The Position of the Pebble
Phosphate Industry of Florida in
Stream Sanitation as of
November, 1949
R. B. Fuller, Manager
Florida Phosphate Division
International Minerals and Chemical Corporation
Mulberry, Florida
In order to better understand the problem that the phosphate in¬
dustry in Florida faces in regard to stream sanitation, it is perhaps
well to outline briefly the probable source of the phosphate deposits
as advanced by our geologist.
The ultimate source of phosphorous dates back to the birth of the
earth itself, millions and millions of years ago. Molten rocks cooling
from vast mountain-building pressures and intrusions solidified into
granitoid and gneissic rocks containing small amounts of apatite, a
tricalcium fluophosphate mineral. Exposed to the elements, the rocks
slowly rotted and were washed into streams, and finally most of the
minerals were completely dissolved and the chemical elements, includ-
the phosphorous, took their place in the oceans.
The history of the present phosphate particles begins at least ten
or fifteen million years ago. Billions and trillions of these little pellets
were formed in a sea similar to the present Gulf of Mexico, possibly
as sealife excreta, or as inorganic precipitations from the sea water. As
the pellets formed, calcium carbonate, or limestone, was also precipi¬
tating and some quartz sand was being washed in from the shorelines.
In addition to the phosphates there were thousands of other species
of sea life which withdrew the calcium carbonate from the water to
build their shells and bodies and which contributed largely to the forma¬
tion of the limestone. Many large marine mammals abounded and left
their phosphatic teeth and bones. As the sediments slowly accumulated,
their weight caused compaction and a very gradual sinking of the sea
floor until a thickness of more than 200 feet of rock accumulated. Some
layers were highly phosphatic, some were almost pure limestone, some
were almost all sand, depending on the major source of sediment for
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