Gypsum, widespread sulfate mineral of excellent commercial relevance, composed of hydrated calcium sulfate (CaSO4·2H2O). In very well-made crystals the mineral typically has been called selenite. The fibrous huge variety features a silky lustre and known as satin spar; it's translucent and opalescent and is also valued for ornaments and jewellery. https://www.propanraya.com/id/produk/eco-gypsum-ee-4050