Tailor’s chalk

A coarse grayish-green talc rock has been called soapstone or steatite and was formerly much used for stoves, sinks, electrical switchboards, etc, Talc finds use as a cosmetic, for lubricants and as a filler in paper manufacturing. Most tailor s chalk consists of talc. The origin of the word talc is not definitely known. 

Chalk is a soft, relatively porous form of limestone. The term has also been used to describe any light-colored soft material used as a writing medium. The chalk used on blackboards is usually composed mosdy of gypsum, while tailor s chalk, used for marking fabric, is usually made of talc. Chalk has been used as an additive in glass, particularly in thick products that were intended for etching or engraving. 

Tailor s chalk. A thin flat piece of hard chalk or soapstone used by tailors and seamstresses for making temporary marks on cloth... 

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