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Mining and mineral resources ( FGS: Bulletin 39 )
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Title: Mining and mineral resources ( FGS: Bulletin 39 )
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Full Text







STATE OF FLORIDA

STATE BOARD OF CONSERVATION
Ernest Mitts, Director


FLORIDA GEOLOGICAL SURVEY
Herman Gunter, Director







GEOLOGICAL BULLETIN NO. 39







MINING AND MINERAL RESOURCES






JAMES L. CALVER








Published for
THE FLORIDA GEOLOGICAL SURVEY
Tallahassee, 1957





s(- 7. 67




FLORIDA STATE BOARD

OF

CONSERVATION


LeROY COLLINS
Governor


R. A. GRAY
Secretary of State


RAY E. GREEN
Comptroller


THOMAS D. BAILEY
Superintendent Public Instruction


RICHARD ERVIN
Attorney General


J. EDWIN LARSON
Treasurer


NATHAN MAYO
Commissioner of Agriculture


ERNEST MITTS
Director of Conservation






LETTER OF TRANSMITTAL


-fIorioa geoloqicai Survey

C(allazassee
November 1, 1957

MR. ERNEST MITTS, Director
FLORIDA STATE BOARD OF CONSERVATION
TALLAHASSEE, FLORIDA
SIR:
This report entitled, "Mining and Mineral Resources," prepared
by Dr. James L. Calver, Geologist, with the Survey from 1947 to
May 1, 1957, is transmitted with the recommendation that it be
published as Florida Geological Survey Bulletin No. 39. The Study
is broad in its scope and contains practical discussions of the geo-
logic occurrence, economic development and utilization of Florida's
mineral resources. It is written in language understandable to the
interested inquirer, and this basic, authoritative information will,
I believe, assist materially in further development of our mineral
resources in Florida.
Under favorable economic conditions the raw mineral materials
of the State could be substantially developed and used by industry.
Florida's productive mineral wealth has increased in annual value,
as reported by the mineral industry, from nearly $15 million in
1940 to nearly $133 million in 1956. This remarkable increase has
broadened the tax base of the State. Florida currently ranks third
among all the states in the value of nonmetallic mineral production.
The Geological Survey sincerely appreciates your cooperation
and continued interest in its work.
Respectfully yours,
HERMAN GUNTER, Director












TABLE OF CONTENTS


Acknowledgments --_-_-- .....--

Introduction .--..--------------

General Statement ---
Conservation Practices ------
The Heavy Mineral Industry --
Review of Development -.
Monazite -- ---_ --
Zircon -------
Hafnium ------_--..... .-
Titanium Minerals (Ilmenite
Garnet -__- --.-----
Staurolite ...- ..----
Kyanite and Sillimanite ---

Peat ----- _----------------..--


and Rutile) ..

.. .. .. .. .. .. ... . ... ... ... . . .
..................................................-


Petroleum -..- -- ---------..__--- ......

Phosphate Rock -- --------
General Statement and Reserves --
River-Pebble and Land-Pebble ---
Mining and Processing -_--
Hard-Rock and Soft-Rock ...---......-
Uses -----------
Origin ---- -------.- .........

Aluminum --------

Portland Cement ....--_.. --------...

Clay ------
General Statement and Classification _
Kaolin --


Bentonite ...----
Fuller's Earth ---
General Properties --
Florida-Georgia District
Preparation --...---.-
Uses .........__. ------------.
Miscellaneous Clays ..-

Diatomite .--.---.-------

Lime -----_.-- --.

Fluorine ---. ....--

Gypsum ..--------

Radioactivity Surveys --

Lightweight Aggregates -
General Statement
Perlite and Vermiculite ------
Slag and Pumice --------------
Expanded Clay -------.... ...

Limestone -- --
Dimensional Stone ------...
Crushed or Broken Stone -


Page

-. .... ..... ..... 9

..- ... .. 11

--..--.... 11
-...--..--- 12

...........- -- 15
-------------------- 2
23
.... -- 25
.... 28
---------29
-30
-- 30
--..-- 30

..----- 31

----- 33

------ 34
34
------------------ 36
... 36
-38
--. ..- .....-- ... 48
-----. 48
-- -- 50

..... ... 50

52,
-- ------ ---.. ...- 56
--------------.--- 562
------ 56
--.........-- ....... 60
57
------------- -- -.--61
--------- 60'
-61
61
-63
-- ---- 64
---. ------ 66
.. .... -.. 67



----------.. 70

72

73:

74

-76
----..---- 76
---..- 77
78
----- ... 78

80'
.--. .....-- .... 80
-------- 8&


-----------------------------
-----------------------------
----------------------------
-----------------------------
-----------------------------
-----------------------------
-----------------------------


---------------
---------------
---------------


- - - - - - -


-----------------------------
-----------------------------
-----------------------------
----------------------------
-----------------------------

-----------------------------





Sand and Gravel ---__ .. ... .----- -------- 993
Sea Water and Brine ___------------------------- 95
Selected Bibliography --__-- ------ --------- 96
Index .-- --------- ------ ------------------- 126

ILLUSTRATIONS


Figures Page
1 Map of mineral resources and industries of Florida ___--__- In pocket
2 Graph illustrating the growth of Florida's mineral industry ------__- 13
3 Dredge and heavy mineral concentration barge, Florida Minerals
Company, Winter Beach, Indian River County -- __ ----- 17
4 Schematic flow-sheet of the Trail Ridge heavy mineral mine and
mineral separation plant ____-.--- _----____ ......--- --- ---- 20
5 Generalized flow-sheet of the Trail Ridge mine and plant 22
6 Suction dredge at the Trail Ridge mine, Clay County --_--- 23
7 Floating concentration plant at the Trail Ridge mine ---- 24
8 Back-fill or mined-out area at the Trail Ridge heavy mineral mine,
Clay County __--------____-------------- ---------- 24
9 Generalized flow-sheet of the Humphreys Gold Corporation's zircon
recovery plant at the Trail Ridge mine, Clay County ---- 27
10 Mining and loading peat at deposit located near Florahome, Put-
nam County ---------------------.- --- 32
11 Production record of the Sunniland Field, Collier County --------- 35
12 Sunniland Oil Field, Collier County, rework derrick ----- 37
13 Noralyn mine and plant of the International Minerals and Chemical
Corporation, Bartow, Polk County ___ ___.------------------ 40
14 Preparing matrix for pipeline transportation ___---- 42
15 Generalized flow-sheet of a land-pebble phosphate washer and flo-
tation plant _--------------___- -- ---- .---- 43
16 Index map to mines and plants in the land-pebble phosphate rock
district -..----------------------- 44
17 Kibler-Camp Phosphate Enterprise, Sec. 18 mine, Citrus County --- 51
18 Classification of clay minerals ...------- .- ---_..----... - 58
19 Dredge of the Edgar Plastic Kaolin Compy pit, Edgar, Putnam
County ....---------------------------------.- .. 60
20 Location of the principal mines and plants in the Florida-Georgia
fuller's earth district _-------- --_-_________ -------- 65
21 The Floridin Company's Frank Smith No. 2 mine -_ -------.-- 66
22 Chesebrough mine of the Floridin Company .-------- 67
23 Index to reports on radioactivity surveys in Florida ----. -------- 75
24 Quarry of the Bradenton Stone Company, Manatee County -._ 82
25 Cutting "Travertine" at the Bradenton Stone Company, Manatee
County ------ -- ------------------------------ 83
26 Splitting "Travertine" at the Bradenton Stone Company, Manatee
County ..._-----__--__...---------- ---------..------.. 83
27 Dimensional stone quarry in the Key Largo limestone, Windleys
Key, Monroe County ---__ ------- --------.-- -- --- 84
28 Detailed view of Key Largo limestone at Keystone Art Company's
quarry on Windleys Key, Monroe County ---- ---- 84
29 Dolomite quarry of the Southern Dolomite Company, Palmetto,
Manatee County ______ ___ -------------------- -- 87





30 Live Oak Stone Company quarry, Live Oak, Suwannee County ----... 88
31 Lansing quarry, Florida Rock Products Corporation, Hernando
County ------------------------ 89
32 Coquina quarry in Anastasia formation, Anastasia Island, St. Johns
County __.------------------ 90
33 The Lehigh Portland Cement Company's Bunnell plant ------- 91
34 Smith Brothers' quarry, Brevard County _._____-.__-......------------- 92
35 Dredge of the All-Florida Sand Company, Unincorporated, Inter-
lachen, Putnam County __.... ------.------------------------ 95
Tables Page
1 Production and Value of Peat in Florida ...- --------------- 33
2 Production and Reserves of Phosphate Rock in Florida ------- 36
3 Production and Value of Phosphate Rock Mined in Florida from Be-
ginning of Mining in 1888 through 1956 __ ----------- --- 47
4 Mineral Industry in Florida 1942-1955 _--- -- --- --- facing 48
5 Consumption of Phosphate Rock Produced in Florida in 1954 by uses 49
6 Production and Value of Fuller's Earth 1940-1955 -------- 63
7 Apparent Consumption of Lime (Both Quicklime and Hydrated
Lime) Sold or Used in Florida --_..__..................---.........----------------- 71
8 Lightweight Aggregate Test Data from Selected Localities in Florida 79
9 Crushed Limestone Sold or Used by Producers 1945 through 1956 -__ 86
10 Quantity and Value of Sand and Gravel Produced in Florida 1945
through 1955 .---------....-------------------. 94
11 Movement of Sand and Gravel to Market by Method of Haulage --.. 95
12 Rock and Mineral Producers 1954 and 1955 ____ ----------- 102


























































Printed by E. O. Painter Printing Company, DeLand, Florida






ACKNOWLEDGMENTS


All statistical data, unless otherwise indicated, were obtained
from publications of the U. S. Bureau of Mines. The annual pub-
lication Minerals Yearbook contains a complete review of all min-
eral activity in the United States and the data for Florida are col-
lected under a cooperative agreement between the U. S. Bureau of
Mines and the Florida Geological Survey. That publication, to-
gether with the series Mineral Resources of the United States
which was formerly published annually by the U. S. Geological
Survey, contains the most complete source of information on the
growth and development of the mining industry in the United
States. The author's indebtedness to these sources of data is
here acknowledged.
In writing this report, no attempt was made to give credit to
all sources of data because many paragraphs would require ten or
more references. The publications of the Florida Geological Sur-
vey have been freely drawn upon without specific reference and
this use of material is gratefully acknowledged. Special credit is
due Dr. Herman Gunter, State Geologist, and to the members of
the Florida Geological Survey's staff who have aided in the prepa-
ration of this manuscript.










MINING AND MINERAL RESOURCES


JAMES L. CALVER

INTRODUCTION

GENERAL STATEMENT

In area, Florida ranks in size with Georgia, the largest state
in the southeastern United States. With 58,666 square miles of
land surface within its boundaries, the area of Florida is only
210 square miles less than that of the State of Georgia. Situated
wholly within the Coastal Plain Province, Florida is underlain by
4,000 feet or more of sedimentary rocks that overlie a basement
of older sedimentary, metamorphic and igneous rocks. By far the
greater portion of the State is covered by a surface mantle of soils
and sands that may reach 200 feet in thickness. This mantle ob-
scures the underlying sediments and rocks except where they are
exposed around its borders and in areas where the cover is thin
or absent as a result of erosion. The character of the sediments
can best be determined by the study of samples recovered from
borings, wells, test holes, and pits. It is, therefore, easy to under-
stand why the mineral resources of Florida have not been fully
explored or evaluated.
The development of the mineral industry in Florida, its con-
tinued growth and diversification, is dependent upon the utilization
of materials ordinarily classified as nonmetallic minerals. The fore-
most mineral products of the State are phosphate, limestone, sand
and gravel, fuller's earth, kaolin, cement, ilmenite, rutile, zircon,
petroleum and peat. These rock and mineral industries have ex-
perienced a tremendous increase in production in recent years and
the value at the mines and quarries for these products increased
more than 730 percent from 1940 to 1955. The value for 1940
production as reported to the U. S. Bureau of Mines was
$14,854,000, and for the 1955 production, $108,917,000. During
this 15-year period, Florida's rank in mineral production among
the states increased from thirty-fifth in 1940 to twenty-fourth in
1954, the last year for which comparable data are available. Ac-
cording to the 1954 census of mineral industries that was completed
by the U. S. Bureau of the Census, Florida ranks third among all
the states in the value of nonmetallic mineral mining. Only Cali-
fornia and Texas reported higher values for the production of non-





12 FLORIDA GEOLOGICAL SURVEY-BULLETIN THIRTY-NINE

metallic materials. The mining industry continued to expand dur-
ing 1956 with total mineral production estimated at $132,955,000
or 22 percent above 1955.
CONSERVATION PRACTICES
Conservation of ores and various mineral and rock materials
does not include the concept of hoarding. The only realistic defi-
nition of conservation, as applied to the mining industry, is effi-
cient production for prudent and beneficial use. While there is con-
cern about the continual drain and dwindling of mineral resources,
and wonder about what succeeding generations will do, such con-
cern and wonder is largely misplaced. Future needs will be met
through more efficient utilization, replacement by alternates, and
continuous discovery of new deposits. The conservation of soil by
the control of erosion and the conservation of forests by the pre-
vention of fires are entirely different concepts. The purpose is to
prevent waste, useless dissipation, and needless loss. Keeping ore
either in the ground or hoarding it above ground achieves none
of these objectives as long as the products of the mines are used
to good purpose by individual consumers.
There is a vital difference between the proved reserves and the
potential resources of any area, state, or nation. Without implying
that all of the outcropping mineral deposits have been found, at-
tention must be turned to the deposits that do not show on the
surface. It is the existence of such hidden deposits about which
some people are skeptical. Although hidden deposits can be proved
conclusively only by penetration of drills, a strong case for the
fact that these deposits do exist can be based on geologic science,
experience, and the history of mining districts. TWdoubt the exis-
tence of concealed deposits of great size and value is contrary to
the laws of probability and in areas in which geologic conditions
are distinctly favorable, it is unrealistic to doubt the existence of
deposits of tremendous importance.
Progress in the methods, techniques, and processes of mining
and of treating minerals and rock materials for recovery of usable
constituents make possible the working of progressively lower
grade and lower quality deposits. Accompanying the development
and use of more efficient methods, there is an expansion, in an
economic sense, of the total reserves, but even the most proficient
methods are of no avail unless deposits of usable materials have
been found. The hidden deposits do nothing to replenish supplies
unless they can be found and it is a challenge to the resourceful-
ness of geologists, geophysicists, geochemists, and mining




VALUE OF FLORIDA MINERAL INDUSTRY

ANNUAL TREND AND AVERAGE RATE OF INCREASE 2


TOTALLY
PmOSPHA.


in
0,


VALUE I I ,ILE OFi Ei L E I, r0," O ,.
TE VALUE LL ,lltaI L FODU '.,. TTi "4 I.,LLI:,r ,:
F',:, RMOICE ROC' K *5 0 MILL .r 80

70

O
zo












phosphate production increased to nearly $66 million. n





phosphate production increased to nearly $66 million. c




14 FLORIDA GEOLOGICAL SURVEY-BULLETIN THIRTY-NINE

engineers to find them. New techniques and methods, new mechani-
cal devices and electrical instruments all contribute to the search
for hidden deposits. The application of airborne radioactivity sur-
veys to make rapid low-cost reconnaissance of large areas in the
search of uranium and thorium ores is a relatively recent addition
to technique and methods that are at the disposal of geologists. The
development and use of geophysical methods to translate rock
structures thousands of feet underground has given the petroleum
industry a tool which has led to the discovery of tremendous quan-
tities of new oil. Unfortunately, the known techniques are not
universally effective and in some areas, including the State of
Florida, the interpretations of the data developed by known meth-
ods of geophysical investigation are inconclusive. Progressively
new methods and new electrical and mechanical instruments of
intricate design and extreme sensitivity will displace older ones.
Notwithstanding the fact that many problems encountered in the
search for mineral deposits are far different and more complex
than those associated with the search for promising oil structures,
the progress and success that has been achieved in the fields of
geochemistry, geophysics, and the varied branches of electronics
gives justification to the belief that problems involving the detec-
tion, measurement, and determination of composition of hidden ore
deposits are capable of solution. To doubt that this need will be
met is to underestimate the resourcefulness of scientists, tech-
nologists, and engineers.
The mining industry has come to the realization that proper
after-treatment and restoration of worked-out areas will be de-
manded by the general public. Proper land utilization requires
that the resources extracted from the earth be incorporated into
the economy as efficiently as possible. Urban encroachment on
usable deposits may result in the permanent withdrawal of those
materials from the economy of the community. In order to avoid
such waste, it is necessary that planning boards and other groups
that exercise supervision of industrial development give favorable
classification of such land for miningjauposes. In the Miami area
of Dade County, for example, the limestone producers, working in
cooperation with the zoning and planning boards, are developing
quarries according to definite plans and the site will be left in con-
dition suitable for residential development. In fact, real estate
values are enhanced and higher values will exist after completion
of the quarry operations than existed prior to mining.
An outstanding example of land use in an abandoned mining
area is found in the northern part of St. Johns County at Ponte





MINING AND MINERAL RESOURCES


Vedra. Following the termination of mining activities in 1929,
the area that had produced rutile, ilmenite, and other heavy min-
erals since 1916, was developed into residential property. Not only
are several hundred homes situated in the original mining area
but the Ponte Vedra Country Club and golf course are located on
the "mined-out" portion of the property.
All of the operating companies in the land-pebble phosphate
field are very conscious of the value of progressive land conserva-
tion and have programs for utilizing unmined land, as well as
realizing return from mined-out lands. Landownership by the
major companies totals more than 300,000 acres in Polk and Hills-
borough counties. Portions of both the prospected areas and the
mined-out areas are being operated as tree farms and pastures.
One company has over 40,000 acres under an intensive forestry
program and selective cuttings have been made on the slash pines
that were planted in 1939. New plantings by that company are
being made at the rate of one-half million trees per year, and a
total of more than 4 million trees have been planted. Other land-
use practices by the phosphate companies include the establish-
ment of recreational areas and the conversion of mined-out pitsv
into lakes that may be stocked with fish.
In 1956, one of the phosphate producing companies entered
into a large-scale land reclamation program that will extend over
a five-year period. During the project, a tract consisting of 700
acres located on the south side of Lakeland will be reclaimed for
residential use. As in the example of land reclamation completed
in 1942 at Ponte Vedra, and that under way in the Miami area,
the development of enhanced surface values of real estate is being
accomplished with the cooperation of planning groups and the
mining companies.

THE HEAVY MINERAL INDUSTRY
REVIEW OF DEVELOPMENT
The first heavy mineral mining development in Florida was lo-
cated at Ponte Vedra, then known as Mineral City, St. Johns
County, where production began in 1916 to supply ilmenite for
titanium tetrachloride manufacture. This fuming liquid was used
during the first World War in smoke screens, tracer bullets, and
spotting shells. The original company, Buckman and Pritchard,
Incorporated, operated under the name of the discoverers and de-
velopers of the deposit, Henry H. Buckman and George A. Prit-
chard. After 1922, the company became a subsidiary of the Na-
tional Lead Company. At first only ilmenite was recovered from





16 FLORIDA GEOLOGICAL SURVEY-BULLETIN THIRTY-NINE

the heavy mineral concentrate but later when uses for zircon and
rutile became known, these minerals were also recovered. The
first commercial production of zircon was reported in 1922 and
that of rutile in 1925. Production from this mining venture
reached a peak in 1927 but was discontinued entirely in 1929. De-
pletion of the best ore and availability of cheaper ores from India
and Australia led to the termination of the mining activities. The
subsidiary, renamed the Ponte Vedra Company, developed the
property residentially and sold it in 1942. Ponte Vedra Beach,
with several hundred homes, is situated on the original mining
area and the country club and golf course are located on the
"mined-out" portion of the Buckman and Pritchard property.
There were no companies producing heavy minerals in Florida
from 1929 to 1939 but in 1940 a small quantity of ilmenite, rutile,
and zircon was produced by the Riz Mineral Company, from natu-
ral concentrates found in the beach sands near Melbourne, Brevard
County. This company separated ilmenite, rutile, zircon, and mona-
zite from ores selectively mined on the ocean beaches in the
vicinity of Melbourne, and later from a dune area situated near
Vero Beach, Indian River County. The mineral separation plant,
located at Palm Bay, was several miles from all of these deposits
and the concentrate was trucked to the plant for processing. Pro-
duction was more or less continuous until the fall of 1946 and inter-
mittent until 1948 when the company was sold and reorganized as
the Florida Ore Processing Company, Incorporated. That company
made improvements in the Palm Bay mineral separation plant and
five products were sold: ilmenite, rutile, zircon, garnet, and mona-
zite.
By arrangement with Hobart Brothers, Incorporated, Troy,
Ohio, manufacturers of welding rods, a mining company was or-
ganized under the name Florida Minerals Company to dredge and
concentrate the heavy minerals from dune deposits situated im-
mediately south of Vero Beach, Indian River County. All of the
concentrate produced by this company's operations was trucked to
the Palm Bay plant in Brevard County. Florida Minerals Company
later developed a deposit in a dune area situated west of Winter
Beach, Indian River County and used a suction dredge to mine
and a concentration plantto remove the quartz sands from the
heavy mineral grains. This concentration depends upon the specific
gravity differences between the heavy mineral grains and the
quartz grains and is accomplished by the use of a restricted trough
through which a slurry of mineral sands, and water is directed. As









z
s
5
'2


IXL
3~~
a


-^ "


Figure 3
Dredge and heavy mineral concentration barge, Florida Minerals Company, Winter
Beach, Indian River County.





