166 DETAILED REPORT ON ALABAMA CLAYS. 



(No. P. S.) 

 POTTERY CLAY (BLUISH.) 



PROM McLEAN POTl ERY, ELMORE CO. 



A compact bluish clay which slakes rather quickly in 

 water. It shows little grit to the taste. It required 20 

 per cent, of water to make a workable mass, which to the 

 feel was smooth and plastic. This mud shrunk 6 per cent, 

 in drying and an additional 6 per cent, in burning, giv- 

 ing a total shrinkage of 1 2 per cent. The average tensile 

 strength of the air dried briquettes was 55 pounds per 

 square inch with a maximum of 66 pounds. Incipient 

 fusion occurred at 1950° F., vitrification at 2150° F. and 

 viscosity at 2400° F. 



The clay burns to a dense, smooth, bluish white body, 

 and should make a good stoneware clay. In burning it 

 bad to be heated slowly. 



The analysis of it is as follows : 



Analysts of Potter]/ Clay, McLean's, Edgewood, Elmore Co. (No. P. 8.A 



Silica (total) 82.60 



Alumina 26.98 



"'^ater g.6o 



Ferric oxide . . . -. 72 



Lime. 



.40 



Magnesia 3g 



Allsalies g5 



Moisture 70 



101.01 



Free silica 30.10 



Total fluxes 213 



Sepcifly gravity 2.37 



STONEWARE CLAY 



PROM NEAR OOOSADA, ELMORE CO. 

 This is a moderately fine grained but somewhat gritty 

 clay, which however is quite plastic, requiring 26.25 per 

 cent, of water to develop its plasticity. 



