suite, 10 grams of dry clay was
washed with distilled water and the water analyzed.
The distribution of cations is fairly uniform throughout the
section. Ca is the dominant cation comprising 48% to 62% of the
cation suite. There is a slight but systematic decrease in Ca with
depth. Mg values range from 21 to 27% and also decrease slightly
with depth. Na (5 to 14%) and K (7 to 16%) are present in
approximately equal amounts and both increase slightly with
depth, the Na more than the K.
The high Ca content and the decrease with depth suggest the
calcite (largely in shells) in the overlying section controls the
chemistry of the downward percolating rain water. It also
accounts for the secondary calcite filling fractions and coating
on bedding plains. The process probably has been going on since
Table 1 summarizes the differences between and the
similarities of the two depositional units.
It is evident from the study of this one core that these
Miocene sediments were deposited in a shallow water
environment near the strand line. An environmental
interpretation based on the study of one core is of questionable
validity and a final interpretation will be deferred until the more
comprehensive study is complete; however, enough regional
work has been done to present a preliminary interpretation.
In general the montmorillonitic sandy intervals appear to be
of shallow marine origin. The horizontal bedded clay-rich
attapulgite beds must have been deposited in a quiet lagoon,
probably hypersaline; the dolomitic beds were deposited in a
similar environment possibly during periods of increased salinity
or decreased in available Si and Al.
The pebble and mud-crack beds represent lagoonal deposits
that were later reworked by invading marine currents and
sediment. The vertically oriented sandy, montmorillonitic,
organic clay bed appears to represent a marsh environment,
perhaps with some secondary soil-like weathering. Burrowing is
evident throughout but is particularly important in the
environments (shallow) closing the end of each depositional
The depositional cycles started off with a sand or sandy shell
bed which acted as barriers. Shallow water lagoons developed in
back of these relatively thin barriers. In some instances these
lagoons were evaporated to dryness and mud cracks developed.
When the barriers were breached clayey marine sands were
mixed with the mud clasts. This situation seemed to be
characteristic of the lower depositional unit. This lower unit is
topped by marsh-like sediments suggesting the overall unit is
regressive. This regression is followed by an abrupt transgression
(shelly marine sand) which might reflect only a minor lateral
shift of environments.
The upper depositional unit shows little reworking and a
relatively thick lagoonal sequence (dolomite and attapulgite clay
bed), which suggest a more permanent-type of barrier plus a
decrease in available Si and Al. This interval appears to end in a
shallowing regressive environment (burrows and reworking), to
be followed by a relatively abrupt marine transgression.
Thus, both depositional units appear to represent a seaward
migration of a shallow water marsh-lagoon-barrier sequence.
Whenever the migration was interrupted by a sustained marine
transgression a new cycle begins.
GEOLOGY OF INDUSTRIAL MINERALS
The lithology indicates that the lower unit was probably more
effected by physical energy (marine envasions) and the upper by
chemical energy (dolomite). The detailed mineral and chemical
differences between the two units likely reflect only minor
environmental and source differences; however, from a practical
standpoint these differences can be used to identify the different
clay beds and for stratigraphic interpretation and exploration.
This detailed data indicates that with the accumulation of
additional data the chemical and physical conditions which
favored the formation of the various authigenic minerals in this
Miocene section can be specified in detail.
The study was supported by the National Science Foundation,
Grant GA-1330. The authors wish to thank Mr. Jack Williams of
the Engelhard Minerals and Chemicals Corporation for supplying
the core and giving background information. Horace Bledsoe
obtained some of the laboratory data.
Folk, RL. 1968, Petrology of Sedimentary rocks: Hemphill's,
Austin, Texas, 170 p.
WEAVER AND BECK: VERTICAL VARIABILITY
of clay dis-
Shells in basal sand
Burrowed unit at top
mont. to attap. occ.
within basal sand
Upper unit pred.
