Gypsum Plaster : Advantages and Disadvantages Happho
Plaster of Paris is obtained by pulverizing the gypsum (calcium sulphate hemihydrate CaSO 4 2 O) which is heated to a temperature of 150 deg centigrade.. Upon addition of water, Plaster of Paris (POP) becomes regular gypsum (dihydrate) again causing the resultant material to harden.