18 FLORIDA GEOLOGICAL SURVEY-BULLETIN THIRTY-NINE

the trough narrows and deepens, the minerals heavier than quartz
tend to settle and the discharge from the lower end of the trough is
split to recover the heavy concentrate. Because the troughs are ar-
ranged in a circle and the pipes that feed the slurry to the troughs
have the appearance of ribs, this concentrator is named an inverted
umbrella concentrator. In March 1955, the Florida Ore Processing
Company discontinued its mining activity and processed the heavy
mineral concentrate supplied by Florida Minerals Company. On
October 17, 1955, the Palm Bay mineral separation plant was de-
stroyed by fire. A new processing plant, built by Hobart Brothers,
Incorporated, was constructed near the Winter Beach mine and full
scale operation began in February 1956. The products recovered
are ilmenite, rutile, zircon, garnet, and monazite.
In August 1943, the Rutile Mining Company of Florida, a sub-
sidiary of the National Lead Company, started to mine and re-
cover ilmenite and rutile from sand dunes on a 500-acre tract
situated in Duval County midway between Jacksonville and the
Atlantic Coast. Operating under a lease from the Rutile Mining
Company of Florida, the Humphreys Gold Corporation moved its
entire plant and equipment from Coos County, Oregon to Florida
and began operations in Florida on April 1, 1944. The concentra-
tion plant was designed to treat 8,000 tons of sand per 20-hour
day and the quality of the ore averages between four and five
percent heavy mineral. The heavy mineral concentrate has the
following assemblage of minerals:

Titanium minerals:
Ilmenite 40 %
Leucoxene (altered ilmenite) 4 %
Rutile 7 %
Zircon 11 %
Monazite 0.5%
Kyanite, Sillimanite, Staurolite and others 37.5%
100.0%

From that quantity of ore, approximately 2,000 tons of ilmenite
and 300 tons of rutile were separated per month. In 1946, pro-
duction of zircon was begun and the tailings from the ilmenite-
rutile dry separation plant, which were stored for that purpose,
were reworked. Zircon production, about 1,000 tons per month,
required installation of additional spirals and a second dry sepa-
ration plant using electromagnetic and high-tension separators. In
1949, the production of monazite, about 20 tons per month, was
added to the plant's output. The profitable production of these
minerals over a period of 12 years was made possible principally





MINING AND MINERAL RESOURCES


by use of the Humphreys spiral concentrator which replaced flo-
tation cells and shaking tables in the beneficiation of the ores. The
current development is under the joint ownership of the National
Lead Company, Titanium Division, and the Rutile Mining Com-
pany of Florida. The output from this mine and plant, supple-
mented by imports from Australia, provided an adequate supply
of rutile during the war years for coating the welding rods which
were essential to the tremendous shipbuilding and armament pro-
gram of the United States during World War II. Production from
the Jacksonville plant has been continuous since it began operation.
The U. S. Bureau of Mines, working in cooperation with the
Florida, Geological Survey, conducted a drilling program in Florida
during 1947 to establish reserves of titanium minerals. This study
outlined an ore body of considerable size situated in the western
portions of Clay and Duval counties. This deposit, located in Trail
Ridge, occupies only a small portion of the entire ridge and the
ridge constitutes a relatively minor portion of the Central High-
lands area of the Florida Peninsula. Where mined, the sand
averages about four percent heavy mineral grains, the remainder
being quartz. The mineral composition of the heavy portion of
the sand varies from place to place but includes the following as-
semblage with which a typical analysis is listed.

Titanium minerals -- 45%
Zircon . ..------- ------------ -- ___ .. 15%
Staurolite ------_ 20%
Sillimanite -------- 5%
Tourmaline _-- ------ 5%
Kyanite _---------. ____ 4%
Andalusite, pyroxene, spinel, and
corundum ---------- ---- __-- __ __ 6%

The ore zone ranges in thickness from 35 to 60 feet, and no
overburden is removed as the ore lies at the surface. The deposit
rests on a five-foot layer of trees and other organic material below
which is coarse sand that is barren of heavy minerals. The ore
zone includes a "hardpan" that occurs at varying depths and
thicknesses below the surface. It consists of masses of sand ce-
mented with a tar-like substance, a product of decomposition of
vegetable growth. The hardpan approaches the hardness of or-
dinary sandstone.
In December 1947, E. I. du Pont de Nemours & Company, In-
corporated, entered into a long-term agreement with the State
Armory Board to mine the titanium-bearing property situated on
Trail Ridge within the boundary of Camp Blanding, Clay County.
The Humphreys Gold Corporation, under contract with Du Pont,






20 FLORIDA GEOLOGICAL SURVEY-BULLETIN THIRTY-NINE



CONCENTRATION OF HEAVY MINERALS
YEARLY FEED FROM DREDGE 8,000,000 TONC ,4 3% HEAVY MINERAL
IN MILLIONS OF TONS
46 78


350,000 TONS HAV
80% MINERALS GREAT
THAN 2 7 Sp Gr




k


HUMPHREYS SPIRALS CLASSIFY SAND
GRAINS ACCORDING TO SPECIFIC GRAVITY
ING 7,650,000 TONS DISCARDED TO BACKFILL
TER 99 3% MINERALS LESS
THAN 27 SpGr (MAINLY QUARTZ)




SEPARATION OF HEAVY CONCENTRATE
YEARLY CAPACITY- 350,000 TONS


APPROXIMATE ANALYSIS

24% 105% 15.5% 9% 21% 20%
ILMENITE TITANIUM STAUROLITE ZRCON SILLIMANITE QUARTZ
MINERAL KYANITE
TOURMALINE ETC.

HIGH TENSION SEPARATION

ELECTRICAL CONDUCTORS ELECTRICAL NON-CONDUCTORS






MAGNETIC SEPARATION MAGNETIC SEPARATION
I NON-
MAGNETIC MAGNETIC MAGNETIC NON-MAGNETIC
TITANIUM 4% M
ILMENITE MNERAL STAUROLITE

63%Ti02 60%TiOz +45%Al,10O

ZIRCON CONCENTRATION 8 SEPARATION
Sp. Gr. CLASSIFICATION-HUMPHREYS SPIRALS
ZIRCON OTHER MINERALS
SpGr468 Sp.Gr 3.2-4.2 Sp Gr 2.65
90% ANITE CORUNDUM i QUARTZ
ZIRCON ANDALUSITE ETC
PYROXENE TO STORAGE PILE


HIGH TENSION SEPARATION

NON-
CONDUCTORS CONDUCTORS
MAINLY TITANIUM MINERALS
TO STORAGE PILE


MAGNETIC SEPARATION


NON-
MAGNETIC MAGNET
ZIRCON
98%
ZrSIO


MAINLY STAJROLITE
AND TOURMALINE
TO STORAGE PILE


Figure 4
Schematic flow-sheet of the Trail Ridge heavy mineral mine and
mineral separation plant.


\




MINING AND MINERAL RESOURCES


built the Trail Ridge mineral concentration and separation plant
which has a capacity to treat 20,000 tons of sand per day. The
mining and processing is contracted by the Humphreys Gold Corpo-
ration and production from the plant began in April 1949. The
titanium mineral produced consists of a weathered ilmenite that
analyzes about 63 percent TiO, and a residue of altered titanium-
bearing minerals, largely leucoxene, that contains about 80 per-
cent TiO,.
The recovery of staurolite from the tailings of the titanium
mineral dry plant was begun in the summer of 1952. This by-
product analyzes more than 45 percent Al2O0 and is used by the
Lehigh Portland Cement Company as a source of alumina in the
manufacture of portland cement at its Bunnell plant. A small
quantity of the product is also used in sandblasting. In addition to
staurolite, this product contains a small percentage of tourmaline,
zircon, ilmenite, quartz, and other minerals. Zircon is recovered
from the tailings that remain after the staurolite has been re-
moved. Concentrations of this mineral are made by taking ad-
vantage of the specific gravity difference between zircon (sp. gr.
4.68) and the associated minerals, sillimanite, kyanite, andalusite,
pyroxene, spinel, and others having specific gravities ranging from
3.2 to 4.2. The plant operated by the Humphreys Gold Corporation
at the Trail Ridge mine has a capacity of 2,500 short tons per
month. The mineral zircon is used for foundry sand, refractory
uses, ceramic uses, sandblasting, and as the ore from which zir-
conium and hafnium are recovered. The tailings of the mineral
separation plant are stockpiled for future recovery of sillimanite,
kyanite, and possibly other minerals when methods are developed
for their separation.
The second heavy mineral mine and plant to be located on Trail
Ridge was developed by the Du Pont Company and placed in oper-
ation in April 1955. The Highland plant is almost a duplicate of
the Trail Ridge plant and is likewise operated by Humphreys Gold
Corporation. Each plant has a designed yearly capacity of 100,000
tons of titanium minerals consisting of ilmenite and titanium min-
eral residue (mainly leucoxene, altered ilmenite, and rutile). At
the Highland plant, the heavy mineral tails from the titanium min-
eral separation plant are stockpiled for possible future recovery
of zircon, staurolite, sillimanite, kyanite, and possibly other min-
erals. Here, as at the Trail Ridge mine, monazite occurs in in-
sufficient quantities to warrant separation.





22 FLORIDA GEOLOGICAL SURVEY-BULLETIN THIRTY-NINE


DREDGE FEED
(4.3% HEAVY MINERAL )
I


TAILING CONCENTRATE MIDDLING TAILING CONCENTRATE IDDLING PO UNDERSIZE
TO BACKFILL I If 1- TO BACKFILL I- I I _

BIN AND PUMP IN AND PUMP

160 5-TURN SPIRALS 160 5-TURN SPIRALS

TAILING CONCENTRATE MID TAILING CONCENTRATE MIDDLING


BIN AND PUMP BIN AND PUMP

80 3-TURN SPIRALS 80 3-TURN SPIRALS

CONCENTRATE MIDDLING TRAT MIDDLING
TRANSFER
BIN AND PUMP

FINISHED CONCENTRATE
(80B HEAVY MINERAL) ,
BIN AND PUMP
I ELEVATOR ELEVATOR
BOOSTER PUMP
AND PIPE LINE 7 HIGH TENSION 4 HIGH TENSION
SEPARATORS SEPARATORS

CLASSIFIER MIDDLING NON-CONDUCTORS MIDDLING NON-CONDUCTORS
CONDUGITORS CONDUCTOR
OVERFLOW TO STORAGE
RECOVERY SUMP SAND STOCK PILE
OVERFLOW CAUSTIC ZIRCON
TO POND STORAGE T TOURMLITE
3 R KYANITE
.W ATR 3 HIGH TENSION KTANITE
SEPARATORS SILLIMANITE
I CONDITIONER I R
NON-CONDUCTORS MIDDLING ELEVATOR
C2 CONDITIONER CONDUCTORS MAGNETIC
I WATER SEPARATORS
I WASH TANK ELEVATOR
MAGNETIC NON-MAGNETIC
LASSER4 MAGNETIC STAUROLITE ZIRCON
I SEPARATORS PRODUCT MILL FEED
OVERFLOW SANDTO STOCK (45%Ala03)
TOf PI TN DRAIN NON-MAGNETIC MAGNETIC TO BIN FOR
GLAM SHELL RESIO ILMENITE SHIPMENT
EXAUST CIS-1 (63%TiO0)
GASES ELEVATOR TO BIN FOR
GASES ORE BIN SHIPMENT
CYCLONE SCREEN
SAND OIL FIRED DRYER 22F. OVERSIZE I
STO WASTE UNDERSIZE

SHAKER CONVEYOR 4 HIGH TENSION
AND SCREEN SEPARATORS

TRASH TO UNDERSIZE CONDUCTORS
WASTE- CONDUCTORS
FINISHED RESIDUE
(80% Ti 0)
TO BIN FOR
SHIPMENT

Figure 5
Generalized flow-sheet of Trail Ridge mine and plant.





MINING AND MINERAL RESOURCES


MONAZITE
Monazite is one of the by-product minerals that is recovered
in the processing concentrates of heavy mineral sands that con-
tain ilmenite, rutile, zircon, and other valuable minerals. Monazite
[(Ce, Y, La, Th) P04] is a phosphate of rare-earth elements that
contains up to 12 percent thorium oxide and one percent uranium
oxide. Both the thorium and uranium content of this mineral
may be recovered as a by-product in the extraction of the rare-
earth elements from the monazite. The rare-earth family of ele-
ments is composed of 15 metals that have closely related proper-
ties. These elements are neither rare nor earths but only within
the past few years has technology advanced sufficiently to produce
these elements in quantities sufficient for research. The group of
elements were called "earths" because their oxides resemble the
oxides of the family of alkaline-earth metals (barium, calcium,
and strontium) and "rare" because they were thought to be scarce.
In the heavy mineral sands of Florida, monazite occurs as small,
round, glassy grains that have a yellowish-brown color; the min-
eral has a hardness of 5 to 5.5 and a specific gravity of 4.6 to 5.3.
It is the chief ore mineral from which thorium is recovered and






















Figure 6
Suction dredge at Trail Ridge mine, Clay County. The ore zone is about 60
feet thick and, as shown in the photograph, about 15 feet of the deposit extends
above water level. F. S. N. B. photograph.





24 FLORIDA GEOLOGICAL SURVEY-BULLETIN THIRTY-NINE


Figure 7
Floating concentration plant at the Trail Ridge mine in which the ore con-
taining approximately four percent heavy mineral is beneficiated to eighty
percent heavy mineral by use of Humphreys spiral concentrators.
F. S. N. B. photograph.


.. .... .....


Figure 8
Back-fill or mined-out area at Trail Ridge heavy mineral mine, Clay County.
F. S. N. B. photograph.





MINING AND MINERAL RESOURCES


this element is distributed in the crust of the earth in quantities
only a little less than lead and about three times as abundant as
uranium.
Cerium is the most important rare-earth element produced
from monazite and the principal commercial product made from
it is misch metal. This metal contains about 40 to 55 percent
cerium; 22 to 30 percent lanthanum; 15 to 17 percent neodynium;
8 to 10 percent prasedynium, yttrium, samarium, and other rare-
earth elements. When alloyed with iron, the product is used as
sparking flints for cigarette lighters, miners' lamps, and acetylene
welding torches. Approximately one-quarter of the rare-earth
metals is consumed in misch metal and ferrocerium; one-half of
the production is used in carbon arc electrode cores, and the re-
maining one-quarter in miscellaneous uses including glass and
metal polishing compounds, waterproofing, mildew-proofing, and
glass manufacture. Cerium oxide is an excellent abrasive material
and is used in polishing both metal and glass surfaces.
Although thorium is found in at least 100 minerals, almost all
of the thorium of commerce is obtained from monazite. The chief
uses of thorium and its compounds are in the manufacture of gas
mantles, refractories, and polishing compounds, and in the prepa-
ration of various chemical and medical supplies. Of potential im-
portance in the field of atomic energy, is the fact that thorium-
232, when subjected to bombardment by neutrons, is converted into
uranium-233, in an amount exceeding the quantity of uranium-
233, uranium-235, or plutonium-239, that is consumed in pro-
viding the necessary neutrons for the conversion. It is this cre-
ation of an excess of nuclear fuel that is known as "breeding." It
is reasonable to assume that when the utilization of thorium as a
fissionable material develops, demand for the metal will be equal
to that for uranium.
The thoria content of monazite varies considerably with lo-
cality. The material recovered from the heavy mineral sands of
Florida contains about five percent thoria. The average of five
analyses of monazite, samples of which were recovered from the
heavy mineral sands located on Amelia Island, St. George Inlet,
Mayport, Ponte Vedra, and Anastasia Island, gives a Th02 con-
tent of 4.96 percent and a UOs content of 0.55 percent.
ZIRCON
The mineral zircon is a silicate of zirconium and is composed,
theoretically of 67.2 percent zirconia and 32.8 percent silica. This
composition is expressed in the formula ZrSiO4. Contrary to the




26 FLORIDA GEOLOGICAL SURVEY-BULLETIN THIRTY-NINE

common belief that zircon is a rare mineral is the fact that it is
widely distributed in all types of rocks and sediments and zir-
conium is more plentiful in the crust of the earth than nickel,
copper, zinc, or lead. Zircon is a constituent of practically all
stream and beach sands; however, it occurs in rather small quan-
tities in most deposits. In many instances it can be detected only
through careful chemical and microscopic examination. The spe-
cific gravity of zircon (4.68) is much higher than that of quartz
(2.65), and the mineral commonly occurs with the heavy mineral
sands found associated with beach deposits. In Florida, zircon
is a constituent of the heavy mineral sands and it is recovered in
the mineral separation plants after the titanium minerals, il-
menite and rutile, have been removed from the concentrate of
heavy minerals.
Almost the entire zircon production for the United States for
every year from 1944 through 1949 may be accounted for by the
output from the South Jacksonville plant of the Rutile Mining
Company of Florida, which is operated by the Humphreys Gold
Corporation. During these years, a small portion of the total zircon
production was reported by the Florida Ore Processing Company
located near Melbourne. Early in 1949, the titanium mineral plant
of the E. I. du Pont de Nemours & Company, located near Starke,
began operations and in 1950 large quantities of zircon were being
produced by this plant. The total quantity of zircon produced
annually from these mining operations has placed the United
States in a position of self-sufficiency with respect to zircon.
The production of zircon in 1953 amounted to 21,234 short tons,
dropping to 17,959 short tons in 1954 and in 1955 rose to 28,913
short tons. This favorable situation came about only incidentally
through the exploitation of the heavy mineral sand deposits of
Florida for their titanium mineral content.
According to data published by the U. S. Bureau of Mines
Minerals Yearbook 1950, from 20,000 to 30,000 tons of zircon
are consumed annually in the United States. Zircon and the pre-
pared oxide of zirconium, zirconia, are extensively employed in
the ceramic industry in the manufacture of porcelains and glazes.
The use of zirconia as an opacifier in enamels, once an important
use, has been largely discontinued and replaced by titanium dioxide.
Ground zircon finds use in the form of bricks, cements, and molded
shapes, as a refractory material capable of withstanding very high
operating temperatures. Zircon refractories are used in foundries
and in furnaces for melting glass and aluminum. Zircon sand is
replacing quartz sand in foundry practice for gray iron, steel,






MINING AND MINERAL RESOURCES


ZIRCON
MILL FEED

IN AND PUMP

32 5-TURN SPIRALS

TAILING MIDDLING
STORAGE PILE
KYANITE ZIRCON
SILLIMANITE CONCENTRATE
TOURMALINE
ANDALUSITE BIN AND PUMP
PYROXENE
QUARTZ
32 3-TURN SPIRALS

ZIRCON TAILING
CONCENTRATE

S32 3-TURN SPIRALS
I I
ZIRCON TAILING
CONCENTRATE


CLASSIFIER

SLIME SOLIDS TO
TO WASTE OIL FIRED KILN
1200 F.
90% ZIRCON

ELEVATOR

2 HIGH TENSION
SEPARATORS

CONDUCTORS MIDDLING
STORAGE PILE

NON-CONDUCTORS

ELEVATORS

2 HIGH TENSION
SEPARATORS

CONDUCTORS MIDDLING
STORAGE PILE

NON-CONDUCTORS

ELEVATOR

4 MAGNETIC
SEPARATORS
I I
MAGNETIC NON-MAGNETIC
STORAGE PILE I
FINISHED PRODUCT
98% ZIRCON
TO BIN FOR
SHIPMENT


28 5-TURN SPIRALS

TAILING MIDDLING
STORAGE PILE
CONCENTRATE
I


Figure 9
Generalized flow-sheet of the Humphreys Gold Corpora-
tion's zircon recovery plant at the Trail Ridge mine, Clay
County.


