he history of Mulberry begins with
phosphate. Phosphorus was long recognized
as a vital ingredient in fertilizers, and early sources
of phosphorus included bone black and bird guano.
However, phosphate rock, also called phosphorite,
was found to be a far richer source of phosphorus.
Phosphate rock was first found in South Carolina,
but, in 1880, Dr. C. A. Simmons discovered
phosphate in Alachua County, Florida. The
following year, J. Francis LeBaron, a civilian
engineer with the U. S. Army Corps of Engineers,
found river pebble phosphate while surveying the
Peace River in south central Florida.
A Brief History of Mulberry, Florida
By Richard A. Fifer
Mulberry Historical Society
Florida phosphate mining began on the Peace
River in 1888. At the same time, prospectors
began searching westward for other sources
of phosphate. In the region now called Bone
Valley (because of the many fossils found in
the area), prospectors discovered thick beds
of phosphate rocks, covered only by twenty
to fifty feet of sand and clay. Removing this
“overburden,” and mining the phosphate layer
proved far less expensive than mining river
pebble phosphate or the “hard rock” phosphate
in north Florida.