Kaolin, flint clay

Acid refractory materials include fireclays, flint clays, china clays (kaolins), silica, flint, chalcedony, ganister and titanium dioxide. 

High alumina clays refer ia the ceramic iadustries to nodular clays, budey-flint clay, budey and diaspore, gibbsitic or bauxitic kaolins (clays), abrasive clays, and others. Siace the depletion of diaspore varieties ia Missouri and Pennsylvania, most bauxitic kaolin and clay is produced ia Alabama and Arkansas. 

The total quantity of potters material—such as Cornish stone, flint, kaolin, china clay, pool day, felspar, et cetera—used in the various departments of manufacture in the Staffordshire potteries, during the year 1859, is estimated at not less than two hundred and twenty thousand tons the. manufactured ware sent out of the district during the same period, reaching over one hundred and ten thousand tons, which, taken at an average value of twenty-five pounds per ton. will give the enormous sum of two millions five hundred thousand pounds sterling. 

Tho crude materials used in England in the manufacture of fine earthenware, are Cornish stone and China clay, a kind of kaolin brought from Cornwall, two varieties of plastic clay, both of which burn white, and chalk-flints. That class called ironstone china is made from ft mixture of plastic clay, kaolin, Comish stone in excess, and silica, Hie formula of which is subjoined —... 

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