~




28 FLORIDA GEOLOGICAL SURVEY-BULLETIN THIRTY-NINE

bronze and light metal castings. The thermal conductivity of zir-
con is much higher than that of quartz and the more rapid chilling
results in superior castings that require a minimum of buffing and
grinding. The molten metal does not wet the zircon, and foundry
sand and molding sands made from zircon do not adhere to the
outer surface of the castings. Zircon is the highest temperature
refractory in common use that can be produced in bulk. It is pre-
ferred over other super-duty refractories because there is no pene-
tration of the brick by metal, it has a low coefficient of expansion,
and high resistance to corrosion and to mechanical abuse occurring
in the course of charging and cleaning the furnace. Certain com-
pounds of zirconium possess such high refractory characteristics
as to allow their use in the stationary parts of combustion cham-
bers of gas-turbine and jet engines. Commercial applications of
zirconium compounds include chemical catalysts, textile water re-
pellents, and tanning agents.
The metal zirconium has found use in powder form for flash-
light powders, flares, fireworks, and detonators. The metal is also
used in various radio and electronic tubes to absorb gases within
the tube. Zirconium is essential in making certain special steels
and in alloys of magnesium for airplane construction. One of the
most interesting properties of the metal zirconium is its great af-
finity for various gases, such as oxygen, nitrogen, carbon mon-
oxide, carbon dioxide, hydrogen and water vapor. Considerable
quantities of these gases can be absorbed by zirconium at high
temperatures and retained permanently in the metal. This property
of acting as a "gas sponge" makes zirconium particularly valuable
as a "getter" in the manufacture of high vacuum radio and elec-
tronic tubes. The excellent strength of the metal, coupled with
its corrosion resistance and extremely low neutron absorption
characteristics indicate that increasing quantities of zirconium will
be utilized as a structural material in atomic power reactors. In-
asmuch as uranium atoms are split by neutrons, any absorption of
the neutrons by the structural material of the reactor, or atomic
engine, would lower the efficiency of the reactor.
Hafnium: Almost all zircon contains one to three percent haf-
nium, an element that has such similar chemical properties to the
element zirconium that their separation is difficult. In order to
produce pure zirconium and hafnium metal, zircon must undergo
a complicated and expensive chemical process. The metal hafnium
has properties opposite to zirconium with respect to neutron ab-
sorption and is used to make control rods for nuclear reactors.
Hafnium, discovered in 1923, is a metallic element that is




MINING AND MINERAL RESOURCES


ductile, is highly resistant to corrosion, and has a very high absorp-
tion cross section for neutrons. The hafnium content of the earth's
crust has been estimated to be greater than mercury and silver,
and just as plentiful as beryllium and uranium.
TITANIUM MINERALS (ILMENITE AND RUTILE)
Titanium is a metallic element and is the ninth most common
element in the earth's crust. It is more abundant than all of the
lead, zinc, tin, antimony, nickel, copper, gold, and silver combined
and occurs as a minor constituent or impurity in many ores and
minerals. Only in ilmenite, rutile, and related materials does ti-
tanium occur in sufficient abundance to be commercially useful.
Ilmenite (FeTiOs) is a black, tabular mineral with a metallic luster.
Ideally, it contains 36.8 percent iron, 31.6 percent titanium, and
31.6 percent oxygen, although the iron-titanium ratio may vary
considerably. The mineral is magnetic and becomes more strongly
magnetic after heating. Rutile (Ti02) is a reddish-brown to black
prismatic mineral with an adamantine luster and a pale brown
streak. It is composed of 60 percent titanium and 40 percent oxy-
gen but some iron is usually present. Both of these titanium min-
erals, together with altered ilmenite and leucoxene, are recovered
as sand grains from the heavy mineral portion of the sands of
Florida.
By far the largest use for ilmenite is in the manufacture of
titanium dioxide pigment. Its whiteness, spreading quality, chemi-
cal stability, and cheapness, make it the most popular white pig-
ment. It has a high index of refraction and remarkable opacity
or hiding power that is made use of in pigments for paints, paper,
rubber, enamels, coated fabrics, floor coverings and many other,
products. Rutile and rutile-ilmenite mixtures are used for coating
electric welding rods. This is the largest use for rutile, and its
function is to shield the arc from oxidation during welding and to
produce a slag which protects the cooling weld.
The production of titanium metal from rutile and from altered
ilmenite has received a great deal of publicity during recent years
naming titanium the "miracle metal," the "wonder metal," and the
"Cinderella metal." Production of titanium sponge metal in the
United States has increased from 10 tons in 1948 to about 7,400
tons in 1955, and the titanium metal expansion program calls for
an annual output of 21,600 short tons in 1957. The shortage of
titanium metal is the result of metallurgical obstacles and not to
scarcity of titanium minerals. Titanium minerals are reduced to
metal with great difficulty because of the characteristic of titanium





30 FLORIDA GEOLOGICAL SURVEY-BULLETIN THIRTY-NINE

to hold to or combine with oxygen. Titanium base alloys are as
strong as structural steel alloys but weigh only one-half as much
as steel; they retain their strength at elevated temperatures where
other structural metals lose strength, and they also possess great
resistance to corrosion.
GARNET
The name "garnet" is given to a group of seven minerals, all
of which are silicates of aluminum, calcium, and iron. The most
common garnets are almandite and andradite which are dark red
to reddish-brown in color. Some of the material that is recovered
from the heavy mineral sands of Brevard and Indian River coun-
ties, Florida, is pink in color and is the variety called rhodolite. All
of the Florida production is utilized in the abrasive industry for
sandblasting in monument works and in cleaning the carbon from
spark plugs. The production of garnet in Florida is strictly a by-
product of the heavy mineral industry.
STAUROLITE

Staurolite is an iron aluminum silicate that contains ideally
15.8 percent FeO, 55.9 percent A120O, 26.3 percent Si02 and 2 per-
cent HO. The mineral was first recovered at the Trail Ridge heavy
mineral separation plant in sufficient quantities to be an industrial
mineral. Although staurolite was first used for a sandblasting ma-
terial, the first important industrial use is in the manufacture of
portland cement where it substitutes for clay in supplying the
necessary alumina and also contributes to the iron content as re-
quired by the cement formula. Current production from the Trail
Ridge plant where the heavy mineral fraction contains 14 percent
staurolite, is estimated at 20,000 short tons annually.
KYANITE AND SILLIMANITE
Modern technology in many industrial processes demand ever
increasing high temperatures and superior refractory materials
are continually in demand. Requirements for refractory materials
are most exacting when high temperatures are required, or sudden
changes in temperature are encountered, or when contact with
molten metals and slags are necessary. The refractories used for
these high temperature applications are identified commercially as
mullite, kyanite, or sillimanite. Prior to World War II, most of
the kyanite-mullite refractories were made from kyanite imported
from India. Since that time, synthetic mullite, made from bauxite
and various alumina-silica mixtures, have been used commercially.





MINING AND MINERAL RESOURCES


Kyanite and sillimanite are aluminum silicates (A120sSi02)
which when heated are transformed to mullite (3A1208.2Si02).
Kyanite exhibits considerable expansion when heated between
2,2000F and 2,4000F and is converted to mullite and glass at
2,4500F. Because of its expansion characteristic, kyanite ore is
calcined prior to its use. Sillimanite conversion to mullite is ac-
complished without volume change, but the mineral does not occur
in quantities large enough to be mined. Kyanite and mullite pro-
duced from kyanite are on the United States list of strategic min-
erals.
Both kyanite and sillimanite occur in sand-size grains in the
tailings from the heavy mineral separation plants. Recent studies
conducted by the U. S. Bureau of Mines show that both of these
minerals can be separated and recovered. Also, tests have shown
that the kyanite-sillimanite mixture has a pyrometric cone equiva-
lent of cone 38 (about 1,8350C) whereas the pyrometric cone
equivalent of commercial kyanite ranges from cone 36 to cone 37
(about 1,8150C). The fine-grained material is suitable for making
special shapes, porcelains, and clay-mullite mixtures. Refractory
bricks require coarser material but with nodulation it may be pos-
sible to produce a satisfactory product.

PEAT

Peat production in Florida established a new record in 1955
totaling 61,098 tons valued at $231,829. Within the past ten years,
production and value of this commodity has increased nearly four
times. During the same period, the production of peat in the
United States increased about two and one-half times. The sub-
stantial increase in demand for peat is attributed to the expanding
markets in the agricultural and horticultural fields. Peat is ex-
tremely varied in nature and composition and varies widely in
chemical and physical characteristics. In commercial usage three
types are recognized in accordance with established marketing
terminology: moss peat, which consists of poorly decomposed re-
mains of sphagnum and other mosses; reed or sedge peat, which
is formed from poorly or moderately decomposed plants of the
sedge family, reeds, cattails, and other swamp plants; and humus,
a term used to designate peats which are decomposed to the extent
that their biological identity is lost. Muck is referred to a "mis-
cellaneous" classification of peat if it is composed of 75 percent
peat on a dry basis-usually muck does not meet this requirement
for classification as a peat. Most of the peat produced in Florida




32 FLORIDA GEOLOGICAL SURVEY-BULLETIN THIRTY-NINE





















Figure 10
Mining and loading peat at deposit located near Florahome, Putnam
County.


is classified by the producing companies as humus. No general
agreement exists on the classification of peats according to their
biological characteristics and no standards have been developed for
classifying peat into fuel grades. For specific details of individual
deposits, reference should be made to The Peat Deposits of Florida,
Florida Geological Survey Bulletin No. 30.
The principal use for peat is as a soil conditioner and large
amounts are used for lawns, golf courses, in nurseries and in green-
houses. Although peat has a relatively high nitrogen content, it is
not readily available as plant food like the "soluble nitrogen" of
artificial fertilizer. The benefits derived from the use of peat re-
sult largely from improved physical conditions in the soil medium.
Another factor in its use as a soil conditioner is its ability to re-
tain moisture. Nearly all of the peat produced in the State is
marketed or used in soil improvement. Minor quantities of peat
are used as a filler in mixed fertilizers, packing material for plants
and vegetables, and as poultry litter. In its use as a filler in mixed
fertilizers, peat acts as a carrier for primary plant nutrients-
nitrogen, phosphorus, and potash-and not as an agent for sup-
plying plant food.





MINING AND MINERAL RESOURCES


The known original reserves of peat in Florida are recorded on
an air-dried basis as 2 billion short tons, see U. S. Geological Sur-
vey Circular 293, 1953. This quantity represents 14 percent of the
entire peat reserves for the United States. For many years Florida
has ranked among the foremost peat producing states and in 1955
reported the highest production with 22 percent of the total for
the entire United States. During that year, Washington ranked
second and Michigan third in the quantity produced.

Table 1
Production and Value of Peat in Florida
Year Short Tons Value
1942 2,400 $ 12,600
1943 7,316 16,950
1944 3,100 30,000
1945 15,194 66,747
1946 19,979 81,832
1947 42,300 126,000
1948 24,750 56,171
1949 11,800 69,000
1950 23,022 151,000
1951 25,748 161,000
1952 23,729 154,164
1953 27,678 185,524
1954 37,449 168,004
1955 61,098 231,829
1956 Est. 65,000 260,000
Data-U. S. Bureau of Mines

PETROLEUM

The discovery well of the Sunniland Oil Field, Collier County,
was brought in September 26, 1943, and produced 20,550 barrels
of 20.80 API gravity oil before it was converted into a salt water
disposal well on May 10, 1946. The discovery well was drilled by
the Humble Oil and Refining Company, and that company further
explored the region in the vicinity of Sunniland and developed a
small field that consists of 12 field wells. Figure 11 illustrates the
production record of the field. In January 1950 at the completion of
the last field well, there were 12 producing wells, seven of which
were flowing. By the end of that year, however, there was only one
flowing well. The field produced nearly 50,000 barrels a month
during 1951, and production has decreased slowly to an average of
40,000 barrels per month during 1956. Figure 12 is a photograph
of a rework derrick and oil well pump at the Sunniland field. Total
cumulative production of the field through 1956 is recorded at
4,797,721 barrels.




34 FLORIDA GEOLOGICAL SURVEY-BULLETIN THIRTY-NINE

The discovery well of the Forty-Mile Bend field, Dade County,
was completed February 6, 1954, and a field well, about three miles
east of the discovery well, was completed April 5, 1954. These wells
had initial daily production of 76 barrels and 112 barrels respec-
tively. The production record from these wells was disappointing
and the field was abandoned in September 1955. A total of 32,888
barrels of oil is recorded as the entire production.
Both in the Sunniland and the Forty-Mile Bend fields, the pro-
ducing zone is a porous limestone, named the Sunniland, that occurs
in the section of Lower Cretaceous rocks. This zone was found at
a depth of about 11,500 feet at Sunniland and about 11,300 feet
at Forty-Mile Bend.
During the 17-year period from January 1, 1940 through De-
cember 1956, 270 wells were drilled for oil and gas in Florida and
only 15 of these were completed as producers. When it is remem-
bered that there are 58,666 square miles of land surface within
the boundaries of Florida, a density of one well per 217 square
miles can only indicate the truly exploratory nature of the drilling
to date. The entire State remains a potential area for future dis-
covery and no portion of the State has been eliminated from the!
classification of a potential producing area.

PHOSPHATE ROCK
GENERAL STATEMENT AND RESERVES
For nearly half a century, the Florida deposits of phosphate
rock have supplied much more phosphate than all of the other
domestic deposits combined. Phosphate rock is constant neither
in composition nor occurrence and consists of a variable mixture
of calcium phosphates and other minerals. X-ray studies have
shown that the dominant phosphatic mineral in the Florida deposits
is fluor-apatite and this mineral is found in the extensive bedded
deposits of marine origin, in the residual or detrital deposits, and
in the replacements of limestone. Recent studies by the U. S. Geo-
logical Survey show that the uranium-bearing phosphorites of the
Bone Valley formation and of the Hawthorn formation are of
marine origin. The hard-rock phosphate deposits, on the other
hand, were formed by weathering of surface rocks, and deposition
of the phosphate as replacements of limestone. Such deposits are
not of marine origin and do not contain appreciable uranium.
The most recent reserve estimate by the U. S. Geological Survey
of the phosphate deposits of Florida is contained in an open file
report by V. E. McKelvey and others, 1953. This estimate was





C I


o1
. J










50



m 40
Oa.


0"<5

U 30

0 Z






Z-
030



0

YEAz



YEAR


~~ _Clt__ ____. _1____ I I I -


DISCOVERY
DATE
9-26-43


I I


DOTTED LINE INDICATE PUPING

SOLID LINES INDICATE ,LOWING


_ I I I 1 1 I i !


1944


1945 11946 11947 11948 11949 11950 11951 1952 1953


Figure 11
Production record of the Sunniland Field, Collier County.


-. .. .......


/..~


..........

**.u ~ n a. n** neco non ueen ... **** *** eane eae o .....i......
*" *
***** *
********** .ce******** **es ***c****.*


...........





36 FLORIDA GEOLOGICAL SURVEY-BULLETIN THIRTY-NINE

published in U. S. Bureau of Mines Minerals Yearbook 1953, vol.
1, and table 2 summarized the data for Florida.

Table 2
Production and Reserves of Phosphate Rock in Florida
in Millions of Long Tons

Production Inferred Reserves
From beginning of Minable under Minable under
Mining through 1949 present conditions changed conditions
Marketed PO2. Marketable P20, Product P20s
Product Product
Florida:
Land-pebble:
Matrix 124.7 41.7 1,000 330 2,000 600
Leached zone -. -. -.. 800 180
River pebble 1.3 .3 --.- 50 12
Hard-rock 14.0 4.8
Hard-rock 14.0 48 1,040 330 500 140
Soft-rock 1.1 .2
Hawthorn
formation __-__- -- 20,000 4,000

Total 141.1 47.0 2,040 660 23,350 4,932
U. S. Total 195.0 62.0 5,100 1,500 49,000 12,000


Source: McKelvey, V. E., and others, Domestic Phosphate Deposits, U. S.
Geological Survey Open File Report, 1953.

At the current rate of production, the inferred reserves minable
under present conditions will be sufficient for over 200 years and
the reserves minable under changed conditions would extend this,
perhaps, well over 1,000 years.
RIVER-PEBBLE AND LAND-PEBBLE

In 1881, Captain J. Francis Le Baron, U. S. Army, Corps of
Engineers, accidentally discovered the presence of rich phosphate
deposits in the "bed of Peace River." Mining of river-pebble phos-
phate by means of a floating steam dredge began in 1887. At the
heights of the river dredging era, some 12 companies were en-
gaged in the operations which were located on tributary streams
as well as on the Peace River itself. This precipitated a "boom"
period which affected Charlotte, Hardee, and DeSoto counties as





MINING AND MINERAL RESOURCES


7 7.-. .... ; .. .... . ... .!:. : : .- u

Figure 12
Sunniland Oil Field, Collier County, rework derrick in foreground and storage
tanks in background. F. S. N. B. photograph.
Published as Figure 4, 10th Biennial Report





38 FLORIDA GEOLOGICAL SURVEY-BULLETIN THIRTY-NINE

well as Polk County. These river operations consisted of pumping
the mixture of rock and matrix through flexible suction hoses con-
nected to 8-inch or 10-inch centrifugal pumps. The material was
put through a revolving screen in which the larger pebbles were
separated from the rest of the material, which was dumped back
into the river. The separated phosphate pebbles were discharged to
a nearby barge for transportation to Charlotte Harbor. Mining
operations continued in the river until 1908 when increased mining
costs and a slump in the market caused the cessation of operations.
The discovery of high grade land-pebble phosphate deposits and
the development of economical means for strip mining these de-
posits led to the growth of phosphate operations in ever increasing
magnitude from 1891, the year the first shipments were made, until
1917 when the first World War caused the loss of a lucrative export
business and another depression period for the industry. Follow-
ing World War I, the course of production was upward and the
industry continued to flourish until the second World War again
curtailed operations. In the intervening years, however, new uses
and techniques for using phosphates had developed and these,
together with the tremendous needs for rebuilding agriculture in
Europe and feeding devastated -countries until such rebuilding
could be accomplished, led to the industry's rapid expansion during
the post-war years.
The main portion of the land-pebble field covers approximately
2,600 square miles in Polk, Hillsborough, Manatee, and Hardee
counties. Known boundaries of the field extend into Highlands,
DeSoto, and Sarasota counties, and other deposits of land-pebble
phosphate are known in Hamilton, Clay, Lake, and Orange coun-
ties. Since 1905, the mines in Polk and Hillsborough counties have
been the most important source of phosphate for American in-
dustry. The land-pebble district produces about 70 percent of the
phosphate rock mined in the United States and m6re than one-third
of the estimated production of phosphate'for the entire world.
In the portion of the land-pebble field under development, the
tonnage of recoverable phosphate ranges from 500 to 35,000 tons
per acre and is typically 5,000 tons per acre.
Mining and Processing: In former years, most of the rock was
mined from the bottom and edges of streams with floating hy-
draulic dredges that discharged the spoil back into the river. This
method of recovery produced "river-pebble phosphate" and the
broad stream beds that exist in the headwaters of the Alafia, Peace,
and other rivers were formed during these dredging operations.
Modern mining methods utilize huge draglines and complicated




MINING AND MINERAL RESOURCES


washers, crushers, screens, hydraulic separators and flotation
plants in which practically all particles of phosphate rock that are
larger than 200 mesh are recovered. The industry has developed
earth moving equipment and techniques that are in themselves
modern industrial miracles. Draglines that consume 29 cubic
yards at a scoop, water systems to supply 150 million gallons a
day from wells with capacities up to 26,000 gallons a minute, flo-
tation plants to produce a million tons of high grade phosphate a
year are a portion of the land-pebble industry.
The huge quantities of water and the suspended slimes and clays
removed from the matrix are pumped to large settling lagoons for
clarification and, if possible, for reuse of the water. The larger
solids may be discharged to separate "tailing" ponds or may be
deposited near the point of influent to the slime'pond. The semi-
colloidal slimes are distributed more or less evenly throughout the
lagoon. These slimes occupy more volume than the removed ma-
terial, consequently, even if the mined-out areas are utilized,
storage must be provided above the ground surface. These storage
lagoons cover areas upward to 1800 acres and are frequently sub-
divided into several lagoons for better control. The clear water
that accumulates above the slime layer may be re-used by the plant
or may discharge into streams. The accidental discharge of slimes
into streams through dam failure brought about by faulty struc-
tures, excessive rainfall, or other reasons, continue to be a matter
of concern to the industry, property owners and others that utilize
the rivers.
The land-pebble phosphate field produces and ships about 10
million tons of phosphate rock annually, all of which is a concen-
trate obtained by scrubbing, screening and flotation processes. To
obtain that quantity of commercial-grade rock, it is necessary to
treat approximately 30 million tons of ore (matrix) and to remove
another 30 million tons of overburden. The character of the rock,
the climate, and the abundance of both surface and subsurface
water all contributed to the development of hydraulic mining and
hydraulic transportation of the ore throughout the district. Min-
ing and processing in the land-pebble phosphate district is char-
acterized by the use of huge draglines, the use and reclamation of
large volumes of water, and the disposition of great volumes of
slimes. The outstanding feature of mining practice established in
the district is the use of large draglines by each of the eight pro-
ducing companies. Within the district, there are 12 large drag-
lines that have bucket capacities of 14 to 29 cubic yards, and 14
smaller draglines with bucket capacities of 6 to 10 cubic yards. The















































Figure 13
Noralyn mine and plant of the International Minerals and Chemical Corporation,
Bartow, Polk County. F. S. N. B. photograph.
Published as Figure 7, 10th Biennial Report


.m4r


::
: . ~~ ~~!:r




MINING AND MINERAL RESOURCES


large draglines are of the Monighan walking type, have boom
lengths from 175 to 235 feet, and digging capacities from 1,000 to
2,000 cubic yards per hour. The most common dragline is the Bu-
cyrus-Erie 650B, equipped with a 175-foot boom and a 17-cubic
yard bucket, that can dig an average of 1,100 cubic yards per hour.
The largest machine, named the "Super-Scooper," is a Bucyrus-
Erie 1250B walking dragline, which swings a 29-cubic yard bucket
on a 235-foot boom.
After the overburden is stripped and placed in either single
or double windows, the ore or matrix is excavated, lifted to ground
level, and dumped into a "well" or depression dug about six feet
below ground level by a bulldozer where hydraulic monitors play
water upon the matrix which disintegrates and is sluiced through
a grizzly into a sump. The slurry is pumped from the well by large
electrically driven centrifugal pumps and is transported in 16-inch
pipelines to the washing plant. Standard in the field is a 14-inch
pump with a 34 to 40-inch in diameter impeller that can handle a
maximum rock size of six inches in diameter. These pumps are
coupled directly to 500 to 800-horsepower electric motors and
usually handle 5,000 gallons of water per minute in which from 10
to 15 cubic yards of solids are suspended. They normally deliver
7,000 to 8,000 gallons per minute of slurry that contains from 25
to 45 percent solids or 500 to 600 cubic yards of matrix per hour.
Depending upon the condition of the matrix, the ratio of coarse
to middle to fine sizes, the stratification in the lines and other fac-
tors, the pumps occasionally may deliver from 800 to 1,000 cubic '
yards per hour. As the distance between the sump and the washer
increases, booster pumps are added to the line. One pump carries
about 11/2 miles of pipeline and lines that are four or five miles long
are common in the field. One company operates a six-mile long
line. The pipeline delivers the mined material to the washing plant
and the solids have been in the line an average of 8 to 10 minutes
for each mile traveled.
Beneficiation of the land-pebble phosphate is illustrated in the
flow sheet of the washer and flotation plants (fig. 15).
At the washer, the incoming matrix is separated into three
portions-the fines (minus 14 mesh) go to the flotation plant; the
coarse (larger than 7/8 inch) are crushed, reduced in size, and
re-circulated; and the middlings (plus 14 mesh, minus 7/8 inch)
are called "pebble phosphate rock" or "washer rock." Generally
two sizes are separated, the finer fraction (minus 5 mesh, plus
14 mesh) being somewhat higher grade than the coarser fraction
(plus 5 mesh, minus 7/8 inch). After the pebble has been removed





42 FLORIDA GEOLOGICAL SURVEY-BULLETIN THIRTY-NINE.


Figure 14
Preparing matrix for pipeline transportation. As the matrix or ore bed in the land-
pebble phosphate field is mined by dragline and dumped into a well, hydraulic guns
transform it into a slurry which is pumped to the washery. F. S. N. B. photograph.
Published as Figure 8, 10th Biennial Report

in the washer, the remaining portion of the slurry goes to a flo-
tation plant where additional sizing and concentration is carried
out. The largest fragments (plus 14 mesh) that were not removed
by the washer are recovered as "pebble phosphate rock," the mid-
dle fractions (minus 14 mesh, plus 35 mesh and minus 35 mesh
plus 150 mesh) receive further treatment and the finest fraction
constitutes the slimes. The coarser portion of the middle fraction
receives various treatments, depending on the individual plant;
nevertheless, the material is treated with reagents and the phos-
phate grains are separated from the quartz grains by use of vi-
brating tables, Humphrey spirals, conveyor belts, or coarse-feed
cells. The coarse concentrate is one product of the flotation plant.






