210 
FLORIDA GEOLOGICAL SURVEY—15TH ANNUAL REPORT 
Fire tests: 
Temperature. 
Linear Shr. 
Per Cent. 
Absorption. 
Per Cent. 
Porosity. 
Per Cent. 
Color. 
950°C. 
1.2 
18.95 
38.00 
Cream. 
1050 
1.3 
19.78 
38.50 
Cream 
1150 
1.3 
17.30 
38.30 
Cream. 
1190 
1.2 
17.42 
38.50 
Cream. 
1230 
1.3 
18.22 
35.75 
Cream. 
1310 
1.3 
15.20 
35.00 
Cream. 
1430 
1.7 
15.58 
34.80 
Cream. 
A brick plant was formerly operated about one-half mile south of 
the station at DeLeon Springs. The Volusia County Commissioners 
have opened a pit to obtain marl in the same deposit, one-quarter mile 
farther southward. The deposit consists of two feet of sand, four feet 
of gray, plastic clay. The clay is underlain by marl. It underlies an ex¬ 
tensive area in the vicinity of DeLeon Springs. This clay may be used 
for a good grade of common structural materials. It has the following 
physical properties: 
Physical Properties of Volusia County Shell and Marl Clay, DeLeon Springs 
(Lab. No. 0 -J 0 ). 
Excellent. 
Plasticity, judged by feel... 
Water of plasticity. 
Pore water . 
Shrinkage water . 
Linear air shrinkage. 
Volume air shrinkage. 
Modulus of rupture, average 
Slaking test. 
20 . 10 % 
1.90% 
18.20% 
8.0 % 
25.7 % 
532.3 pounds per square inch. 
5 minutes. 
Fire tests: 
T emperature. 
Linear Shr. 
Per Cent. 
Absorption. 
Per Cent. 
Porosity. 
Per Cent. 
Color. 
950°C. 
0.5 
14.69 
34.50 
Brick red. 
1050 
0.5 
14.30 
34.00 
Brick red. 
1150 
1.0 
14.29 
32.70 
Brick red. 
1190 
1.0 
14.33 
31.10 
Brick red. 
1230 
1.5 
13.09 
31.80 
Brick red. 
1370 
1.5 
12.16 
32.25 
Brick red. 
The same conditions prevail a half-mile southward on the property 
of George LaFevre, except that the clay has a thickness of five feet and 
an overburden of only a few inches. The quality of the clay is the same. 
Several pits have been opened and a railway spur built to them. The 
clay is now being removed as an overburden in working the marl. 
Another brick plant was formerly operated at Deep Creek, three 
miles north of DeLeon Springs. This deposit consists of an overburden 
