THE FLORIDA PHOSPHATE DEPOSITS.

LOCAL DETAILS.
;UWANNEE COUNTY.
The southern and southeastern part of Suwannee County has produced some phosphate although only one mine was in operation in this county during 19o9. A variable thickness of pale yellow sand occurs in the pits of this section. At the pits of plant No. IO of Dutton Phosphate Company, 2 miles north of Hildreth from two to twelve feet of this incoherent sand rests directly upon the phosphate bearing matrix. In one of the pits of this plant the phosphate matrix grades at the bottom into a yellow phosphatic clay overlying the limestone to a depth of 4 or 5 feet. In one of the pits at this plant are observed, as frequently seen elsewhere in the hard rock section, many large round elongate siliceous boulder.; interbedded in the phosphate matrix. The underlying formation here is the Ocala Limestone which occurs as peaks, and as "hog backs" of lime projecting into or even through the phosphate matrix.
COLUMBIA COUNTY.
The southern part of Columbia County adjacent to Suwannee County has produced considerable phosphate, although only one mine in this county was in actual operation at the close of I9o9.
At plant No. 2 of the Dutton Phosphate Company about onehalf mile west of Ichatucknee Springs the following section was obtained:
Pale incoherent sand ...................................10 to 20 feet
Phosphate-bearing matrix .............. ................ 20 to 25 feet
Buff yellow phosphatic clays ............................. 5 to 6 feet
Dark sandy phosphatic clays (exposed) .................. t feet
The incoherent sands in this pit, as at Dutton No. io, rest directly upon the phosphate stratum the top of which is exceedingly irregular. Clay lenses 6 to 12 inches thick are of frequent occurrence especially near the top. The underlying Ocala Limestone is reached in places. The buff yellow phosphatic clay observed in Dutton No. io is seen here also and is underlaid by 4 feet of dark sandy phosphatic clay.
The following section was made in one of the pits of the Schilman & Bene Phosphate plant about two miles northwest of Ft. White:
Pale yellow inc, hercnt sand........................... 3 to 5~ feet
Red clayey sands.................... ................. 5 to I0 feet
Phosphate matrix................................... 15 to 25 feet
Limestone at the bottom of the 'it.

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