MINING AND MINERAL RESOURCES 43


BENEFICIATION OF LAND-PEBBLE PHOSPHATE ORE
WASHER PLANT
SLURRY FROM MINE
(16" PIPE LINE)

INCLINED SCREEN
I I
PLUS 14 MESH MINUS 14 MESH

DOUBLE DECK
VIBRATING SCREEN
PLUS Y INCH PLUS 14 MESH MINUS 14 MS
DISINTEGRATOR I
AND PUMP ILOG WASHER

SINGLE DECK
VIBRATING SCREEN
PLUS 14 MESH MINUS 14MESH
I
LOG WASHER

DOUBLE DECK
VIBRATING SCREEN
PLUS 5 MESH PLUS 14ME MINUS 14 MSH
TO BIN TO BIN

FLOTATION PLANT
FLOTATION PLANT FEED

| FEED BINS
UNDERFLOW OVERFLOW MINUSS 10 MESH)

HYDRAULIC SIZING UNITS O PARATOI
(DORRCO SIZERS) I Y O SEAR
PLUS 14 SH PLUS 35 M 35 MESH RFLOW
N E R TO SLIME
HU M S P IR A-, 1 DISPOSAL AREA
COARSER FEED BIN FINER FEED BIN
SPIRAL CLASSIFIERS SPIRAL CLASSIFIERS
DEWATERED FEED OVERFLOW OVERFLOW DEWA ERED FEED
AUSTIC SODA CAUSTIC SODA
TALL OIL FUEE OIL
T L L ITALL OIL
ROTARY CONDITIONER VERTICAL CONDITIONERS
DISTRIBUTOR FLOTATION CELLS

VIBRATING TABLES ROUGHER TAILINGS
HUMPHREYS SPIRALS CONCENTRATE TO SUMP
SE CEL LSTS OR WATERING CONE
COARSE FEED CELLS SULFURIC ACID
CONCENTRATE MIDDLING TAILS ULFUIC AD
TO BIN TO SUMP VERTICAL CONDITIONER
CAUSTIC SODA
TALL OIL I I WASHING CLASSIFIER
CONDITION NER OR WASH BOX
UNDERFLOW OVERFLOW
VIBRATING TABLES, "- -FLOW
HUMPHREYS SPIRALS, J
BELTS OR G I [SPIRAL CLASSIFIER
COARSE FEED CELLS DEWATERED FEED
CONCENTRATE MIDDLING TAILINGS CAUSTIC SODA
TO BIN TOSUMP KEROSENE
--AMINE
FLOTATION CELLS)
CONCENTRATE FROTH DISCHARGE
TO BIN TO SUMP

Figure 15
Generalized flow-sheet of a land-pebble phosphate washer
and flotation plant.





44 FLORIDA GEOLOGICAL SURVEY-BULLETIN THIRTY-NINE

The finer fraction of the flotation plant feed is dewatered, treated
with reagents, and fed into flotation cells, rectangular tanks con-
taining paddles which agitate the pulp and introduce air into the
mixture. The phosphate particles being coated with reagent are
attached to the air bubbles and are removed in the froth. The
concentrate is then treated with sulfuric acid to remove the reagent
and after washing is again treated in flotation cells. This step,
however, is the reverse of the first treatment inasmuch as the
quartz sand is floated out in the froth and the phosphate rock is
left behind. This nonfloat portion is the final concentrate of the
flotation plant and analyzes 32 to 35 percent P205. The "washer
rock" products and the flotation concentrates are stored in sepa-
rate bins from which they are transferred to wet storage prior
to drying and further treatment. The tailings, primarily of qaartz


Figure 16
Index map to mines and plants in the land-pebble phosphate rock district.





MINING AND MINERAL RESOURCES


sand, analyze 2 to 5 percent P2Os, and are pumped to waste ponds.
The principal mines and plants in the land-pebble phosphate
field are located by index number on the map of the district (fig.
16), and are identified in the accompanying listing.



LIST OF COMPANIES, MINES AND PLANTS IN THE
LAND-PEBBLE PHOSPHATE DISTRICT
(Refer to numbered localities on figure 16)


Company and Florida Address
American Cyanamid Company
Brewster


2 Coronet Division,
Smith-Douglas Co., Inc.
Plant City

3 American Cyanamid Company
Brewster

4 Davison Chemical Company
Bartow
5 Coronet Division,
Smith-Douglas Co., Inc.
Plant City
6 American Cyanamid Company
Brewster
7 Virginia-Carolina Chemical Corp.
Nichols






8 International Minerals and
Chemical Corp.
Bartow
9 F. S. Royster Guano Company
Mulberry

10 Davison Chemical Company
Bartow



11 Davison Chemical Company
Bartow


Index
No.
1


Installation
Orange Park mine
Washer and flotation plant
Teneroc mine
Washer and flotation plant
Wet storage
Drying and shipping installations
Saddle Creek mine
Washer and flotation plant
(to be abandoned 1957)
Pauway No. 4 mine
Washer and flotation plant
Main office
Drying and shipping installations
Defluorination plant
Sydney mine
Washer and flotation plant
Main office
Drying and shipping installations
Electric furnace-elemental
phosphorus
Superphosphate plant
Triple superphosphate plant
Synthetic cryolite plant
Uranium recovery plant

Mulberry research laboratory
Drying and shipping installations

Triple superphosphate plant


Main office
Ridgewood washer and table
concentration plant
Drying and shipping installations
Triple superphosphate plant
Bonny Lake mine






46 FLORIDA GEOLOGICAL SURVEY-BULLETIN THIRTY-NINE

12 Armour Fertilizer Works, Inc. Main office
Bartow Bartow mine
Washer and flotation plant
Triple superphosphate plant
13 Virginia-Carolina Chemical Corp. Phosmico flotation plant
Nichols Drying and shipping installations
14 International Minerals and Main office
Chemical Corp.
Bartow
15 International Minerals and Bonnie triple superphosphate
Chemical Corp. plant
Bartow Uranium recovery plant
16 International Minerals and Achan mine
Chemical Corp. Washer and spiral plant
Bartow
17 American Agricultural Main office
Chemical Co. Drying and shipping installations
Pierce Electric furnace-elemental
phosphorus
Superphosphate plant
18 International Minerals and Noralyn mine
Chemical Corp. Washer and flotation plant
Bartow Drying and shipping installations
19 Virginia-Carolina Chemical Corp. Clear Springs mine
Nichols Washer plant
(flotation feed is pumped to
Phosmico plant-No. 13 above)

20 Virginia-Carolina Chemical Corp. Homeland mine
Nichols Washer and flotation plant
21 International Minerals and Peace Valley mine
Chemical Corp. Washer and flotation plant
Bartow
22 Swift and Company Main office
R.F.D. Agricola drying and shipping
Bartow installations
Triple superphosphate plant
23 American Agricultural Boyette mine
Chemical Co. Washer and flotation plant
Pierce
24 American Cyanamid Company Main office
Brewster Drying and shipping installations
Triple superphosphate plant
25 American Agricultural South Pierce tract, No. 12 mine
Chemical Co.
Pierce
26 Swift and Company Watson mine
R.F.D. Washer and flotation plant
Bartow
27 Swift and Company Varn mine
R.F.D. Washer and flotation plant
Bartow






MINING AND MINERAL RESOURCES


The phosphate mined in the 14-year period 1943-1956 inclu-
sive, equals the quantity produced in the 55-year period 1888-1942
inclusive. The value at the mines as reported by producers during
the past nine years, 1948-1956 inclusive, is equal to the cumulative
value of the previous 60 years, 1888-1947 inclusive.


Table 3

Production and Value of Phosphate Rock Mined in Florida from the
Beginning of Mining in 1888 through 1956 (Includes Land-Pebble,
Hard-Rock, Soft-Rock, and River-Pebble Phosphate)


Value
$ 21,000
28,000
338,190
703,013
1,418,418
1,979,056
1,666,813
2,112,902
1,547,353
1,493,515
1,847,796
2,804,061
2,983,312
3,159,473
2,564,197
2,986,824
3,974,304
4,251,845
5,585,578
6,577,757
8,484,539
8,541,301
8,647,774
9,473,638
9,461,297
9,563,084
7,354,744
3,762,239
4,170,165
5,464,493
6,090,106
7,797,929
19,464,362
10,431,642
8,347,522


Year
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
TOTAL


Quantity in
Long Tons
2,547,653
2,432,581
2,929,964
2,708,207
2,637,420
2,883,446
3,088,298
3,248,071
2,061,466
1,469,976
2,136,123
2,369,334
2,422,804
2,624,900
2,996,820
2,707,335
2,678,784
2,845,012
3,365,572
3,012,240
3,588,493
3,752,795
4,238,228
5,005,511
6,482,027
6,539,258
6,815,989
8,085,870
8,496,831
8,781,125
9,166,855
10,437,197
8,747,282
10,500,000
197,101,313


Quantity in
Long Tons
3,000
4,100
46,501
112,482
287,343
438,804
527,653
568,061
495,199
552,342
600,894
726,420
706,243
751,996
785,430
860,336
1,072,951
1,194,106
1,304,505
1,357,365
1,692,102
1,779,702
2,067,507
2,436,248
2,406,899
2,545,276
2,138,891
1,358,611
1,515,845
2,022,599
2,067,230
1,660,200
3,369,384
1,780,028
2,058,593


Year
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922


Value
$9,059,427
8,017,476
8,789,070
8,683,508
8,646,162
9,424,022
9,901,074
10,790,305
7,202,086
4,779,612
6,417,110
8,076,317
8,361,558
8,528,523
9,142,985
8,773,680
7,893,457
7,741,177
10,234,031
9,378,577
12,089,477
13,534,947
16,298,474
21,017,174
32,920,252
37,732,894
37,857,983
45,377,842
50,262,562
51,541,799
55,612,272
65,499,877
53,640,301
65,920,000
$904,244,253





48 FLORIDA GEOLOGICAL SURVEY-BULLETIN THIRTY-NINE

HARD-ROCK AND SOFT-ROCK

In recent years, only one company has produced hard-rock phos-
phate but several small companies have been active in producing
soft-rock phosphate from the waste ponds of former hard-rock
operations. The combined production from these operations con-
stitutes only a minor portion of the quantity of phosphate rock pro-
duced in Florida. In 1942, the production record (table 4), shows
the combined tonnage of hard-rock and soft-rock phosphate was
about four percent of the total produced in the State. More recent-
ly, every year since 1948, the combined tonnage of hard-rock and
soft-rock phosphate has been less than two percent of the total
quantity produced. Neither the production of hard-rock nor of
soft-rock phosphate contributes a significant amount to the phos-
phate industry. Under changed economic conditions, the hard-
rock reserves of the State again may be mined.

USES

The principal use of phosphate rock is in the production of
superphosphate for use as a fertilizer. Under natural conditions,
the phosphorus taken up by plant growth is returned to the soil
upon the death and decay of the plant, and the efficiency of the
soil is maintained. Under cultivation of soil, the phosphorus is
removed with each crop that is harvested and, if the productivity
of the soil is to be maintained, the phosphorus must be replaced in
the form of superphosphate or some other soluble phosphate. Fine-
ly divided phosphate rock, phosphatic clay, or colloidal phosphate,
however, is used successfully as a fertilizer in regions of heavy
rainfall. In fertilizers such as superphosphate, which is made by
treating phosphate rock with sulphuric acid, the phosphorus is
available to plants in a much more soluble form than in the un-
treated phosphate rock. This available phosphorus is determined
in the form of phosphorus pentoxide, P205, and ordinary super-
phosphates contain 17 to 22 percent available PO2. "Triple" or
"double" superphosphate may be prepared by treating phosphate
rock with concentrated phosphoric acid and the product contains
40 to 50 percent available P205. A product containing calcium
metaphosphate that analyzes 60 percent available P20, is obtained
by the action of phosphoric anhydride on phosphate rock. The chief
advantage of these higher-grade fertilizers over the ordinary
superphosphate is that they are more concentrated, and smaller
expenditures for handling and transportation are possible.




Table 4
Mineral Industry in Florida 1942-1955


Mineral Product (1)


Clays (including kaolin
and fuller's earth)
Clay sold or used in ce-
ment manufacture
Diatomite
Lime
Natural gas, 1,000 cu. ft.
Oyster shell
Peat
Petroleum, 42 gal. bbls.
Phosphate rock (4) -long tons
Land-pebble long tons
Hard-rock long tons
Soft-rock long tons
Sand and gravel
Stone (except limestone
for cement and lime)
Ilmenite
Rutile
Zircon
Undistributed


1942


Quantity


53,458
(2)
(2)
21,510
(2)
2,400
3,012,240
2,893,756
70,014
48,470
1,834,863
6,632,680
(2)
(2)
(2)
---------


Value


1943


1944


1945


1946


1947


H II II NI I


Quantity


Value


Quantity


Value


Quantity


Value


Quantity


Value


Quantity


Value


1948


Quantity


I II- 41-----------1 4 ~ II -~--I 41 I 11 --~- ~I IL ________ 1


$ 717,749
(2)
(3)
212,291
(2)
12,600
9,378,577
8,826,705
396,527
155,345
1,339,361
5,733,697
(3)
(3)
(3)
3,470,022


58,533
(2)
(2)
20,507
(2)
7,316
4,032
3,588,493
3,483,194
34,128
71,171
1,833,453
8,741,200
(2)
(2)
(2)
---------


$ 835,649
(2)
(3)
202,276
(2)
16,950
(3)
12,089,477
11,633,241
201,241
254,995
1,527,985
7,446,388
(3)
(3)
(3)
3,649,493


64,329
35,089
(2)
17,959
(2)
3,100
11,838
3,752,795
3,607,208
22,500
60,087
1,335,569
2,730,020
21,386
3,730
(2)


$ 917,526
17,544

(3)
185,565
(2)
30,000
(3)
13,534,947
13,136,472
138,952
259,523
1,180,299
2,600,462
422,440
588,120
(3)
3,339,699


64,436
41,266
(2)
18,431
6,000
15,231
15,194
27,510
4,238,228
4,103,022
63,491
71,715
1,314,011
2,617,180
(2)
(2)
(2)
----------


$ 964,442
20,633
(3)
211,077
180
119,303
66,747
(3)
16,298,474
15,578,980
426,061
293,433
1,074,055
3,024,465
(3)
(3)
(3)
3,941,233


93,438
35,000

(2)
6,000
(2)
19,979
56,884
5,005,511
4,807,563
100,881
97,067
1,534,667
2,863,070

(2)
(2)
(2)


$ 1,206,412
17,500

(3)
193
(2)
81,832
(3)
21,017,174
19,867,339
762,127
387,708
1,320,819
3,212,135

(3)
(3)
(3)
5,005,456


110,214
42,000

(2)
8,000
42,300
259,345
6,482,000
6,314,077
79,330
88,620
2,067,000
3,534,000
(2)
(2)
(2)


$ 1,448,468
21,000

(3)
258
126,000
(3)
32,920,000
31,975,858
618,330
326,064
1,881,000
4,512,000

(3)
(3)
(3)
5,901,000


111,337
49,000

(2)
27,000
24,750
291,221
6,539,000
6,421,725
48,198
69,335
2,312,000
4,155,000
(2)
(2)
(2)


Value


$ 1,636,912
37,000

(3)
1,000
56,171
(3)
37,733,000
37,070,381
368,586
293,927
2,433,000
5,116,000

(3)
(8)
(3)
8,315,000


Total $20,303,948 $25,070,000 $21,852,000 $24,928,000 $31,093,000 $45,847,000 $53,654,000



1949 1950 1951 1952 1953 1954 1955

Mineral Product (1) Quantity Value Quantity Value Quantity Value Quantity Value Quantity Value Quantity Value Quantity Value

Clays (including kaolin 96,000 $ 1,447,000 127,000 $ 1,955,000 133,000 $ 2,289,000 112,113 $ 1,985,587 148,000 $ 2,842,448 371,948 $ 3,337,130 412,766 $ 4,815,855
and fuller's earth)
Clay sold or used in ce- 80,000 40,000 84,000 63,000 70,000 70,000 86,000 86,000 109,911 109,911 (2) (3) (2) (3)
ment manufacture
Diatomite --m-tmna ---------- --------- -------- -
Lime (2) (3) (2) (3) (2) (3) (3) (3) (2) (3) (2) (3) (2) (3)
Natural gas, 1,000 cu. ft. 39,000 2,000 8,000 (3) 10,000 1,000 15,000 1,000 34,000 2,000 35,000 2,900 35,000 4,000
Oyster shell 724,342 1,653,669
Peat 11,800 69,000 23,022 151,000 25,748 161,000 23,729 154,164 27,678 185,524 37,449 168,004 61,098 231,829
Petroleum, 42 gal. bbls. 441,720 (3) 486,021 (3) 596,043 (3) 591,855 (3) 541,284 (3) 548,000 (3) 490,000 (3)
Phosphate rock (4)-long tons 6,816,000 37,858,000 8,086,000 45,378,000 8,497,000 50,263,000 9,205,138 54,085,524 9,330,952 56,587,790 10,437,197 64,499,877 8,747,282 53,640,301
Land-pebble long tons 6,715,097 37,339,985 7,933,009 44,430,646 8,329,033 49,185,072 9,036,237 52,931,460 9,185,971 55,575,120 10,288,332 63,301,900 8,586,294 52,545,200
Hard-rock long tons 23,804 173,211 71,319 538,601 75,615 582,247 85,900 662,289 68,200 537,400 78,990 622,440 91,200 733,800
Soft-rock long tons 77,088 344,787 81,542 408,595 92,183 495,243 83,001 491,775 76,781 475,270 93,956 575,537 69,788 452,301
Sand and gravel 2,244,000 1,880,000 2,794,000 2,807,000 4,419,000 4,301,000 4,154,613 3,848,077 3,731,432 3,199,368 3,468,842 2,661,152 5,065,503 4,349,148
Stone (except limestone 4,215,000 4,748,000 5,313,000 6,885,000 8,033,000 9,420,000 7,836,634 9,577,541 9,428,959 11,309,421 14,225,356 16,832,066 16,303,625 21,312,339
S for cement and lime)
gmenite (2) (3) (2) (3) (2) (3) (2) (3) 151,109 2,322,451 157,157 2,411,823 (3) (3)
e 2) (3) (2) (3) (2) (3) (2) (3) 6,475 702,791 7,305 869,677 (3) (3)
ircon (2) (3) (2) (3) (2) (3) (2) (3) 21,234 793,685 17,959 820,041 28,913 1,425,641
tJdistributed 9,014,000... 10,541,000 --12,113,000 ....13,226,587 ..-_ 14,453,548 14,913,943 23,868,651


Total


$55,018,000


$67,717,000


$78,548,000


$82,878,000


$92,336,000


$106,517,000


I I 1 11 __ ii I I_


$108,917,000


(1) Reported in short tons unless indicated otherwise.
(2) Data not available.
(8) Value included under "undistributed."
(4) 1942-1951 inclusive phosphate reported on sold or used basis.
1952-1955 inclusive reported on marketable production basis.


*** ...





MINING AND MINERAL RESOURCES


There is a trend in the phosphate district toward increased
numbers of phosphate processing plants and this industrial growth
has been stimulated by the increased use of triple superphosphate
and the recovery of uranium as a by-product. Triple superphos-
phate is manufactured by treating phosphate rock with an excess
of sulfuric acid to form phosphoric acid, and then treating more
phosphate rock with the phosphoric acid to form the so-called
triple superphosphate, a product that contains about three times
as much available phosphate (expressed as P205) as would be ob-
tained by treating phosphate rock with a limited amount of sul-
furic acid in a single operation. The by-product uranium is re-
covered from the phosphoric acid that is produced in the first step
of the process. Gypsum (CaSO4) and soluble fluorine compounds

Table 5

Consumption of Phosphate Rock Produced in Florida
in 1954 by Uses

1954
Land-pebble Long Tons
Ordinary superphosphate 4,912,435
Triple superphosphate 1,036,406
Nitra phosphate 12,851
Direct application to soil 577,231
Stock and poultry feed
Fertilizer filler
Elemental phosphorus, ferro-phosphorus,
and phosphoric acid 622,563
Phosphoric acid (wet process) 439,056
Exports 1,061,619
Total 9,565,529

Hard-rock
Elemental phosphorus, ferro-phosphorus,
and phosphoric acid 74,303

Soft-rock
Direct application to soil 90,519
Stock and poultry feed9019
Total 9,730,351

are likewise produced. The gypsum collects in settling ponds but
the soluble compounds may be present in the waters that discharge
from the ponds. Fluorine compounds are likewise formed in the
second step of the process for triple superphosphate manufacture
and, together with other stack gases (sulfur dioxide and carbon





50 FLORIDA GEOLOGICAL SURVEY-BULLETIN THIRTY-NINE

dioxide) are captured by scrubbing with water. The whole new
industry of synthetic detergents is a development of industrial
chemical research in the discovery of new phosphate chemicals and
their utilization. The expanded use of household detergents and
water softeners has created an increased demand for elemental
phosphorus.
ORIGIN

The traditional explanation of phosphate origin has been seri-
ously challenged in recent years by a theory which proposes pre-
cipitation of calcium phosphate from sea water. While it is recog-
nized that significant amounts of phosphate are derived from the
decay of organic matter, major quantities are formed by chemical
precipitation. The depth of water at which phosphate precipita-
tion occurs is an important factor in establishing the environment
for precipitation from sea water. The theory as originally pre-
sented suggests that the zone of deposition would lie between
depths of 150 and 600 feet. The depth of this zone, however, has not
been established and many deposits, including those of the land-
pebble district, suggest that the deposition occurred in shallow
water. The question of water depth is still an open issue and the
mechanics of moving the upwelling water across wide shelf areas
has been given as an objection to this theory. Such an objection
may not be valid in the case of the Florida deposits because up-
wellings that bring phosphatic waters from depth to the surface
are known to occur in the Gulf of Mexico, and strong surface cur-
rents that act much like the jet streams in the atmosphere have
been recorded. Such currents are believed to be the source of the
phosphate concentration associated with the so-called red-tide
condition that sometimes occurs in the Gulf waters west of the
peninsula of Florida. Such currents offer a plausible explanation
not only for the establishment of a phosphate cycle but also for
phosphorite precipitation from sea water and its deposition in
shallow water.

