Hydration Of Anhydrite: Gypsum can also form through the hydration of anhydrite (CaSO₄). Anhydrite is usually a calcium sulfate mineral that lacks the water molecules current in gypsum. When exposed to h2o, anhydrite undergoes a hydration response, incorporating water molecules into its structure and reworking into gypsum. Impurities in refinery https://www.propanraya.com/id/produk/eco-gypsum-ee-4050