Hydration Of Anhydrite: Gypsum may also kind from the hydration of anhydrite (CaSO₄). Anhydrite is often a calcium sulfate mineral that lacks the water molecules present in gypsum. When exposed to water, anhydrite undergoes a hydration response, incorporating h2o molecules into its construction and transforming into gypsum. Soil Modification: Gypsum, https://www.propanraya.com/id/produk/eco-gypsum-ee-4050