ALUMINUM

The discovery of a continuous reduction process in 1886 marked
the beginning of aluminum as a commercial metal. Its widespread
use in both metallic and nonmetallic applications has occurred
during the past 50 years. Aluminum is the most abundant metallic
element in the earth's crust and among all metals it is second only
to iron in volume of production. Bauxite, the principal ore of














z













Figure 17
Kibler-Camp Phosphate Enterprise, Sec. 18 Mine, Citrus County. The only company
and mine producing hard-rock phosphate in Florida.





52 FLORIDA GEOLOGICAL SURVEY-BULLETIN THIRTY-NINE

aluminum, is used in the production of metal, synthetic abrasives,
chemicals and refractories.
In the United States, bauxite production began in Georgia in
1889 but for every year since 1905 over one-half of the domestic
production has come from Arkansas. Relatively small quantities
of bauxite have been mined in Tennessee, Virgina, and Missis-
sippi but in recent years, Arkansas, Alabama, and Georgia have
been the only producing states. The North American continent
has limited reserves of bauxite, and about 60 percent of the quan-
tity used in the United States has been imported from British
Guiana. Expansion of the aluminum industry during and after
World War II brought about increased demands which are being
met by shipments from the huge deposits in Jamaica. During
1942, enemy submarine activity in the Caribbean seriously cur-
tailed shipments from South America and demonstrated the need
for economical processes to utilize the vast quantities of low grade
alumina materials which would substitute for bauxite. Extensive
research programs have been conducted by federal agencies and
by industry to find and develop competitive methods for the re-
covery of alumina from clay and other materials. In the land-
pebble phosphate district, both the raw matrix, which is the com-
mercial source of phosphate rock, and that portion of the over-
burden which consists of the altered zone of aluminum phosphate
offer potential sources for alumina production. The fine or minus
150-mesh fraction of the matrix and the aluminum phosphate zone
of the overburden contain from 15 to 30 percent of A1203 and of
P205. More than 25,000,000 tons of raw matrix are mined annually
to produce 10,000,000 tons of phosphate rock and pebble concen-
trate, and it is estimated that 14,000,000 tons of aluminum phos-
phate which occur in the overburden are moved and discarded as
waste. The utilization of these materials and their potential ex-
ploitation to produce not only phosphate for fertilizers, but also
co-product and by-product recovery of alumina, fluorine, uranium,
and possibly other materials of value, is under investigation.

PORTLAND CEMENT

In the United States, the manufacture of portland cement has
grown to become the largest single industry in the entire field
of nonmetallic industrial minerals. In 1954, the value of portland
cement constituted nearly 30 percent of the value assigned to the
nonmetallic minerals (fuels excluded) that were produced in the
country. Cement is so low priced, easy to use, and durable that it





MINING AND MINERAL RESOURCES


has become the foundation stone of the construction industry. The
first manufacture of portland cement in the United States was
made in 1871 in the Lehigh Valley of Pennsylvania and produc-
tion in the United States has increased steadily to reach the
enormous production in 1955 of 292,600,000 barrels, valued at
$791,000,000. Although data on the quantity of cement manufac-
tured in Florida are unavailable, nearly 9,000,000 barrels were
used in the State during 1955. During that year, the per capital
use of cement in Florida was 2.67 barrels, and in the United States
1.80 barrels. Florida ranks third among the States in per capital
use of portland cement and ninth in total quantity used.
Portland cement is produced by heating or calcining a finely
ground artificial mixture of lime, silica, alumina, and iron oxide
in a rotary kiln to form a silicate clinker which is then pulverized.
Definite proportions of these ingredients are necessary to produce
a satisfactory product. Natural cement is produced by calcining
at relatively low temperatures an impure limestone that contains
the necessary proportions of silica, alumina and iron oxide. Ma-
sonry (natural) cement is a special type of natural cement that is
suitable as a mortar for bricks or other masonry work. Pozzolanic
cement is produced by mixing powdered slaked lime with either
volcanic ash or pulverized blast-furnace slag. This material differs
from a slag portland cement in that the mixture is not calcined.
All of these varieties of cement are classified as "hydraulic" inas-
much as they will set or harden under water. Portland cement,
however, is most widely known and used because manufacturers
are able to control the properties of the product by proportioning
the ingredients of the mixture from which it is made.
Many different raw materials theoretically may be used in
portland cement manufacture but only a few are actually used.
Some argillaceous limestone, or natural cement rocks, have the
approximate proportions of lime, silica, iron and alumina neces-
sary for portland cement, while others require additions of minor
quantities of one or more of these materials to produce the proper
chemical mixture. More often, however, the necessary lime is
supplied by one material (limestone, shells, or marl), the silica by
sand or sandstone (or as a portion of the clay or shale that is
used), the alumina by clays and shales, and the iron oxide by iron
ore, or by high iron clays or shales.
The huge kilns in which portland cement is manufactured rank
in size with the largest pieces of moving equipment that are used
by any industry. At the Lehigh Portland Cement Company's Bun-
nell plant, rotary kilns that are 101/2 feet in diameter and 380 feet





54 FLORIDA GEOLOGICAL SURVEY-BULLETIN THIRTY-NINE

long are in use, while those at the Tampa plant of the General
Portland Cement Company, Florida Portland Cement Division,
are 426 feet long. The capacity of the Tampa plant has been in-
creased from 1,500,000 barrels at the end of World War II to
4,000,000 barrels annually as of January 1955. The Bunnell plant
was completed in December 1952, at a designed capacity of
1,400,000 barrels. A plant expansion program, completed in 1956,
increased the annual capacity to 2,500,000 barrels. Although the
actual production data from these plants are not available, the
demand for cement in Florida is much greater than the combined
capacity of the plants. The quantity of portland cement sold and
used in the State increased from two million barrels in 1945 to
nearly nine million barrels in 1955. It is also reported that
2,500,000 barrels of cement were shipped to Florida from Puerto
Rico, and 900,000 barrels from Europe during 1955.
The great strength of concrete masonry structures is illus-
trated by their remarkable resistance to windstorms. One of the
most severe storms ever experienced in this country is believed
to have been the 1926 Florida hurricane. Wind velocities soared
as high as 125 m.p.h. and in some areas rainfall amounted to 15
inches during the 16 hours of the storm. The City of Coral Gables,
then the only city in the United States restricted by law to con-
crete construction, was in the direct path of the hurricane. Some
2,500 residences, apartments, and other buildings, all of concrete
masonry construction, survived with only slight damage. There
was not a single instance of total destruction. The inherent
strength of concrete masonry construction is desirable in any
structure and that type of building predominates throughout Flor-
ida. A property owner may prefer to build principally with wood
or brick rather than with concrete block or poured concrete, but
almost without exception, every structure uses a certain quantity
of cement in foundation, basement, mortars, floor or roof. The
choice of principal structural material is governed by many factors
including cost, personal preference, and building code specifications.
Significant trends in the use of portland cement include the pre-
stressing of concrete to impart sufficient strength in order that
concrete beams and girders may be substituted for structural steel;
the use of lightweight concretes to save structural steel, and the
development of tilt-up construction of houses and small-sized com-
mercial buildings. Information concerning these and other uses
may be obtained from the Portland Cement Association, 33 West
Grant Avenue, Chicago 10, Illinois, or their district office in Or-
lando, Florida.





MINING AND MINERAL RESOURCES


The raw materials that are used by the General Portland Ce-
ment Company, Florida Division, Tampa, and produced by that
company in the State are limestone and clay. Huge quarries for
limestone are situated in Hernando County, near Gay, and in Citrus
County, a few miles southwest of Floral City. Clay is obtained
from a pit located in the southern portion of Citrus County. The
raw materials produced in Florida that are used in the manufac-
ture of portland cement at the Bunnell plant of the Lehigh Port-
land Cement Company are coquina and staurolite. The coquina
is dredged from a quarry located adjacent to the plant and it con-
sists of shell and sand of the Anastasia formation. The shell is
separated from the sand and a portion of the latter is recombined
with the shell in order to produce the correct proportion of calcium
and silica. The mineral staurolite, a by-product of the Trail Ridge
heavy mineral separation plant, is used to supply the alumina and
a portion of the iron that is required by the cement formula. The
elevation of the staurolite to the rank of an industrial mineral was
accomplished by its utilization in portland cement manufacture at
the Bunnell plant of the Lehigh Portland Cement Company.
Portland cement is usually packed in 94-pound paper bags,
which is equivalent to one cubic foot. The unit of measure in re-
porting cement production is the 376-pound barrel which is equiva-
lent to four 94-pound bags. The average value of portland cement
in the United States rose from $1.46 per barrel in 1940 to $2.35
per barrel in 1950, to $2.86 per barrel in 1955. The average value
of the Florida product is somewhat higher than that of the national
average.
The cost of construction of portland cement plants ranges be-
tween $7 and $10 per annual barrel of capacity, with a minimum
economic capacity of about 600,000 barrels per year. The high
initial cost of a new plant has discouraged investment of capital
by sources not already concerned with cement production. During
1956, both of the producing companies in Florida announced plans
to construct new portland cement plants to be located a few miles
west of Miami. The General Portland Cement Company will have
a capacity of 2,500,000 barrels annually and is scheduled to begin
operations late in 1957 or early in 1958. The Lehigh plant will
have a capacity of 2 million barrels.





56 FLORIDA GEOLOGICAL SURVEY-BULLETIN THIRTY-NINE

CLAY

GENERAL STATEMENT AND CLASSIFICATION

Clays are hydrous aluminum silicates mixed with varying pro-
portions of impurities. These silicates occur in many mineral
forms, each of which has distinctive properties that give rise to
the suitability of the different clays to particular industrial uses.
The principal industrial clays are kaolin or china clay, ball clay,
fire clay, bentonite, fuller's earth, and miscellaneous or "common"
clays. About three-quarters of all the clay that is produced enters
into the manufacture of ceramic products. Kaolin is used for
whitewares, cement, fillers, and other applications. Ball clays and
fire clays are used by the ceramic industry. Bentonite and fuller's
earth are used for clarifying and cracking petroleum products,
foundry facings, drilling muds, insecticide carriers and other non-
ceramic purposes. Miscellaneous clays include those materials gen-
erally referred to as common clays and are used for manufacturing
heavy clay products such as brick and tile and portland cement.
The different types of clay have distinctive properties; never-
theless, these properties show considerable variation within the
same type. Significant properties of clays that are used for ce-
ramic purposes include plasticity, dry and fired color, dry and fired
strength, dry and fired shrinkage (or expansion), fired apparent
porosity, density, softening point on firing, vitrification range,
bloating, adsorption, and particle size and shape. Significant prop-
erties for nonceramic uses vary with use and include texture, free-
dom from grit, color, relative decolorizing ability and oil retention.
No two clays are exactly alike and it is seldom possible to sub-
stitute one clay for another without extensive experimentation.
Most ceramic bodies contain several clays and any change in com-
position results in uncertain firing behavior. For this reason, ce-
ramic raw materials are usually produced for long periods of time
and ample reserves are required before development and prouuc-
tion can begin.
Each clay possesses a number of characteristics that are more
or less common to other clays, even though their physical and
chemical compositions may have wide variations. For most pur-
poses, the chemical composition is of little importance and chemical
analyses serve only to indicate further investigation for a specific
purpose or composition. The cost of such analyses may exceed that
of a simple ceramic test which might be more meaningful to a
competent clay technologist. In spite of the great advances that





MINING AND MINERAL RESOURCES


have been made during recent years in the field of ceramics and
clay technology, many of the significant properties of clay are still
evaluated by rule-of-thumb methods.
The crystallographic structure and chemical composition of
clay minerals have undergone extensive investigations during the
past 15 years and new mineralogic classifications have been made.
Clay minerals fall into three main structural categories. Most of
the clay minerals fall into the layer-silicate types composed of
micaceous or platy structures. This type is further subdivided into
groups according to the characteristics of the layered structure.
With reference to figure 18, it may be seen that the clay minerals
having layered structures fall into the kaolinite group, the mont-
morillonite group, the illite group and the mixed layer group. The
clay minerals of the chain-silicate type have fibrous structures and
are classified in the palygorskite group. Clay minerals that have an
amorphous silicate structure are classified in the allophane group.
KAOLIN

Kaolin, or china clay, is a mixture of clays that has the mineral
kaolinite as an important part of its composition. Kaolins are not
uniform in physical properties but their chemical composition
ranges within narrow limits and good grades contain 37 to 40
percent alumina, 45 to 55 percent silica, 8 to 15 percent ignition
loss, and minor amounts of ferric oxide, titania, alkaline earth
oxides and alkali oxides. Whiteness, both in the dry and fired con-
dition, is an important property in kaolins used in paper fillers
and whiteware and this property requires a low content of iron
compounds. Most kaolins have low plasticity, low dry and fired
strength, low drying and firing shrinkage and high fired porosity.
The notable exception to these characteristic properties is the well-
known plastic kaolin of Florida that is produced in Putnam County
by the Edgar Plastic Kaolin Company and the United Clay Mines
Corporation. This material has physical properties that are inter-
mediate between the ball clays and the more typical kaolins.
The commercial deposits of kaolin in Putnam County consist of
a mixture of sand and clay with the clay content averaging about
18 percent of the material that is mined. This kaolin mixture is
beneficiated by removal of impurities, principally quartz grains
and minor amounts of mica, feldspar, and heavy minerals, through
a series of disintegrating, washing, screening, classification, thick-
ening, filtering and drying operations. Disintegration by hammer
mills and air classification to produce dry pulverized material of
specified particle size complete the milling process.

















Fibrous Types
Chain Structure


Palygorskite Koolinite Mo
Group Group
I I
Polygorskite Koollnite Ml
(Florldin) Halloysite, 2H20 Be
(Attopulgite) Hydroted holloysite,4H20
Sepiolite Nocrite He
Gornierite Dickite So


0



a
Micaceous or Ploty Types Amorphous 0
Loyered Structures Types






ontmorillonite Illite Mixed Layer Allophone
Group Group Group Group
I- I I I
ontmorillonite Illite Anauxite Allophono
dellite Glouconito Chlorite
Nontronite Vermiculite-chlorite
ectorite Koolinite- nontronite
Iponite Montmorillonite-illite

After Grim,1953
Mielenz and King, 1955

Figure 18
Classification of clay minerals.





MINING AND MINERAL RESOURCES


The uses for kaolin may be divided into four general classi-
fications: fillers, whiteware, refractories, and cement. For
paper filler, the physical properties of grit, color, particle size, and
retention determine its suitability. For rubber, where kaolin com-
petes with carbon black and zinc oxide, desirable properties in-
clude uniformity, purity, fineness of particle size, absorption and
dispersion characteristics. For oil cloth and linoleum filler, kaolins
should be white, free of grit, and should slake readily to a smooth
cream or slip and have low oil absorption. For paint where kaolin
is used as a pigment as well as an extender, fineness of grain size
and freedom from grit are essential but the only reliable evalua-
tion test for its use in paint is the endurance of the paint that
extends over a period of years. Kaolins find use as fillers in a num-
ber of other products, textiles and window shades, calcimine, cray-
ons, toilet and tooth powders, soaps, polishing compounds and
matches. Tests and specifications for these uses have not been
established.
Whiteware is a clay product manufactured from a combination
of white burning kaolin and ball clay, feldspar, ground silica or
flint, and other ingredients. The kaolin content of various white-
ware bodies ranges from 10 to 50 percent of the dry weight of the
ingredients and averages about 25 percent. The ball clay content
ranges from 10 to 30 percent; feldspar from 5 to 40 percent; and
flint up to 40 percent. To replace the feldspar, both nepheline
syenite and talc are used as substitutes. The chief types of white-
ware, include pottery, tableware, electrical porcelain, floor and
wall tile, and sanitary ware.
The quantity of kaolin used in the manufacture of refractories
has increased during recent years and this trend probably will
continue because new supplies of high grade fire clays are not being
found. The refractories made from the kaolins of the Coastal
Plain of Georgia, South Carolina and Florida have not been fully
evaluated but for some uses they are comparable with the re-
fractory brick made in Missouri and Pennsylvania. Because the
specifications for kaolin used for refractory raw materials are not
as exacting as those for some ceramic uses and because there is an
increasing demand for firebrick, the utilization of the kaolins of
Florida for this purpose may be considered for the establishment
of a new industry in the State.
Stoneware clays of Jackson, Washington, and other counties in
West Florida are suitable for use as fire clays and are capable of
withstanding temperatures above 2,9000F. The clays found in
the Chipley area that fire to a light buff or cream color were




60 FLORIDA GEOLOGICAL SURVEY-BULLETIN THIRTY-NINE


Figure 19
Dredge of the Edgar Plastic Kaolin Company pit, Edgar, Putnam County.
The overburden is removed by pan scrapers and the clay-sand strata are
recovered by suction dredge.
formerly produced and utilized without beneficiation to make brick.
This product was used for common brick although the p.c.e. (pyro-
metric cone equivalent) was 33. Besides having a high p.c.e., re-
fractory brick must withstand rigid thermal spelling and high-
temperature load tests. Super-duty brick has a p.c.e. of 34 or
higher; high-heat duty refractories 32-33, while intermediate-duty
refractories have a p.c.e. of 31-32. In the cooler portions of in-
dustrial furnaces low-duty refractories that have a p.c.e. of 29
give excellent service.
BENTONITE
The original material that was named bentonite is a greenish-
yellow plastic clay found in the Black Hills area of Wyoming and
South Dakota. The name implies neither an exact mineralogical
composition nor definite physical or chemical properties. Clays
found in other localities that had some of the characteristics of
the original bentonite were called bentonite and in this way the
group of clays that consist chiefly of montmorillonite or beidellite
or mixtures of these materials (see fig. 18) became known as ben-
tonite. Two main types are distinguished by physical properties:
(1) the swelling variety absorbs large quantities of water, up to





MINING AND MINERAL RESOURCES


5 times its weight or 15 times its volume and remains in suspen-
sion when dispersed in water; (2) the nonswelling variety that
absorbs only a moderate amount of water, and settles rapidly from
water dispersions. The swelling bentonites characteristically have
sodium as an exchangeable base, while the nonswelling varieties
have calcium. The sodium bentonites are preferred for drilling
muds and the calcium bentonites are used in oil refining. Both
varieties find use as the bond in manufactured molding sands.
The suitability of bentonites for commercial uses depends upon
physical characteristics and chemical analyses are of little value.
The calcium bentonites that are produced chiefly in Mississippi are
highly adsorbent when activated with acids and compete with
fuller's earth in the oil refining industry. Several bentonite locali-
ties are known in West Florida, particularly in Jackson County,
but deposits of sufficient tonnage to warrant commercial develop-
ment have not been found and are not indicated.
FULLER'S EARTH

General properties: Fuller's earth is an inexact term applied to
certain clays that have a marked ability to adsorb coloring ma-
terials from oils of animal, vegetable and mineral origin. Many
clays have this adsorbing power to a slight or very limited degree
and certain other clays, chiefly bentonites, as well as other min-
erals, such as bauxite, can be made highly adsorbent by activation
with acids or alkalies, but the term fuller's earth is generally re-
served for clays that are naturally highly adsorptive. In most
fuller's earths and practically all activable clays, montmorillonite
is a dominant mineral, No definite clay mineral or group is im-
plied in the name fuller's earth and the distinction between fuller's
earth and other clays that have more or less bleaching power is
not sharply drawn. The name as generally used has no generic or
mineralogical significance. The fuller's earth that is produced in
the Florida-Georgia district contains the clay mineral palygorskite
("floridin" or "attapulgite"). The name "attapulgite" was first
used (Grim 1942) in 1935 by DeLapparent to apply to a hydrous
aluminum magnesium silicate found in the fuller's earth from At-
tapulgus, Georgia, and Quincy, Florida, even though this material
had been called "floridin" since 1910. An essential component of
its structure, determined by Bradley in 1940, is that the silica
chains of the molecule are arranged similar to those of the amphi-
bole minerals. The fibrous nature of the lath-like crystals of "atta-
pulgite" is apparent under magnifications reached by the electron
microscope. The ideal formula, [ (OH2) (OH) 2MgsSi8020 4H20],





62 FLORIDA GEOLOGICAL SURVEY-BULLETIN THIRTY-NINE

contains no aluminum but there is considerable replacement of the
magnesium by aluminum. Buehrer (1955) has shown by X-ray
diffraction analysis that the main clay mineral in the deposits of
"attapulgite" in the Florida-Georgia fuller's earth district is paly-
gorskite, a valid mineral name of long standing. Palygorskite has
a very similar, if not identical chemical composition and X-ray
diffraction pattern to attapulgite, consequently the name "paly-
gorskite" has precedence over "attapulgite."
In most fuller's earths and bentonites, the clay mineral mont-
morillonite is the dominant constituent. The fuller's earth pro-
duced in the Florida-Georgia district contains as an essential con-
stituent palygorskite ("floridin" or "attapulgite"), the physical
and chemical properties of which produce a fuller's earth that has
many superior properties.
The use of fuller's earth for its adsorbent properties dates
from ancient times and the clay-like earthy substance obtained its
name because the clay was used by fullers to full, or remove,
grease and fat from woolen cloth. The first discovery in the
United States of clay suitable for fuller's earth was made at
Quincy, Florida, in 1893, where the earth has been produced com-
mercially since 1895. Extensive deposits of the clay occur in
Gadsden County, Florida, and in Decatur County, Georgia, where
mining began in 1907. Since 1896, the details of mining and pro-
duction have appeared annually in publications of the U. S. Geo-
logical Survey and the U. S. Bureau of Mines. From these reports,
it may be seen that for many years the United States has been
the world's leading producer and consumer, of fuller's earth. Do-
mestic production increased steadily to a peak of over 335,000 tons
in 1930, almost parallel to the increase in petroleum production.
During the next decade, the industry experienced a sharp decline
in production to a low of about 146,000 tons in 1940. This decline
is attributed to changes in petroleum refining methods, increased
use of colored gasolines and the substitution of activated benton-
ites, activated bauxite, and synthetic magnesium silicate in the
mineral oil bleaching industry.
With reference to table 6, which shows the annual production
of fuller's earth in the Florida-Georgia district and in the United
States for the years 1940 to 1955 inclusive, it may be seen that
the combined output from Florida and Georgia constituted in 1940,
about 54 percent of the quantity and 62 percent of the value of the
total United States production; in 1955 these states produced 67
percent of the quantity and 78 percent of the value of the fuller's
earth production.





