Gypsum Wikipedia
2020. 8. 27.· Gypsum is a soft sulfate mineral composed of calcium sulfate dihydrate, with the stone formula CaSO 4 ·2H 2 O. It is widely mined and is used as a fertilizer and as the main constituent in many forms of plaster, blackboard/sidewalk chalk, and drywall.A massive fine-grained white or lightly tinted variety of gypsum, called alabaster, has been used for sculpture by many cultures including
