WOLLASTONITE – CaSiO3 (m.p. 2804o F/1540o C) is a naturally occurring Calcium Silicate, and is mined principally in Willsboro, New York. It can be used to replace Silica and Whiting in clay bodies and glazes. In stoneware bodies (cone 5-13) it will promote low moisture expansion, and improved shrinkage, strength, and thermal shock resistance. When used in a glaze it acts as a Frit of CaCO3 and SiO2 to produce smoother and brighter glazes than Whiting.