MINING AND MINERAL RESOURCES


Table 6

Production and Value of Fuller's Earth 1940-1955

Florida-Georgia U. S. Total
Year Short Tons Value Short Tons Value

1940 79,898 $ 917,365 146,568 $1,471,083
1941 91,925 1,075,318 207,446 2,111,674
1942 83,007 1,091,062 204,244 2,139,670
1943 105,647 1,444,936 271,667 2,664,027
1944 128,654 1,833,682 294,737 3,297,064
1945 134,401 1,939,035 296,368 3,463,913
1946 144,214 2,100,652 298,752 3,702,993
1947 168,557 2,699,660 329,068 4,660,614
1948 188,014 3,224,169 342,081 5,273,851
1949 181,933 3,194,551 320,906 5,199,642
1950 247,390 4,273,890 396,025 6,504,733
1951 299,071 5,258,330 483,623 8,131,761
1952 270,261 4,829,552 422,853 6,875,483
1953 271,187 5,093,501 435,837 7,614,759
1954 263,571 5,244,591 376,321 6,861,603
1955 Est. 250,000 Est.5,980,000 369,719 7,620,319
Data-U.S. Bureau of Mines

In recent years, all of the Florida production has come from
mines located in Gadsden County, but fuller's earth was formerly
mined in Marion and Manatee counties. The abandoned pits in
sec. 34, T. 13 S., R. 20 E., Marion County, and sec. 10, T. 34 S., R. 18
E., Manatee County, mark the sites of these operations. The clay
mineral found at the Marion County locality is montmorillonite
while the clay minerals found at the Manatee County locality con-
sist of a mixture of montmorillonite and palygorskite ("floridin"
or "attapulgite"). Recent studies of the clay mineral composition
of the sediments in the land-pebble phosphate district have re-
ported palygorskite ("attapulgite") as a component of the over-
burden and of the matrix. The Florida-Georgia fuller's earth dis-
trict includes portions of Gadsden County, Florida, and Decatur
and Grady counties, Georgia, and the locations of active mines
and plants are shown on the sketch map, figure 20.
Florida-Georgia District: Exposed at the surface throughout the
district, the Hawthorn formation is nearly horizontal and attains
a thickness in excess of 200 feet.' The City of Quincy water well
penetrated 210 feet of sediment assigned to this formation. There
are oth continental and marine fossils above and below the fuller's
earh beds, indicating that the sediments were laid down during
a ransitional period, probably in shallow fresh water along a sea
coast. Throughout the district, the Hawthorn formation contains
lenses of fuller's earth and of dolomitic limestone but, for the most





64 FLORIDA GEOLOGICAL SURVEY-BULLETIN THIRTY-NINE

part, consists of poorly sorted, coarse to fine-grained argillaceous
sands. In a typical section as exposed in the mines, there are two
beds of fuller's earth, each two to eight feet thick, separated by a
bed of gray, clayey sand, which is usually less than five feet in
thickness. The sandy stratum between the fuller's earth beds yields
manatee and other vertebrate fossils, as well as Pectens, oysters
and fossil wood.
The overlying sandy clays that make up the remaining portion
of the section generally contain lumps and pebbles of fuller's earth
in the base and grade upward into a brown quartz soil zone at the
top. In some areas, the upper clay bed is too thin to be mined or
lenses of sand may be present in it. Under such conditions, the
clay is removed with the overburden.
Mining practice consists of removal of overburden by dragline,
bulldozer, or pan scrapers, depending on the depth of the over-
burden and the distance that it must be moved. The clay bed is
carefully cleaned and the dragline loads the clay on trucks for
removal to the processing plants. Very little blasting is necessary
in the removal of the overburden but the clayey sand layer be-
tween the beds of fuller's earth may require blasting to loosen it
sufficiently for removal by the dragline.
Preparation: In the preparation of fuller's earth for market,
three processing treatments are utilized to control the properties of
fuller's earth; these are extrusion, drying, and milling. The crude
fuller's earth is crushed, kneaded with water in a pug mill, and
then fed through an auger-type extruder in which the plastic
earth is forced through openings of about three-quarters of an incn
in diameter to form rods of fuller's earth. In this extrusion pro-
cess, laminations in the earth are disrupted, the apparent density
of the material is lowered, and both the porosity and the decolor-
izing capacity of the product are increased considerably. The
drying temperatures have a marked effect on the characteristics of
plasticity, dehydrating capacity, and decolorizing capacity. For
the colloidal product used as drilling mud, it is necessary to dry
the clay at relatively low temperatures (below 250 F) in order
that the earth will disperse readily in water; in order to develop
the maximum absorptive capacity, a higher drying temperature is
required. Absorbent grades of fuller's earth for use on floors are
dried at temperatures above 7000 F to prevent the product from
muddingg up" in water. The milling process consists of a series
of crushing, grinding and sifting operations to produce granules
and powders. The grades produced range from granules of 16 to
30 mesh to powders 90 to 95 percent finer than 325 mesh.















I WI* UT COUNTY



SMIESO










LEGEND

** A MINERALS AND CHEMICALS CORP OF AMERICA '
+ FS. VIFLORIDIN GO.
4" z
















MINE

Figure 2b

Location of the principal mines and plants in the Florida-Georgia fuller's earth district.
Location of the principal mines and plants in the Florida-Georgia fuller's earth district.





66 FLORIDA GEOLOGICAL SURVEY-BULLETIN THIRTY-NINE

.




















Figure 21
The Floridin Company's Frank Smith No. 2 mine showing the dragline with
a 1%-yard bucket used to remove overburden from the clay bed. The area to
the right has been leveled by pan scrapers.

Uses: Decolorizing and refining mineral oil and vegetable oil
were formerly the main uses for fuller's earth, and as late as 1943
more than 87 percent of the production was consumed in these uses.
For many years, fuller's earth has been on the market for use in
rotary drilling muds, but advances made in well drilling techniques
in 1943 and 1944 resulted in increased gtnnages to be used by the
petroleum exploration industry. In 1955, 13 percent of the pro-
duction was sold for drilling mud. Beginning in 1943, granular
grades of fuller's earth were first marketed for absorbent use and
this product was an immediate success. This cleaning agent finds
use in service stations, factories, machine shops, bakeries, and
other establishments where oil and grease spills are likely to occur.
Measured in terms of tonnage consumed annually, these absorbent
uses have become the most important market for fuller's earth
and in 1955, 37 percent of the production was consumed in these
uses. In 1946, the large adsorption capacity of pulverized fuller's
earth was utilized in processing the newer organic insecticides and
it has become an important carrier of insecticides and fungicides.
In 1955, these uses ranked second in terms of tonnage and ac-
counted for 25 percent of the production. The quantity of fuller's





MINING AND MINERAL RESOURCES


Figure 22
Chesebrough mine of the Floridin Company, located south of Quincy, Florida,
showing dragline with 3-yard bucket and 90-foot boom used to remove 40 feet
of overburden and to load trucks. In the portion of the mine under develop-
ment, the clay bed reaches a thickness of 16 feet.

earth that was utilized in filtering and decolorizing mineral oils
and vegetable oils decreased to 16 percent of the 1955 production.
MISCELLANEOUS CLAYS

Miscellaneous clays include those that are frequently designated
as surface clays or common clays and the clay products com-
-panies that utilize them usually mine and process them. Products
that are made from common clays include building bricks, sewer
pipe and roofing tile, as well as lightweight aggregate and portland
cement. Throughout the country, production of common brick,
hollow tile and roofing tile has not kept pace with industrial
growth. Utilization of Florida clays for these materials has de-
creased and no modern clay brick plants are located in the State.
Locality and firing test data on a number of clay deposits are in-
cluded in Florida Geological Survey Information Circular No. 2,
and in Florida Geological Survey Fifteenth Annual Report.
The only clay that is utilized as an ingredient of portland ce-
ment is mined in Citrus County by the General Portland Cement
Company, Florida Portland Cement Division. For this purpose,




68 FLORIDA GEOLOGICAL SURVEY-BULLETIN THIRTY-NINE

no special requirements are necessary but the clay must provide
the alumina and silica for the cement formula.
Clays that are suitable for lightweight aggregate production
must be naturally bloating clays or must have ingredients added
to them before processing to produce bloating. At the present
time, no lightweight aggregate manufacturing plant that utilizes
Florida clay is located in the State. A plant near Ellenton, Mana-
tee County, formerly produced aggregate from a clay which had
previously been used to manufacture fuller's earth. This plant,
abandoned and dismantled soon after World War II, produced the
aggregate called "nodulite" which was used in the manufacture of
concrete ships and barges at Tampa. During recent years, the
U. S. Bureau of Mines, working in cooperation with the Florida
Geological Survey and others, have conducted a search to find
suitable material in Florida for making lightweight aggregate.
Tests have been conducted on the washery slimes produced in the
processing of land-pebble phosphate. While an acceptable aggre-
gate was made, the cost of drying the slimes was so great that
commercial utilization was prohibitive. Tests thus far conducted
on clays from localities throughout the northern portion of the
State have failed to indicate a natural bloating clay that is suitable
for aggregate manufacture.

DIATOMITE

Diatomite or diatomaceous earth is a valuable earthy material
that is composed of minute particles of opaline silica, the 'ossil
remains of microscopic aquatic plants related to algae. This ma-
terial is essentially hydrous amorphous silica and pure varieties
are chalk-like in appearance, light in weight, porous and fr/able.
When pure and dry, its apparent density is less than one so that
it will float on water until saturation overcomes its bouyancy.
More than 10,000 varieties of diatoms have been classified and
these occur in every conceivable shape.
The acceptance of diatomite by consumers depends on the
physical structure, size, shape, and purity of the material. The
1954 output was utilized in the following ways: 51 percent in
filtration of sugar, beverages, water, pharmaceuticals, oils and
other liquids; 29 percent as a filler in rubber, paper, asphalt,
plastics, explosives, insecticides, paints and other products; 8 per-
cent in the manufacture of insulation, and 3 percent in abrasives.
Miscellaneous uses such as absorbents, catalyst carriers, as poz-
zolanic material in concrete, and in ceramics. In recent years,





MINING AND MINERAL RESOURCES


diatomite produced in the United States exceeded 300,000 short
tons per year, valued at the mines at nearly $10,000,000.
Uniformity in grade and high quality standards are maintained
in the industry, except when the diatomite is supplied from local
sources or for such purposes as concrete admixture. In 1954, Cali-
fornia led all states in production, followed by New Mexico, Ne-
vada, Oregon, Washington and Arizona. Diatomite occurs in
three types of deposits: (1) ancient marine beds, such as the
California deposits that cover several square miles and are 700
feet thick in places; (2) deposits adjacent to rivers and lakes
that contain fresh-water diatoms; and (3) deposits in lakes and
swamps where deposition and accumulation is still going on. De-
posits of the second and third types are found in Florida and these
contain more or less organic matter in the form of muck and peat.
From such wet, bog-type deposits, recovery by dredges, pumps or
dragline would be required and preparation would include de-
watering by draining or pressing, drying on racks or in kilns,
calcining, grinding and air classification. For nearly all uses free-
dom from impurity is important and in filtration uses the type,
size, shape of the diatoms as well as the absence of broken and
very small specimens are important factors that influence the
rate of flow and clarity of the filtrate. Careful grading of the
diatoms to produce a uniform product that consists of the most
advantageous shapes and sizes is necessary to obtain a superior
filter aid.
Diatomite has many industrial applications and products that
are filtered with the aid of diatomite include acids and chemicals,
polluted waters, petroleum compounds, varnishes, shellacs, waxes,
resins, gum solutions, sugar solutions, vegetable oils, animal fats,
gelatins and many others. As a mineral filler, diatomite adds bulk
strength, absorptiveness and other desirable physical properties to
asphalt products, rubber, and paper products, plastics, insecticides,
explosives and other chemicals. As an insulating material, diat-
omite is used in industrial furnaces and kilns for heat and in
building construction for both heat and sound insulation. Diat-
omite is used as an abrasive, as a support and carrier for cata-
lysts in chemical processes, as a source of silica in ceramic bodies
and glazes and in the manufacture of "water glass," or sodium sili-
cate. Its characteristic to absorb up to 200 percent of its weight
of water is made use of in desiccants and absorbents.
The problem of utilizing the relatively small deposits that exist
in Florida, and in other eastern states, continues to attract the at-
tention of possible producers because the largest markets are





70 FLORIDA GEOLOGICAL SURVEY-BULLETIN THIRTY-NINE

located in the eastern states, the huge reserves of easily mined and
processed diatomite that exist in the Pacific Coast states, and
Nevada, are more than ample to supply the anticipated expanding
needs for diatomite. It is possible, however, that some of the de-
posits of Florida, particularly those in Polk County, could be pro-
duced commercially as a by-product. In part of the land-pebble
phosphate district, diatomaceous muck and peat occur in the
overburden above the phosphate ore bed. The economics of pro-
ducing diatomite from this material that would otherwise be re-
moved and discarded as overburden is under study by at least
one of the major phosphate producers.
A review of the diatomaceous earth localities in Florida is in-
cluded in Florida Geological Survey Bulletin No. 30, The Peat De-
posits of Florida.

LIME

Lime is a calcium oxide (CaO), or the combined oxides of cal-
cium and magnesium (Ca-MgO) and does not occur in nature.
It is a product manufactured from limestone (CaCO) or dolomite
[CaMg(CO,) 2] by the process of calcination, in which carbon di-
oxide (CO2) is driven off at moderately high temperatures. For
most uses, high calcium and dolomitic limes are interchangeable.
Lime has numerous uses and the principal groups of uses include:
(1) industrial and chemical applications, such as metallurgy, alka-
lies (ammonium, potassium, and sodium compounds), paper mills,
calcium carbide and cyanamide, water purification and glass; (2)
building materials such as finishing lime and mason's lime and
mortar; (3) agricultural lime for soil improvement, and (4) re-
fractory lime, or dead-burned dolomite, is calcined at high tem-
peratures to produce a product that has a high melting pointand
is suitable for furnace linings. Within the lime industry in the
United States, there is a long and continued trend toward fewer
and larger plants. The number of lime plants has decreased from
1,073 in 1910, to 336 in 1930, to 154 in 1954, when more than 60
percent of the total output was produced by 26 plants. Approxi-
mately six percent of the annual production of limestone and dolo-
mite is consumed by the lime manufacturing industry.
The only commercial lime producer in Florida is the Dixie Lime
Products Company, located at Reddick, Marion County. That
company has nine shaft kilns and one hydrator and produces high
calcium quicklime and hydrated lime. Both wood and fuel oil are
utilized to burn the limestone and the capacity of the plant is





MINING AND MINERAL RESOURCES


approximately 12,000 tons of quicklime annually. The only other
lime producer in Florida is the by-product production from the
Hialeah water softening plant that is operated by the City of
Miami. In this water treatment plant, the calcium carbonate that
is removed from the water is recalcined in an oil fired rotary kiln
to produce quicklime. Between 10 and 15 percent more quicklime
is produced than is utilized in the water treatment process and
this excess is sold to other municipal water treatment plants in
Florida. The rotary kiln in use has an annual capacity of about
26,000 tons of quicklime.
The apparent consumption of lime in Florida as reported by
the U. S. Bureau of Mines indicates that the State is deficient in
lime production and that considerable quantities are purchased
from other states. During recent years, data on the production
of lime within the State have not been made available for publi-
cation, nevertheless, the capacity of the existing plants is about
one-third the tonnage of lime that is consumed within the State,
see table 7. Because there are considerable variations in the phys-
ical and chemical properties of limes, specifications for a particu-
lar use or industry may require shipments from distant points.
Not only do the physical and chemical characteristics of the lime-
stone but also the rate of heating, the temperature, and other kiln
factors influence the properties of the finished product.

Table 7
Apparent Consumption of Lime (Both Quicklime and
Hydrated Lime) Sold or Used in Florida
Year Quantity
Short Tons
1945 67,586
1946 77,103
1947 80,070
1948 103,853
1949 100,427
1950 99,559
1951 107,005
1952 117,180
1953 139,720

Because fragmentation of the limestone in the quarrying pro-
cess produces small sizes of rock that are not suitable for kiln feed,
most lime companies also produce agricultural limestone and
crushed stone for concrete aggregate. By use of modern shaft
kilns, not more than three-quarters of the rock that is quarried is
suitable for loading into the kilns. In order to manufacture 100
tons of lime per day, it would be necessary to quarry about 250





72 FLORIDA GEOLOGICAL SURVEY-BULLETIN THIRTY-NINE

tons of rock and the disposal of the finer sizes of rock becomes an
important factor in the success of the operation. The rotary kiln
makes possible the utilization of finer materials but the cost of
such equipment is considerably more. The design of calciners of
the vertical type has undergone changes in recent years to alloW
use of smaller sizes of rock. The recovery and utilization of the
carbon dioxide gas that is driven off in the calcining process is a
serious problem in the industry because nearly one-half the weight
of the kiln feed is lost as this gas is dissipated into the air.
By far the largest quantity of lime enters chemical and indus-
trial processes and new lime plants may be expected in Florida
with the establishment of new lime-consuming industries. The
leading volume consuming uses of lime include metallurgical ap-
plications as a flux in steel manufacture, in nonferrous smelting,
and in ore concentration; in the manufacture of alkalies (ammon-
ium, potassium, and sodium compounds); in paper mills; water
purification; in calcium carbide and cyanamide manufacture; in
glassworks, and in sewage and industrial waste treatment.

FLUORINE

The element fluorine occurs in minute quantities in a large
number of rocks and minerals but large quantities of the element
are found in only two commercial minerals, fluorite and cryolite,
both of which are distinctly uncommon. A small area located along
the Ohio River in southern Illinois and western Kentucky processes
about 80 percent of the fluorite while several smaller deposits in
Colorado, New Mexico, and other western states contribute to the
quantity mined. In the United States, fluorite, or fluorspar, is the
only fluorine mineral of commercial importance; and the only other
fluorine mineral of commerce, cryolite, is obtained from only one
locality situated in Greenland. In recent years, the domestic pro-
duction of fluorite amounted to about two-thirds of the-quantity
used in this country but current trends indicate imports will in-
crease to supply over one-half the quantity used by United States
industry by 1965. Fluorine compounds are used in the production
of aluminum, high-octane gasoline, Freon refrigerants, and in the
manufacture of steel, glass, and enamels.
The reserves of fluorine contained in the fluorapatite, the min-
eral that constitutes the bulk of the cellophane or phosphate rock
produced in the land-pebble field of Polk and Hillsborough coun-
ties, are very large, Phosphate rock contains 1 to 3 percent fluorine
which may be recovered as a by-product in the manufacture of





MINING AND MINERAL RESOURCES


superphosphate fertilizer. This by-product is not limited to plants
located in Florida, and is produced wherever superphosphate plants
are located. The Bureau of Mines reports show that in 1955, there
were 19 plants reporting production of fluorine by-products. Only
two of these were located in Florida. In the acidulation process
for fertilizer manufacture, phosphate rock is treated with sulfuric
acid and about one-half of the fluorine is evolved as a toxic gaseous
mixture which may be captured in water absorption towers or
in a bed of lump limestone. A large potential source of fluorine
chemicals exists in the phosphate industry, although recovery of
this material is practiced only to a small extent at the present
time. The development of competitive methods for the recovery
of fluorine compounds from phosphate rock not only will relieve
a possible shortage of fluorite but also will provide a market for
a toxic gas that has caused much concern to the phosphate in-
dustry. New techniques to improve the present methods for de-
fluorination of phosphate rock and to produce fluorine by-products
that have industrial value are actively being sought by the research
programs conducted by the industry.

GYPSUM

Measured by production and sale of gypsum products, the gyp-
sum industry is one of the most important in the nonmetallic field.
Although the United States has huge reserves of gypsum, con-
siderable tonnages of crude ore are imported for use in consuming
areas that are situated in the Atlantic coastal states. Much of the
raw gypsum that is consumed in Florida by the gypsum products
plant at Jacksonville and by the portland cement plants, is im-
ported from Nova Scotia.
Gypsum hydrouss calcium sulfate) is a common mineral and
the large or most important deposits of the material are believed
to have been formed by the evaporation of sea water. Many gyp-
sum beds were originally deposited as anhydrite (anhydrous cal-
cium sulfate) which was changed to gypsum in alteration pro-
cesses associated with weathering. The minor occurrences of gyp-
sum in Florida, particularly the clear or slightly stained crystals,
are associated with the sulfur waters which have encountered shell
or limestone fragments. Several gypsum localities are known in
Florida but none has enough indicated tonnage to be worked. The
earliest report of gypsum in the State was published in 1899 in
the U. S. Geological Survey's Twentieth Annual Report (U.S.G.S.
20th Ann. Rept., part 6, cont. p. 662-663, 1899) and records a





74 FLORIDA GEOLOGICAL SURVEY-BULLETIN THIRTY-NINE

gypsite deposit in the E1/2, sec. 23, T. 20 S., R. 21 E., Sumter Coun-
ty. This material was described as a clay-like substance that hard-
ens upon exposure to air; and that the surface deposits occurred
as hummocks from three to six feet high. Gypsum crystals are
found in the alluvium of the St. Johns River valley, and at the
locality three miles east of Christmas, Orange County, where
scattered gypsum crystals up to three-quarters of an inch in length
are present at a depth of four feet. Scattered crystals of gypsum
have also been obtained from the St. Johns River valley at Sanford,
Seminole County.
In addition to natural gypsum, a calcium sulfate waste product
is obtained in the preparation of superphosphate fertilizer. This
"gypsum" could be recovered, however, from a commercial point
of view; the quantity of such material is rather small. The possi-
bility of a by-product use for this "gypsum" presents an interesting
problem in industrial chemistry for its conversion into ammonium
sulfate fertilizer, or some other industrial chemical.

