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Ball Clay's
Ball clay's are highly plastic and contain few mineral impurities. They fire to their mature hardness at about 2336°F (1300°C). When moist they are dark grey and when fired they are either light grey or light buff.
Ball clay's do have a serious drawback. They cannot be used by themselves due to their excessive shrinkage during drying and firing. They are extremely useful, however, when added to other clay's to increase work ability and plasticity.
Ball Clay's
Ball clay's are highly plastic and contain few mineral impurities. They fire to their mature hardness at about 2336°F (1300°C). When moist they are dark grey and when fired they are either light grey or light buff.
Ball clay's do have a serious drawback. They cannot be used by themselves due to their excessive shrinkage during drying and firing. They are extremely useful, however, when added to other clay's to increase work ability and plasticity.