TALC

详情

Talc, Hydrous magnesium silicate Mg3Si4O*0(OH)2 is a hydrous magnesium silicate mineral with a chemical composition of Mg3Si4O*0(OH)2. Although the composition of talc usually stays close to this generalized formula, some substitution occurs. Talc, a mineral made up mainly of the elements magnesium, silicon, and oxygen. As a powder, it absorbs moisture well and helps cut down on friction, making it useful for keeping skin dry and helping to prevent rashes.
Ground talc makes talcum powder. The massive variety (soapstone) is used for sinks, table tops, etc. Soapstone found a use in Babylonian days when signature cylinder seals were often carved from it.
The Egyptians also used it as a base for some of their blue faience figurines, which were then fired to fuse the glaze. California Indians also used it as sculpture material.