Gypsum Powder
Gypsum powder (hydrous calcium sulfate/calcium dehydrate or CaSO42H2O) is a white, smooth powder that is derived from heating gypsum gypsum is heated in air it loses water and converts first to calcium sulfate hemihydrate, (bassanite, often simply called quot;plasterquot;) and, if heated further, to anhydrous calcium sulfate (anhydrite). Stucco is applied wet and hardens to a very dense