Attap. cont. higher
Mud cracks & clay
Soil at top
Basal sand thicker
Phos. worm tubes
Higher MgO content
Lower Al203/MgO ratio
Relatively high inter-
stitial Ca and Mg
interstitial Na & K
in basal sand
Qtz. in clay
bed finer and
in clay bed
GEOLOGY OF INDUSTRIAL MINERALS
pebbley clay with
vertical burrows and
fractures filled with sandy clay
fine clayey dol.
horz. laminated clay
from sd. to clay
It. gray sd.
green clayey sd.
white sd. patches and
clayes sd. vertical irreg.
sickensides, mica ab.
worm burrows, clay grains
pebbles in clayey
ab. sd. size clay grains
round clay grains
clay, worm burrows
clayey sd. matrix cal.
and clay pebbles
v. clayey sd.
flat clay pebble
cgl. clayey sd. matrix
Figure 1. Generalized lithologic description of core from La Camelia Mine, North Florida.
WEAVER AND BECK: VERTICAL VARIABILITY
* ~d-~~i*.-~ ;sy4.
* '' 't
S "' ': '1
*.. .' .
'y : '
Figure 2. Horizontally laminated attapulgite clay from lower clay bed (23 feet).
GEOLOGY OF INDUSTRIAL MINERALS
~ -. 4: .e
.. '. 1 '
.. .^ *
'^~ SB ;
. -'- ,.L Z
Figure 3. Mudrocks in attapulgite clay infilled with sandy montmorillonitic clay (25 feet).
:5; r -
* I* i*
'*' ~ ~ `T 3?' 'f f ^'"
WEAVER AND BECK: VERTICAL VARIABILITY
">^ I* *
Figure 4. Side view of horizontally laminated and mud-cracked attapulgite clay infilled with sandy montmorillonitic clay (19 feet).
" *I. 4!. .
1 .. ~
GEOLOGY OF INDUSTRIAL MINERALS
4 t .'I
Figure 5. "Soil" sample with vertical fractures and vertical sandy burrow (16 feet).
WEAVER AND BECK: VERTICAL VARIABILITY
- .:. .
. . .
(~ r~f~ ~c
-*- C -t .
Figure 6. White and green mottled sand with clay clast (13 feet).
GEOLOGY OF INDUSTRIAL MINERALS
Figure 7. Horizontally laminated attapulgite containing dolomite (5.5 feet). Lamination is apparent only after desicatinn.
WEAVER AND BECK: VERTICAL VARIABILITY
#,Ntr ..-- -.'. 4 ;' .. -t
,' '.4 .'
S,-. ... ..
l lc o*^ ...:?-. ^,. c- ,. .- .,
.^, -t:. A. .
:^ .Ji~E 1.4 q
Figure 8. Attapulgite clay containing burrows filled with sandy montmorillonitic clay and light colored fragments of attapulgite clay (1 foot).
GEOLOGY OF INDUSTRIAL MINERALS
Figure 9. Distribution of clay minerals.
WEAVER AND BECK: VERTICAL VARIABILITY
c/0o-Xo4(.Ol4e- # 0# ) -(-?-/?
#1/ 1700 x
Figure 10. Electron micrographs of clay clast (25 feet) showing attapulgite laths and thin patch of montmorillonite (46,700x).
GEOLOGY OF INDUSTRIAL MINERALS
caa 0(6 -9,- I -/-09
6 9, ?so x
Figure 11. Bundles of attapulgite laths from lower clay bed (22 feet). Thin patches of montmorillonite are also present (69,800x).
,V- r-6 ,
WEAVER AND BECK: VERTICAL VARIABILITY
Figure 12. Sample from soil zone (15 feet). Montmorillonite is in the form of thin ribbons. Attapulgite bundles are relatively small. (88,300x).
GEOLOGY OF INDUSTRIAL MINERALS
'&0 0 1(s4oOX-q- /,
Figure 13. Interpenetrating dolomite rhombs in attapulgite matrix (7 feet). (10,400x).
WEAVER AND BECK: VERTICAL VARIABILITY
% GREATER THAN 4.38 0
10 20 30 40 50 60 70
Figure 14. Amount and composition of the coarser-than 325 mesh material. The bars in the left graph show the total amount of greater-than
325 mesh material. The vertical connecting line indicates the amount of quartz in each sample. The right graph shows the composition, in
percent, of each sample.
