Hydration Of Anhydrite: Gypsum may also form from the hydration of anhydrite (CaSO₄). Anhydrite is actually a calcium sulfate mineral that lacks the h2o molecules existing in gypsum. When exposed to drinking water, anhydrite undergoes a hydration reaction, incorporating drinking water molecules into its composition and reworking into gypsum. Salt https://www.propanraya.com/id/produk/eco-gypsum-ee-4050