RADIOACTIVITY SURVEYS

Airborne radioactivity surveys have been made in Florida by
the U. S. Geological Survey during their investigations of the
uranium and thorium content of the surface formations of the
State. These investigations were carried out at the request of the
Division of Raw Materials, Atomic Energy Commission. The areas
of the State that were covered by these surveys are shown on
figure 23, and the index numbers shown on the map correspond to
the following government publications:

REPORTS CONTAINING RADIOACTIVITY DATA FOR
AREAS IN FLORIDA

(Refer to numbered localities on figure 23)
Index
No.
1. Moxham, R. M., and Johnson, R. W., Airborne Radioactivity Survey of
Parts of the Atlantic Ocean Beach, Virginia to Florida, U. S. G. S.,
Trace Elements Memorandum Report 644, June 1953.
2. Meuschke, J. L., Moxham, R. M., and Bortner, T. E., Airborne Radio-
activity Survey of the Gulf of Mexico Beach between Sanibel Island
and Caladesi Island, Florida, U. S. G. S., Trace Elements Memorandum
Report 678, November 1953.
S3. Moxham, R. M., Airborne Radioactivity Surveys for Phosphate in
Florida, U. S. G. S., Trace Elements Investigations Report 387, August
1953.
Moxham, R. M., Airborne Radioactivity Surveys for Phosphate in
Florida, U. S. G. S., Geological Circular 230, 1954.





MINING AND MINERAL RESOURCES


INDEX TO
RADIOACTIVITY SURVEYS
IN
FLORIDA


'I'


Figure 23
Index to reports on radioactivity surveys in Florida.
4. Cathcart, J. B., Drilling of Airborne Radioactivity Anomalies in Flor-
ida, Georgia, and South Carolina-1954, U. S. G. S., Open file report
released September 30, 1954.
5. Moxham, R. M., Airborne Radioactivity Survey in the Folkston Area,
Charlton County, Georgia, and Nassau County, Florida, U. S. G. S.
Geophysical Investigations Map GP 119, 1954.
6. Meuschke, J. L., Airborne Radioactivity Survey of the Fort Myers
Area, Charlotte and Lee Counties, Florida, U. S. G. S., Geophysical
Investigations Map GP 121, 1954.
7. Meuschke, J. L., Airborne Radioactivity Survey of the Gardner Area,
DeSoto, Hardee, Manatee, and Sarasota Counties, Florida, U. S. G. S.,
Geophysical Investigations Map GP 122, 1955.
8. Search for and Geology of Radioactive Deposits, Semiannual Progress
Report, December 1, 1952 to May 31, 1953, U. S. G. S., Trace Elements
Investigations Report 330, June 1953.
9. Geologic Investigations of Radioactive Deposits, Semiannual Progress
Report, June 1 to November 30, 1953, U. S. G. S., Trace Elements In-
vestigations Report 390, December 1953.
10. Geologic Investigations of Radioactive Deposits, Semiannual Progress
Report, December 1, 1954 to May 31, 1955, U. S. G. S., Trace Elements
Investigations Report 540, June 1955.





76 FLORIDA GEOLOGICAL SURVEY-BULLETIN THIRTY-NINE

11. Geologic Investigations of Radioactive Deposits, Semiannual Progress
Report, December 1, 1953 to May 31, 1954, U. S. G. S., Trace Elements
Investigations Report 440, June 1954.
12.(a) Cathcart, J. B., and others, The Geology of the Florida Land-Pebble
Phosphate Deposits, U. S. G. S., Open file report released March 1953.
(b) McKelvey, V. E., and others, Domestic Phosphate Deposits,
U. S. G. S., Open file report released March 1953.
13. Contributions to the Geology of Uranium and Thorium, U. S. G. S.
Professional Paper 300, 1956, 739 pp.
The following chapters deal with Florida geology:
(a) Natural occurrence of uranium in the United States-a summary,
by Hobart E. Stocking and Lincoln R. Page, pp. 5-12.
(b) Distribution and occurrence of uranium in the calcium phosphate
zone of the land-pebble phosphate district of Florida, by James B.
Cathcart, pp. 489-494.
(c) The aluminum phosphate zone of the Bone Valley formation, Florida,
and its uranium deposits, by Zalman S. Altschuler and others, pp. 495-
504.
(d) Geology of thorium deposits in the United States, by William S.
Twenhofel and Katherine L. Buck, pp. 559-566.
(e) Mineralogy of thorium, by Clifford Frondel, pp. 567-580.
(f) Monazite in southeastern United States, by William C. Overstreet
and others, pp. 597-604.

LIGHTWEIGHT AGGREGATES

GENERAL STATEMENT
Lightweight mineral aggregates, when used with portland ce-
ment, produce concrete that has a unit weight of less than 120
pounds per cubic foot. There are three principal types of light-
weight aggregates that are employed according to the kind -r use
of the concrete. In structural concrete, for use in monolithic con-
crete for buildings, floors, roofs, partitions, bridge decks, etc., the
main purpose is to reduce weight to economize on the design. For
such purposes, the workability and strength characteristics of the
lightweight concrete should be similar to ordinary concrete but
the unit weight may range from 90 to 120 pounds per cub'c foot.
In masonry uses, the concrete is usually precast or fabricate into
machine-made units for walls and partitions that may be either
load-bearing or nonload-bearing. For these uses, good insulating
and sound-deadening characteristics are desirable in addition to
lightweight and moderate strength. The range in unit weight for
such concrete varies from 75 to 95 pounds per cubic foot. In insu-
lation and fill uses, as in monolithic lightweight concrete for par-
titions, walls, and floors, and roof fills, precast units are employed
that have little strength but lightness and insulation values are
desired. For such uses, the unit weight of the concrete varies from
35 to 75 pounds per cubic foot.





MINING AND MINERAL RESOURCES


The classification of lightweight aggregates is based on source
of the material as either natural or artificial. Artificial aggregates
may be by-products or specially manufactured. The most common
natural lightweight aggregates are pumice, other volcanic rocks
like scoria and volcanic cinders. By-product aggregates include
cinders and coke while special manufactured aggregates are pro-
duced from clay, shale, slate, furnace slag, perlite, vermiculite and
other materials. These materials when processed develop a porous,
vesicular, or exfoliated structure that results in a lightweight prod-
uct. The most important properties to users of lightweight con-
crete are unit weight, strength, durability, thermal conductivity,
fire resistance, sound absorption, water absorption, shrinkage, and
nailability. These characteristics vary with the type of aggregate,
and the shape, size, and surface texture of the individual particles.
No one aggregate can meet all of the various requirements and
each has characteristics that suit the material for particular uses.
Because lightweight aggregates are usually more expensive than
ordinary aggregates, justification for their use involves considera-
tion of the advantages offered with regard to weight reduction,
thermal insulation, fireproofing, nailability, as well as savings in
structural design.
PERLITE AND VERMICULITE
Expanded perlite has found wide acceptance in the construc-
tion industry where it substitutes for sand in plaster and concrete.
Perlite is a rock of volcanic origin containing silica and combined
water and other gases which when heated to its softening tempera-
tures will expand 4 to 20 or more times in volume. The resulting
lightweight, glassy, white particles are used to make lightweight
plasters and concretes as well as for loose-fill insulation. The
quantity of perlite sold is limited by the furnace capacity available
and an increase in number of plants may be expected in Florida.
Most of the crude perlite is mined in Nevada, New Mexico, and
Colorado where it is shipped throughout the United States. In
1955, there were 91 perlite processing plants located in the United
States and three of these were situated in Florida, one each at
Jacksonville, Vero Beach, and Hialeah.
Approximately three-quarters of the production of expanded
perlite is used as an aggregate in gypsum plaster where it replaces
sand and the resulting plaster is lightweight, and has good thermal,
acoustical, and fireproofing properties. Perlite is also used in con-
crete to make poured roof decks and floors, and in prefabricated
units of various kinds. Many minor uses have extended the





78 FLORIDA GEOLOGICAL SURVEY-BULLETIN THIRTY-NINE

applications of this material as a filler for rubber, soap, paints,
plastics, and resins, as well as a substitute for diatomaceous earth
in filtration beds. Perlite is such a new material that all of its po-
tential markets are not yet developed.
Vermiculite is a micaceous material that is associated with ig-
neous and metamorphic rocks. No deposits of this material are
found in Florida but two companies operate plants in Jacksonville,
Tampa, and Boca Raton to process crude vermiculite into a light-
weight, exfoliated material that is used for insulation, lightweight
aggregate in plaster, and for a soil conditioner. The raw material
that is used by the Florida plants is obtained from deposits located
in Montana, South Carolina, and South Africa.
SLAG AND PUMICE
Slag production in the State is a by-product of the electric
furnace production of phosphorus. In this process, the molten slag
from the furnace is chilled with water. If the molten material is
immersed in water, a granular, glassy product is formed; if a
water spray is used, the molten material expands into a cellular
lump product that is crushed and screened. Slag is produced at
Tarpon Springs by the Victor Chemical Works; at Pierce by the
American Agricultural Chemical Company; and at Nichols by the
Virginia-Carolina Chemical Corporation. The granular, glassy
product finds use in road building whereas the expanded material
is used as aggregate in making lightweight concrete products.
The slag-producing industries of Florida do not furnish suffi-
cient volume to satisfy the demand for lightweight aggregates by
the concrete products companies of the State. Slags and expanded
shale aggregates are shipped into the State from Alabama, Georgia
and Tennessee. The cement products industries in the West Palm
Beach and Miami areas utilize pumice, volcanic cinder and scoria
imported from Greece.
EXPANDED CLAY
In order to develop a source of lightweight aggregate within
the State, the Florida Geological Survey working in cooperation
with the U. S. Bureau of Mines, has collected clay samples from a
number of localities for testing and determination of the bloating
or expansion characteristics. These tests have shown that most
of the clays are too refractory for commercial utilization in the
production of lightweight aggregate. Based on the data listed in
table 8, the most promising clay deposits are situated in Clay,
Citrus, and Volusia counties.





MINING AND MINERAL RESOURCES 79

Lightweight aggregate can be produced from clay by two
methods-the rotary kiln and sintering processes. The rotary kiln
is similar to that used by the cement industry and the maximum
temperature utilized is usually within the range 1,9000 to 2,100F.
Most clays probably require pelletizing before firing and this can
be done by means of a horizontal drum pelletizer, an extrusion ma-
chine, or any apparatus where the clay can be mixed with a small
quantity of water and be formed into small pellets. If the clay
pellets agglomerate in the kiln, the discharge must be crushed to
give the desired aggregate size. In the sintering process, the clay
is mixed with from 5 to 10 percent coal, coke, or other fuel and
pelletized. The mixture is fed into either a traveling grate, or a
rotating hearth sintering machine where the charge is ignited and

Table 8

Lightweight Aggregate Test Data from Selected Localities in Florida.
Test Determinations by the U. S. Bureau of Mines

Sample No. Needs
and Range of Sticking Bloating Ex-
County & Locality Thickness Bloat OF Temp. oF Quality trusion

Alachua
Road cut on State 0-273 2100-2200 2200 Good No
Hwy. 26, sec. 4, 0-274 2100-2200 2200 Good No
T. 10 S., R. 19 E. 6% ft. be-
low 5 ft. of
overburden
Clay
Auger sample 0-241 2100-2300 2300 Good No
near old brick 2 ft.
plant, sec. 6,
T. 5 S., R. 24 E.
Citrus
Channel sample 0-229 2000-2300 2300 Excellent No
from General 15 to 20 ft.
Portland Cement
Co.'s pit, sec. 3,
T. 21 S., R. 19 E.
Marion
Clay exposed in 0-266 2000-2200 2000 Good No
abandoned fuller's 30 ft. of
earth pit, sec. 34, green plas-
T. 13 S., R. 20 E. tic clay be-
low 6 ft.
impure
limestone
Volusia
Auger sample Auger sam- 2000-2300 2300 Excellent No
from sec. 26, pie 12 ft.
T. 19 S., R. 31 E. clay





80 FLORIDA GEOLOGICAL SURVEY-BULLETIN THIRTY-NINE

an induced draft draws the burning zone through the charge. The
quantity of fuel in the clay mixture must be sufficient to heat the
material to the bloating temperature. The product is a sintered
cake that is crushed to the desired aggregate size.
The first lightweight aggregate to be made from Florida ma-
terials was produced at Ellenton, Manatee County, during World
War II. In order to be assured a source of aggregate, the firm of
McCloskey and Company that held a contract with the Maritime
Commission to build 24 self-propelled concrete cargo carriers at
Tampa, purchased land at an abandoned fuller's earth mine and
established a lightweight aggregate plant. This property, situated
in sec. 10, T. 34 S., R. 18 E., was acquired in September 1942 and
aggregate made from fuller's earth was being produced at the
rate of 300 cubic yards per day in June of the following year. The
first concrete barge was launched in July 1943. The aggregate
plant operated for only a relatively short time and after it was
sold in 1947 by the War Assets Administration, the plant was dis-
mantled. The manufactured aggregate was called Nodulite and
consisted of spheres of clay that had a coating of sand or cement.
These spheres were fired in rotary kilns, and the resulting Nodulite
aggregate ranged in diameter from one-eighth inch to one inch
approximately. Concrete made with the aggregate weighed ap-
proximately 112 pounds per cubic foot and developed a crushing
strength at 28 days of 7,000 pounds per square inch.
In 1948, the U. S. Bureau of Mines published a series of tests
that were made on some Florida clays and phosphate washery
slimes to determine bloating characteristics and their possible use
in lightweight aggregate manufacture. These data are listed in
the U. S. Bureau of Mines Report of Investigations 4401, "Pro-
duction of Lightweight Concrete Aggregates from Clays, Shales,
Slates and other Materials." While an excellent aggregate was
made from the phosphate washery slimes, the principal objection
for use of this material is its high water content which reaches
40 percent by weight.

LIMESTONE
DIMENSIONAL STONE
The term "dimensional stone" is applied to slabs or blocks of a
natural stone that are cut or broken into shapes that are suitable
for utilization in buildings or construction. The product may have
rather rough surfaces or may be polished, depending upon its use.
The quarrying of dimensional stone is done with great care in





MINING AND MINERAL RESOURCES


order to produce blocks that are suitable for sawing, splitting,
carving and polishing. In general, stone is difficult to work and is
not adapted to mass production methods. The use of stone for con-
struction began, in the United States, with the earliest settlements
and the coquina found on Anastasia Island has the distinction of
being the first dimensional stone used. The oldest buildings in St.
Augustine were constructed, at least in part, of blocks cut from
the shell limestone known as coquina that makes up a portion of
the Anastasia formation. With the development of the building
industry, stone was replaced by steel as the load-bearing material
and later reinforced concrete replaced stone in structures. Mod-
ern stone buildings have only a thin veneer of stone. Stone is gen-
erally more expensive than concrete, brick and other substitutes;
consequently, it is used primarily in high class construction where
its attributes of permanence, dignity and architectural adaptability
may be displayed. Many factors enter into the suitability of a
particular rock formation for use as a dimensional stone and
pleasing texture and color stability are important considerations.
Research by the industry has developed improved machines and
techniques for fabricating stone and among the improvements are
the diamond saws, the cutting and splitting machines. The
Bradenton Stone Company, Manatee County, produces a variety
of stone products including split-face ashlar, smooth-face ashlar,
flagstone, sills, and coping in a modern plant located at Oneco,
Florida. This company quarries dolomite from a location south-
east of Bradenton, see figure 24, and trucks the large blocks to
the plant at Oneco, figures 25 and 26. The rock formation has been
quarried for many years not only for building stone, which is sold
under the commercial name "travertine," but also for agricultural
stone. It is considered to be a portion of the Hawthorn formation
of Miocene age.
The coralline limestone of the Key Largo formation of Pleisto-
cene age has likewise been quarried for many years for dimensional
stone. Figures 27 and 28, the quarry on Windleys Key, Monroe
County, produces large blocks that are trucked to Miami for cut-
ting into dimensional stone by the Keystone Art Company. The
porous or open texture of the coralline limestone gives a very
pleasing appearance but it makes the rock more suitable for in-
terior work than exterior surfaces. This building stone has been
used in many buildings in South Florida, particularly in the Miami
area on exteriors as well as interiors.
































Figure 24
Quarry of the Bradenton Stone Company, Manatee County.




MINING AND MINERAL RESOURCES


Figure 25
Cutting "Travertine" at the Bradenton Stone Company, Manatee County.


Figure 26
Splitting "Travertine" at the Bradenton Stone Company, Manatee County.





84 FLORIDA GEOLOGICAL SURVEY-BULLETIN THIRTY-NINE


Dimensional


Figure 27
stone quarry in the Key Largo limestone, Windleys
County.


Key, Monroe


Figure 28
Detailed view of Key Largo limestone at Keystone Art Company's quarry on
Windleys Key, Monroe County.




MINING AND MINERAL RESOURCES


The Marianna limestone of Oligocene age which is found in
Jackson County, was formerly quarried by several companies. In
recent years, however, the only production has been by individuals
on special order and an organized company no longer exists in
that area to produce dimensional stone. The Marianna limestone
was used chiefly to produce building stones. These were the ap-
proximate size of concrete blocks and were used in load-bearing
walls. As noted above, the changes that have come to pass in the
construction industry have all but eliminated dimensional stone for
that purpose.
In general, the dimensional stone industries do not enjoy pros-
pects for future expansion. Newer construction materials, archi-
tectural concrete, glass, aluminum, and others, compete with stone,
nevertheless, these substitute materials cannot replace the dignity
that is associated with stone.
CRUSHED OR BROKEN STONE
Limestone, in its broader sense, includes dolomite and together
these carbonate rocks are the most widely used of all rock. Almost
the entire production of rock or stone in Florida is some variety of
limestone. In 1955, the data collected by the U. S. Bureau of Mines
and the Florida Geological Survey shows that commercial lime-
stone was produced from 73 quarries located in 18 counties, see ac-
companying list, table 12, page 102. With reference to the resource
map (in pocket), it may be seen that there is a concentration of
quarries in Dade and Broward counties and in the northwestern
portion of peninsular Florida, including Suwannee, Lafayette,
Dixie, Alachua, Levy, Marion, Citrus, Sumter, and Hernando coun-
ties. Dolomite is produced from locations in Levy, Citrus, and
Manatee counties. The quantity and value of crushed limestone
produced in recent years is recorded in table 9. It is interesting
to note that the value assigned to the crushed limestone produced
in 1956 is nearly equal to the value of the entire mineral industry
of Florida for the year 1945.
The greatest tonnage of crushed limestone is consumed in uses
classified as concrete, road metal, and screenings. In 1955, the year
for which the most recent data are available, over 82 percent of the
tonnage was consumed in these uses. The tonnage of agricultural
limestone (including dolomite) amounted to nearly 21/2 percent of
the entire production of crushed limestone. Riprap, railroad bal-
last, portland cement, lime, fuel oil additive and other miscel-
laneous uses accounted for the remainder of the production. The
exact totals for these uses are not available for publication at the





86 FLORIDA GEOLOGICAL SURVEY-BULLETIN THIRTY-NINE


Table 9

Crushed Limestone Sold or Used by Producers
1945 through 1956


Year Short Tons Value

1945-1949 average 3,470,608 $ 4,097,991
1950 5,313,400 6,885,394
1951 8,032,966 9,419,682
1952 7,836,124 9,572,575
1953 9,428,959 11,309,421
1954 14,225,356 16,832,066
1955 16,303,625 21,312,339
1956 17,303,000 24,123,000
Data-U. S. Bureau of Mines
*Includes stone used in cement and lime manufacture.

request of the producing companies and of the policy adapted by
the U. S. Bureau of Mines to avoid disclosure of production data
from individual operations. All of the limestone quarries in the
State are of the "open pit" variety; in fact, there are no mines or
quarries of either the drift or shaft types to be found in Florida.
The dolomite or dolomitic limestone that is quarried at Lebanon,
Levy County, is a dolomitic facies of the Ocala group, upper Eocene
and Avon Park limestone of middle Eocene age. This rock is pro-
duced for agricultural stone. At Red Level, Citrus County, a poorly
consolidated dolomitic facies of the lower limestone formation of
the Ocala group, upper Eocene age, is quarried. This rock is pul-
verized and is used as a fuel oil additive to produce a fluffy boiler
scale that is easily removed from boilers. Dolomites and dolomitic
limestone facies of the formations in the Ocala group occur in
western Taylor and Dixie counties. The dolomite .that is quarried
in Manatee County is early or possible middle Miocene and is a
facies of the Hawthorn formation. This rock is quarried not only
for agricultural limestone, see figure 29, but also for dimensional
stone, see figures 25 and 26.
In general, the limestones of the Ocala group that are quar-
ried in Alachua, Levy, Marion, Citrus, Sumter, and Jackson coun-
ties have a uniform texture that allows ready crushing and pul-
verizing. They are free from grit and the rock approaches the
purity of 100 percent calcium carbonate. Rock used in highway
construction for base course material that is produced from the
Ocala group of formations must meet the State Road Department's
specifications of a purity not less than 95 percent calcium and





MINING AND MINERAL RESOURCES


Figure 29
Dolomite quarry of the Southern Dolomite Company, Palmetto, Manatee
County.

magnesium carbonate. In spite of their purity, these limestones
enter into many common uses which include road base material
and concrete aggregate. Part of these formations contain cherty
concretions and boulders and these are eliminated during the
quarrying. In former years, chert boulders were collected from
the surface in Alachua, Marion and Sumter counties for crushing
and for shaping into blocks for furnace linings. This industry,
however, ceased a number of years ago and is mentioned only for
historical record.
The Marianna limestone of Oligocene age has been mentioned
in the discussion of dimensional stone. The Suwannee limestone
of Oligocene age is quarried in Suwannee County at the Ralph
quarry of the Suwannee Limerock Company and the Live Oak
quarry of the Live Oak Stone Company, see figure 30. This forma-
tion varies in character from a hard, resonant limestone to a soft,
granular limestone that contains clay and sand. In the Brooks-
ville area of Hernando County, limestones of Oligocene age (Su-
wannee limestone) and Miocene age (Tampa formation) are quar-
ried extensively and are designated commercially as "Brooksville
Stone." In Hernando County, these formations are hard and mas-
sive but they contain impurities of chert and clay. Figure 31, a
































Figure 30
Live Oak Stone Company quarry, Live Oak, Suwannee County. Approximately 35 feet
of Suwannee limestone is exposed in this quarry. The overburden consists of 12 feet
of clay and three feet of weathered limestone.

