A white powdery substance used chiefly for casts and molds in the form of a quick-setting paste with water.
The Greeks were among the first to use calcium sulphate to mold clay. Calcium sulphate is a bright white, porous material that is structurally sound. It replaced bisque fired clay molds.
any of several gypsum cements; a white powder (a form of calcium sulphate) that forms a paste when mixed with water and hardens into a solid; used in making molds and sculptures and casts for broken limbs