Hydrothermal Anhydrite in veins is often hydrated to gypsum by groundwater in near-surface area exposures. It is commonly connected to the minerals halite and sulfur. Gypsum is the most common sulfate mineral.[seventeen] Pure gypsum is white, but other substances observed as impurities may possibly give a wide array of shades https://www.propanraya.com/id/produk/eco-gypsum-ee-4050