120 DETAILED REPORT ON ALABAMA 0LAY8. 



This clay possesses an advantage in the density pro- 

 duced by moderate burning but its high shlinkage would 

 have to be counteracted by the addition of more quartz. 



CHINA CLAY. 

 FBOM J. E. HUGHES, GADSDEN, ALA., (NO. 190.) 



In the lump specimens this clay shows little evidence 

 of stratification. It is mostly white in color, and on the 

 average very fine grained 95 per cent of a lot of the sam- 

 ple sent passing through a 150 mesh sieve. There are 

 scattered through it occasional lumps of the halloysite, so 

 that the material would either have to be ground or 

 washed before shipping it to market. The latter course 

 would be more advisable as it at times shows yellow 

 patches of color. When thrown into water the clay 

 slakes moderately fast to flocculent particles. In wash- 

 ing it tends to stick on the sieve somewhat, and this 

 might cause trouble in pottery manufacture unless ground 

 quartz and feldspar were mixed with it in the proper pro- 

 portions. 



In working it up with water 37.50 per cent of water 

 were required, and gave a mass of high plasticity. 



The bricklets made from this had an air shrinking of 

 8 per cent. 



In burning a noticeable property is the great density at- 

 tained at a comparatively low temperature, but this is al- 

 so accompanied by an additional though not great shrink- 

 age. Thus, at about 2130 F. the total shrinkage was 

 about 14 per cent, and the bricklet very dense; The color 

 was white. At 2250 F. the shrinkage was 15 per cent, 

 and the color white with a faint tinge of gray. At 2350 

 F. the shrinkage remained the same, and the color white 

 with a faint cream tinge. Incipient fusion began at 

 2250 F. 



