Hydrothermal Anhydrite in veins is often hydrated to gypsum by groundwater in close to-area exposures. It is frequently linked to the minerals halite and sulfur. Gypsum is the most common sulfate mineral.[17] Pure gypsum is white, but other substances identified as impurities may possibly give a wide range of colors https://www.propanraya.com/id/produk/eco-gypsum-ee-4050