M





































Figure 31
Lansing quarry, Florida Rock Products Corporation, Hernando County.





90 FLORIDA GEOLOGICAL SURVEY-BULLETIN THIRTY-NINE

picture of the Lansing quarry, Florida Rock Products Company,
Hernando County, shows a 60-foot face of Suwannee limestone.
The "Brooksville Stone" is used for cement manufacture, rail-
road ballast, concrete aggregate, and agricultural stone.
The limestone formations of the Pleistocene epoch that occur
along the east coast of Florida from the vicinity of St. Augustine,
St. Johns County, southward to Key Largo, and then westward to
Key West, Monroe County, contain some of the largest quarry
operations in the State. The Anastasia formation produced the
first building rock that was used by the settlers at St. Augustine.
A conspicuous part of this formation is the coquina, a rock com-
posed of whole or broken shells that are more or less firmly ce-
mented, and the harder portions of the coquina make the attrac-
tive and durable building stone. Other portions of the formation
consist of sand, calcareous sandstone, sandy limestone and shell
marl; south of the Palm Beach-Broward County line, the Ana tasia
formation merges into the Miami oolite. Figure 32, a photograph
of a small quarry on Anastasia Island, shows layers of uncpnsoli-
dated shell and sand alternating with firm or consolidated layers.
The slabs of the harder portions are fashioned into building stone






















Figure 32
Coquina quarry in Anastasia formation, Anastasia Island, St. Johns County.
Coquina quarry in Anastasia formation, Anastasia Island, St. Johns County.









::;~::n:~:1:~;:::~:
.I'
~..., .:
:." -~ :::':: ~: :
:.: :""'


*..."
. . . .. .


Figure 33
The Lehigh Portland Cement Company's Bunnell plant. Coquina is dredged from the
pit adjacent to the plant. Photograph courtesy of the company.


:::;. .:::
.:::::.





92 FLORIDA GEOLOGICAL SURVEY-BULLETIN THIRTY-NINE

while the sand and shell is used for aggregate. One of the largest
quarries on the east coast of Florida is located adjacent to the
Bunnell plant of the Lehigh Portland Cement Company, see figure
33. The quarry or pit adjacent to the mill produces shell and sand
from the Anastasia formation. This mixture is screened and a
portion of the sand is recombined with the shell for cement manu-
facture. This plant began operation in December 1952, and this is
the first extensive use of coquina.
From a commercial quarrying point of view, the Miami oolite is
the most important limestone in Broward, Dade, and Monroe coun-
ties. It underlies the Atlantic coastal ridge that extends along
the eastern portion of Broward and Dade counties and in Monroe
County it is below sea level in Florida Bay but it forms the\lower
Florida Keys from Big Pine Key to Key West. Generally, thi4 for-
mation is a comparatively soft, white limestone composed of small
spherical grains, or oolites, sand and shell fragments. The lime-
stone often contains solution holes and channels and in some'places
these have been filled with crystals of secondary calcite. In 1953,
the last year for which production data have been released for
the limestone produced in each of the counties, the combined pro-
duction from Broward and Dade counties totaled 5,932,000 short



** ^ '" ""
:. ?.

















Figure 34
Smith Brothers' quarry, Brevard County. Draglines pile Miami oolite in
windows to drain before loading onto trucks.





MINING AND MINERAL RESOURCES


tons valued at $5,830,000. This tonnage represents 63 percent of
the limestone quarried in the entire State and 51- percent of the
value assigned to the limestone production for 1953. The quarries
are large rectangular pits that may cover an area as much as one-
fourth mile wide and one-half mile long. These pits are dug to a
depth of 20 to 40 feet, depending upon the thickness of the forma-
tion. The quarrying operation is illustrated in figure 34, a picture
of Smith Brother's quarry, Brevard County. The leading limestone-
producing companies have been progressive in planning land-use
programs for the quarry sites rather than abandoning them. With
the cooperation of planning and zoning groups, the companies are
engaged in developing the quarries in such a manner as to create
attractive and safe sites for residential use. Almost all of the
production of stone from quarries in Dade, Broward, and Monroe
counties finds use in either the building industry or in road con-
struction.

SAND AND GRAVEL

Commercial sand production comprised 91 percent of the sand
and gravel industry in 1954; while this percentage was about the
same for both 1955 and 1956, the quantity and value of gravel
production for these years have not been disclosed by the U. S.
Bureau of Mines. Listed in order of tonnage, sand and gravel
produced in Florida enters into the following uses: structural
sand, paving sand, structural gravel, paving gravel, railroad bal-
last sand, engine sand, blast sand and molding sand. Although
glass sand is not recorded in these uses, a small tonnage is pro-
duced as a by-product of the kaolin industry in Putnam County.
Table 10 records the growth of sand and gravel industry of Florida
and the 1955 production is at an all time high in both tonnage and
value. By way of contrast, the industry reported the quantity
and value of the 1932 production as 276,068 short tons and
$178,654.
Definitions of sand and gravel vary with use and among au-
thorities but, in general, sand is unconsolidated granular material
that is coarser than 200 mesh and finer than one-fourth inch.
Gravel is coarser than one-fourth inch and finer than 31/2 inches.
Both sand and gravel may be composed of a mixture of many
minerals; nevertheless, a single mineral, usually quartz predomi-
nates. All of the quartz sands of Florida have had a complicated
history and have been transported into the State and are found
in fluvial, deltaic, marine or aeolian deposits. The gravel deposits





94 FLORIDA GEOLOGICAL SURVEY-BULLETIN THIRTY-NINE

Table 10

Quantity and Value of Sand and Gravel Produced in Florida
1945 through 1955

Year Short Tons Value

1945-1949 (average) 1,894,422 $1,717,609
1950 2,793,865 2,806,431
1951 4,418,573 4,300,682
1952 4,154,613 3,848,077
1953 3,731,432 3,199,368
1954 3,468,842 2,661,152
1955 5,065,503 4,349,148
Data-U.S. Bureau of Mnes

that have been worked commercially are fluvial materials. Wi h the
exception of the shell and carbonate content of the coastal hands,
the dominant mineral in the sand deposits is quartz. ven in
the kaolin-bearing sand deposits that are mined and processed for
kaolin, quartz sand that meets specifications for glass manufacture
is produced as a by-product. In fact, most of the commercial sands
fall into the classification of high silica (95 percent or more silica)
sand and the largest producing companies are located in Polk,
Orange, Lake, and Putnam counties on the ridge area of the Penin-
sula. Figure 35 illustrates a typical method of mining sand by
suction dredge. The hydraulic gun is used to undermine the bank
to allow the sand to slump into the pit.
Sand and gravel are low value materials and cannot tolerate
high cost transportation over long distances. Markets must be
found within economic shipping distance. It is interesting to note
the type transportation used in sand and gravel shipments in
Florida and in the United States, see table 11. The marked in-
crease in truck transportation is attributed to the relatively short
haul to market and to the improvement of roads and highways.
Truck transportation is cheaper than rail haul for short distances
and freight costs have increased more rapidly than trucking costs.
The production of sand and of limestone are essential to con-
struction industries and all types of construction buildings, houses,
plants, bridges, highways, etc., are essential to progress. The value
of these commodities is directly proportional to the total value of
construction, and as cost of their production increases so must
the cost of construction.





MINING AND MINERAL RESOURCES


................................
............... .........:..,.........
..::::;"'. :
.................................
........................


Dredge of the All-Florida


Figure 35
Sand Company, Unincorporated,
nam County.


Interlachen, Put-


Table 11


Movement of Sand and Gravel to Market by
Method of Haulage


Type of
Transportation

Railway
Truck
Water and
unspecified


U. S. Average
1942 1955

42% 14%
48% 77%
10% 9%


Data-U. S. Bureau of Mines

SEA WATER AND BRINE

In water-softening systems that utilize zeolite in the water
treatment, it is necessary to regenerate the zeolite by treating it
with brine or sea water. During the past few years, including
1956, there have been four major water-softening plants in Flor-
ida that use sea water for this purpose and one plant that uses
brine pumped from a well. The Rayonier Corporation, Fernan-
dina, has the largest zeolite water-softening system in the State


Florida


1955


1942

60%
15%
25%


!.:-

t~
: :





96 FLORIDA GEOLOGICAL SURVEY-BULLETIN THIRTY-NINE

and it is regenerated by pumping salty water from the tidal
Amelia River that is adjacent to the plant. The zeolite water-
softening systems of Hollywood Beach, Jacksonville Beach, and
Sarasota, all utilize sea water while the City of New Smyrna Beach
uses water from a brine well that has a chloride content in excess of
16,000 ppm. There has not been a canvass of this use of salt
water; nevertheless, it is estimated that the above listed plants
utilize the equivalent of 10,000 tons of salt annually. This use of
sea water and of brine is a significant practice in resource utili-
zation. The utilization of other dissolved solids and their extrac-
tion from sea water as a by-product of desalting sea water is a
distinct possibility. Efforts to develop processes for extraction of
potable water from sea water have been known for centuries, and
the ancient Greeks knew that pure water could be obtained by
evaporating sea water. Efforts to develop economically feasible
processes have lowered the cost of producing such water. Where
the need is sufficiently great, such as aboard ocean ships\ cost
considerations may justify treating sea water to obtain fresh water.
Water for industrial and agricultural uses, however, cannot
be supplied from the sea until lower cost methods are developed.

SELECTED BIBLIOGRAPHY

American Institute of Mining and Metallurgical Engineers
1949 Industrial minerals and rocks: Am. Inst. Min. Met. Eng., New
York, 1156 p.
1952 Problems of clay and laterite genesis: Am. Inst. Min. Met. Eng.,
New York, 244 p.
Amero, R. D.
1951 Fuller's earth, a general review: Min. Engineering, May, 1951,
p. 441-446.
Anderson, Dave
1953 Instrument control in phosphate processing: Rock Products, vol.
56, no. 12, p. 94-96.
Aukland, Merrill F.
1956 Clay mineralogy techniques-a review: Ohio Geol. Survey Inf.
Circ. 20, 31 p.
Avery, William M.
1953 Two modern mills supply ground dolomite for Florida farm
lands: Pit and Quarry, vol. 45, no. 11, p. 87-89, 102.
1953 What owners, builders and lenders should know about concrete
masonry: Pit and Quarry, vol. 46, no. 3, p. 220-224.
Barr, James A., Jr.
1955 (and others) Recovering uranium as a by-product in phosphate
processing: Rock Products, vol. 58, no. 10, p. 96, 98, 100, 102.
1956 Uranium production from phosphate rock: Florida Eng. Soc.
Jour., vol. 10, no. 1, p. 39, 41-47.
Bergendahl, M. H.
1956 Stratigraphy of parts of DeSoto and Hardee counties, Florida:
U. S. Geol. Survey Bull. 1030-B, p. 65-98.
Bowles, Oliver (Also see Van Royen, William)
1956 Limestone and dolomite: U. S. Bur. Mines Inf. Circ. 7738, 29 p.





MINING AND MINERAL RESOURCES 97

Bradley, W. F. (Also see Nagy, B.)
1940 The structural scheme of attapulgite: Am. Mineralogist, vol. 25,
p. 405-413.
Brindley, George W.
1955 Structural mineralogy of clays: California Dept. Nat. Res., Div.
Mines, Bull. 169, p. 33-44.
Browning, J. S.
1956 (and others) Recovery of kyanite and sillimanite from Florida
beach sands: U. S. Bur. Mines Rept. Inv. 5274, 12 p.
Buehrer, T. F.
1955 Role of chemical properties of clays in soil science: California
Dept. Nat. Res., Div. Mines, Bull. 169, p. 177-188.
Butler, Arthur P., Jr.
1952 The Geological Survey's work on the geology of uranium and
thorium deposits: U. S. Atomic Energy Commission, TEI 207,
26 p.
Carpenter, J. H.
1953 (and others) Mining and concentration of ilmenite and associated
minerals at Trail Ridge, Florida: Min. Engineering, vol. 5, no.
8, p. 789-795.
Casperson, W. C.
1948 Heavy gravity minerals in the sands of Florida: Rocks and
Minerals, vol. 23, no. 5, p. 396-397.
Cannon, Harry B.
1950 Economic minerals in the beach sands of the southeastern United
States: in Snyder, F. G., ed., Symposium on mineral resources of
the southeastern United States: Univ. Tennessee Press. 1950, p.
202-210.
Cathcart, J. B.
1950 (and Houser, F. N.) Development and distribution of leached
rock in the land pebble phosphate district, Florida: Geol. Soc.
America Bull., vol. 61, no. 12, pt. 2, p. 1449-1450.
1950 Notes on the land-pebble phosphate deposits of Florida: in Sny-
der, F.G., ed., Symposium on mineral resources of the southeast-
ern United States: Univ. Tennessee Press, p. 132-151.
1953 The geology of the Florida land-pebble phosphate deposits: U. S.
Geol. Survey Preliminary reports (mimeo).
1954 Drilling of airborne radioactivity anomalies in Florida, Georgia,
and South Carolina: U. S. Geol. Survey Preliminary report, 11
p. (mimeo).
S1956 Economic geology of the phosphate deposits of Florida: Econ.
Geology, vol. 51, no. 1, p. 111.
Chew, Frank
1955 On the offshore circulation and a convergence mechanism in the
red tide region off the west coast of Florida: Am. Geophys. Union
Trans., vol. 36, no. 6, p. 963-974.
Conley, John E.
1948 (and others) Production of lightweight concrete aggregates from
clays, shales, slates, and other materials: U. S. Bur. Mines Rept.
Inv. 4401.
Crawford, John E.
1956 (and Paone, James) Facts concerning uranium exploration and
production: U. S. Bur. Mines Handbook, 130 p.
Creitz, E. E.
1948 (and McVay, T. N.) A study of opaque minerals in Trail Ridge,
Florida, dune sands: Am. Inst. Min. Met. Eng. 2426, 7 p.
Dengler, H. F.
1953 Phosphate: Eng. and Min. Jour., vol. 154, no. 2, p. 100-102.
1955 Phosphate: Eng. and Min. Jour., vol. 156, no. 2, p. 108-109.
1956 Phosphate: Eng. and Min. Jour., vol. 157, no. 2, p. 119-122.
Eitel, Wilhelm
1954 The physical chemistry of the silicates: Univ. of Chicago Press,
1592 p.





98 FLORIDA GEOLOGICAL SURVEY-BULLETIN THIRTY-NINE

Engineering and Mining Journal
1952 Florida sands boost supply of titanium mineral: Eng. and Min.
Jour., vol. 153, no. 5, p. 82-87.
1954 By-product uranium output increases: Eng. and Min. Jour., vol.
155, no. 10, p. 122.
Feeley, John C.
1949 Prospect drilling for phosphates in Florida: U. S. Bur. Mines
Inf. Circ. 7500.
Gorski, C. H.
1951 (and others) Raw materials for the mineral-wool industry: U.S.
Bur. Mines Rept. Inv. 4821, 8 p.
Greaves-Walker, A. F.
1949 (and others) The development of a structural clay products in-
dustry using Florida clay: Florida Eng. and Ind. Experiment
Sta. Bull. 30, 48 p.
1951 (and others) The development of lightweight aggregate from
Florida clays: Florida Eng. and Ind. Experiment Sta. Bull. 46,
23 p.
1953 (and Welch, A. P.) The development of mineral wool from Flor-
ida minerals: Florida Eng. and Ind. Experiment Sta. Bull. 59,
28 p.
Grim, Ralph E.
1942 Modern concepts of clay materials: Jour. Geology, vol. 50, no. 3,
p. 225-275.
1953 Clay mineralogy: McGraw-Hill Book Co., Inc., 384 p.
1954 Applications of clay mineral investigations: Georgia Mineral
Newsletter, vol. 7, no. 2, p. 50-53.
Hill, W. L.
1954 (and Jacob, K. D.) Phosphate rock as an economic' source of
fluorine: Min. Engineering, vol. 6, no. 10, p. 994-1000.
Houk, Laurence G.
1943 Monazite sand: U. S. Bur. Mines Inf. Circ. 7233, 19 p.
Houser, F. N. (See Cathcart, J. B.)
Hubbard, Judson S.
1948 Ilmenite, rutile and zircon: Mining World, vol. 10, no. 10, p. 41.
Hudson, W. C.
1943 Rutile, zircon, ilmenite, kyanite: U.S. Bur. Mines War Minerals
Rept. 141, 20 p.
1946 Investigation of the Miami-West Palm Beach belt of silica sand in
Florida: U.S. Bur. Mines Rept. Inv. 3865, 4 p.
Hughes, C. V. O.
1956 Modern hydraulic mining in Florida: Min. Engineering, vol. 8,
no. 1, p. 31-38.
Hunter, F. R.
1948 Occurrence of heavy minerals in the phosphate deposits of Flor-
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Jacob, K. D. (Also see Hill, W. L.)
1953 Fertilizer technology and resources in the United States: Aca-
demic Press Inc., New York, vol. 3, 454 p.
Kenworthy, H.
1956 (and Moreland, M. L.) Laboratory results on testing mineral-
wool raw materials: U.S. Bur. Mines Rept. Inv. 5203, 18 p.
Kerr, Paul F.
1937 Attapulgus clay: Am. Mineralogist, vol. 22, p. 534-550.
1955 Formation and occurrence of clay minerals: California Dept. Nat.
Res., Div. Mines, Bull. 169, p. 19-32.
King, Myrle E. (See Mielenz, Richard C.)
Klein, Howard (See Schroeder, Melvin)
Klinefelter, T. A. (See Tyrrell, M. E.)
Ladoo, Raymond
1951 (and Myers, W. M.) Nonmetallic minerals: McGraw-Hill Book
Co., Inc., 2d ed., 605 p.





MINING AND MINERAL RESOURCES


Larsen, Delmar H.
1955 Use of clay in drilling fluids: California Dept. Nat. Res., Div.
Mines, Bull. 169, p. 269-281.
LeBaron, J. M.
1947 A new core barrel for prospecting for phosphate in Florida:
Am. Inst. Min. Met. Eng. 2089, p. 2-6.
Lee, F. W.
1945 (and others) Magnetic survey of the Florida peninsula: U. S.
Bur. Mines Rept. Inv. 3810, 49 p.
Lenhart, Walter B.
1949 Sand separation-spiral concentrators plus electrostatic separa-
tion: Rock Products, vol. 52, no. 2, p. 102, 103, 135, 136.
1951 Spiral concentrators for gravity separation of minerals: Rock
Products, vol. 54, no. 12, p. 92-95, 131.
Leonardy, S. P.
1953 The phosphate mining industry in Florida: Florida Eng. Soc.
Jour., vol. 7, no. 3, p. 9, 11, 13-15, 17, 19, 41.
Lynd, L. E.
1954 (and others) Characteristics of titaniferous concentrates: Min.
Engineering, vol. 6, no. 8, p. 817-824.
McCarter, W. S. W.
1950 (and others) Thermal activation of attapulgus clay: Ind. Eng.
Chemistry, vol. 42, p. 529-533.
McClain, J. H.
1954 (and Nelson, R. W.) Some useful applications of zirconium: U.S.
Bur. Mines Inf. Circ. 7686, 7 p.
McKelvey, V. E.
1953 (and others) Domestic phosphate deposits: U. S. Geol. Survey
Preliminary report (mimeo).
-MacNeil, F. S8
950 Pleistocene shore lines in Florida and Georgia: U. S. Geol. Sur-
vey Prof. Paper 221-F, p. 95-107.
McVay, T. N. (See Creitz, E.E.)
Martens, James H. C.
1935 Beach sands between Charleston, South Carolina, and Miami,
Florida: Geol. Soc. America Bull., vol. 46, p. 1563-1596.
Merriman, Daniel
1955 El Nino brings rain to Peru: Am. Scientist, vol. 43, no. 1, p.
63-76.
Mielenz, Richard C.
1955 (and King, Myrle E.) Physical-chemical properties and engi-
neering performance of clays: California Dept. Nat. Res., Div.
Mines, Bull. 169, p. 196-254.
Miller, Roswell, III
1945 The heavy minerals of Florida beach and dune sands: Am.
Mineralogist, vol. 30, no. 1, 2, p. 65-75.
Mining World
1955 How Humphreys separates titanium minerals at new Highland
plant: Mining World, vol. 17, no. 12, p. 47-49.
Moreland, M. L. (See Kenworthy, H.)
Myers, W. M. (See Ladoo, Raymond)
Nagy, B.
1956 (and Bradley, W. F.) The structure of sepiolite: Am. Mineralo-
gist, vol. 40, p. 876-884.
Nelson, R. W. (See McClain, J. H.)
Nininger, Robert D.
1956 Minerals for atomic energy: Van Nostrand Co. Inc., 2d ed., 399 p.
Olsen, F. R.
1950 The fluorine content of some Miocene horse bones: Science, vol.
112, no. 2917, p. 620-621.
Overholt, J. L.
1950 (and others) The nature of "arizonite": Am. Minerologist, vol.
35, no. 1, 2, p. 117-119.