CHINA CLAYS. 123 



The chemical analysis of the material is as follows: 



Analysis of China Clay near Kymulga, Talladega Co. (No. 205.) 



Silica 50 - 45 



Alumina 35.20 



Ferric oxide 80 



Lime 



Magnesia 62 



Alkalies 



Ignition ~. 12.40 



100.07 

 Total fluxes 2.02 



The clay would no doubt work for the manufacture 

 of white tile; or white earthenware, but could not be 

 used for porcelain without being washed. 



(No. B. S.) 

 CHINA CLAY, 



It is whitish clay, with little or no grit, and of re- 

 markable purity. In water it breaks up slowly to 

 small grains. 



It took 33 per cent, of water to temper it, and gave 

 a lean mass, which shrunk 2 per cent, in drying, and 

 an additional 6 per cent, in burning, giving a total 

 shrinkage of 8 per cent. Air dried briquettes of the 

 clay had an average tensile strength of 25 pounds per 

 square inch, with a maximum of 27 pounds. 



Incipient fusion occurs at 2300 F. vitrification at 

 2500 F., and viscosity above 2700 F. 



The clay burns to a very white, smooth body. 



An analysis of the clay gave the following results : 



