A PRELIMINARY REPORT ON CLAYS OE ELORIDA 
197 
Fire tests: 
T emperature. 
Linear Shr. Absorption. 
Porosity. 
Color. 
Per Cent. 
Per Cent. 
950°C. 
0.37 
35.6 
Red. 
1010 
35.8 
Red. 
1040 
35.6 
Red. 
1070 
36.0 
Red. 
1100 
0.47 
34.8 
Red. 
1130 
33.8 
Red. 
1160 
33.8 
Red. 
1190 
33.7 
Red. 
1220 
0.08 
33.6 
Red. 
1250 
33.7 
Red. 
1280 
33.4 
Red. 
1310 
0.24 
33.6 
Red. 
PUTNAM COUNTY 
Putnam County lies in the St. Johns River valley in the north¬ 
eastern part of the State. The western part of the county is underlain 
by the Alum Bluff formation. Pliocene and Pleistocene sands and marls 
underlie the eastern part of the county. Flood-plain clay deposits are 
common along the St. Johns River. Lacustrine deposits are widely 
scattered over the county. The sedimentary kaolin occurs at several 
points in the southwestern part of the county. These are described in 
Chapter IX. 
Several brick plants have formerly been operated in the region 
around Palatka. The clays were all St. Johns River flood-plain clays. 
A clay formerly worked by the Utica Brick and Tile Company at 
Rice Creek Station may be used for common brick, face brick, hollow 
blocks, fireproofing, and drain tile. This deposit adjoins the Atlantic 
Coast Line Railroad and is located about 100 yards south of the station. 
Its physical properties are: 
Physical Properties of Rice Creek Station Clay (Lab. No. 0 - 42 ). 
Plasticity, judged by feel... 
Water of plasticity. 
Pore water. 
Shrinkage water . 
Linear air shrinkage. 
Volume fire shrinkage. 
Modulus of rupture, average 
Slaking test. 
Excellent. 
24.20% 
0.50% 
23.70% 
7.7 % 
30.5 % 
776.3 pounds per square inch. 
6 hours. 
