fireclay

English Thesaurus

1. a heat-resistant clay (noun.substance)

hypernym	:	clay,
definition	:	a very fine-grained soil that is plastic when moist but hard when fired (noun.substance)

substance meronym	:	firebrick,
definition	:	brick made of fire clay; used for lining e.g. furnaces and chimneys (noun.artifact)

substance meronym	:	furnace lining, refractory,
definition	:	lining consisting of material with a high melting point; used to line the inside walls of a furnace (noun.artifact)