Gypsum is a soft sulfate mineral composed of Calcium sulfate dihydrate (CaSO4:2H20). It is widely used as a fertilized, in mould, in sculptures and as plaster material. Gypsum is a chalk like material and is very light in weight. It is available in crystalline form in nature. When dry POP powder is mixed with water it hardens. This material which can be applied over brick, block or concrete surface to form a smooth surface is called gypsum plaster.