Plaster of Paris is CaSO4.12H2O when it is hydrated CaSO4.2H2O is formed and this product is called gypsum. Gypsum is used as a fertiliser and soil conditioner. It is also used as a finish for wall and ceilings.
POP is used in:
(a) It is used in surgery for setting broken or fractured bones.
(b) It is used for making casts for statues, in dentistry, for surgical instruments and toys etc