Calcination: The Powdered gypsum is heated to remove water molecules, generating distinctive sorts of plaster depending upon the temperature and period of heating. Map of gypsum deposits in northern Ohio, black squares reveal The situation of deposits, from "Geography of Ohio", 1923 Gypsum is Employed in lots of applications: Selenite https://www.propanraya.com/id/produk/eco-gypsum-ee-4050