HOW IS ILLINOIS CLAY USED?
Surface clay, shale, and fireclay are used in the manufacture of structural clay products, such as brick, drain tile, and hollow block ([fig. 16]). Fireclay is used for a bonding agent in molding sand, for the making of stoneware vessels, for a plaster on the walls of industrial furnaces, and for making refractory brick. Refractory brick must be able to withstand very high temperatures and is used to line industrial furnaces, boilers, kilns, and ladles for molten steel.
Shale and clay are ground up and mixed with limestone in the manufacture of cement. Crucibles, refractories, china, and porcelain are made from kaolin. “Fuller’s earth” is used as a sweeping compound and as an animal litter.
Figure 16—Typical Illinois bee-hive kiln.