GEOLOGY OF INDUSTRIAL MINERALS
1 2 3 4 5 6 7
Figure 15. Frequency distribution curves of the matrix sandy clay sample from 25 feet. Broken-line curve is for total sample. The other two
curves show the distribution for quartz and calcite grains.
WEAVER AND BECK: VERTICAL VARIABILITY
figuree 16. Frequency distribution curves for non-clay grains of basal sand and lower clay bed. Sand from 28 feet constitutes 68.5 percent of
ample. Sand fraction from 25 feet constitutes 1.6% of sample.
GEOLOGY OF INDUSTRIAL MINERALS
0 1 2 3 4 5 6
Figure 17. Frequency distribution curves of the matrix sandy clay sample from 19.5 feet. Broken-line curve is for total sample. The other two
curves show the distribution for quartz and calcite. The trimodal distribution of calcite is due to the presence of several types of calcite.
WEAVER AND BECK: VERTICAL VARIABILITY
Figure 18. Series of frequency curves of samples from the transition interval between the two major depositional units showing the systematic
development of coarser modes with decreasing depth.
76 GEOLOGY OF INDUSTRIAL MINERALS
0 1 2 3 4 5 6 7
Figure 19. Frequency curves of the greater-than 325 mesh material from the upper and lower clay beds. The modal values for the shallower
samples must be in the fine silt size range.
WEAVER AND BECK: VERTICAL VARIABILITY
Figure 20. Round phosphate grains (dark grains in the 19.5 foot sample).
GEOLOGY OF INDUSTRIAL MINERALS
Figure 21. Phosphatic (poorly crystallized apatite) cylinders in the 10.5 foot sample. Cylinders are probably organic in origin.
~a~Ba~ sis ,
WEAVER AND BECK: VERTICAL VARIABILITY
I & 1"_'
Figure 22. Rice calcite crystals (9 feet); calcite formed after initial deposition of sediments.
GEOLOGY OF INDUSTRIAL MINERALS
Figure 23. Clay (white) and quartz grains in 18 foot sample.
WEAVER AND BECK: VERTICAL VARIABILITY
Figure 24. Pyrite rosette in the 3.5 foot sample.
82 GEOLOGY OF INDUSTRIAL MINERALS
Figure 25. Thin, sandy laminae in upper portion of lower clay bed (20.5 feet).
WEAVER AND BECK: VERTICAL VARIABILITY
Figure 26. Large quartz grain with embayment; probably volcanic in origin. Rounded darker grains are phosphate (19.5 feet).
I Rab. N
;r; -. it. 1
*-s -. .-.1a
84 GEOLOGY OF INDUSTRIAL MINERALS
. 0 "-e,-
*- v -V.~ -esms
Figure 27. Dolomitic (white rhombs) attapulgite clay with phosphate grain (black). Clay is oriented with respect to phosphate grain (9.5 feet).
WEAVER AND BECK: VERTICAL VARIABILITY 85
iP .. % f 4
Figure 28. Clayey (attapulgite) dolomite. Many rhombs have dark organic centers; some, near center, have dolomite centers (7 feet).
86 GEOLOGY OF INDUSTRIAL MINERALS
I "?' _(c
P4 4Ve 3
Figure 29. Irregular patches of oriented attapulgite from top of upper clay bed (2 feet).
WEAVER AND BECK: VERTICAL VARIABILITY
Figure 30. Sand filled burrow and grains of attapulgite clay (1 foot).
GEOLOGY OF INDUSTRIAL MINERALS
Figure 31. Round phosphate grain with diatom (27 feet).
WEAVER AND BECK: VERTICAL VARIABILITY
RELATIVE AMOUNT OF NON-CLAY MINERALS
10 20 30 40 50 60 70 80 90
Figure 32. Relative amount of non-clay minerals based on x-ray analysis of bulk samples.
GEOLOGY OF INDUSTRIAL MINERALS
A1203 Mg 0 Fe203
I n 1 5
Figure 33. A1203, MgO, Fe203 distribution. Broken-line graph connects A1203/MgO values.