Hydrothermal Anhydrite in veins is commonly hydrated to gypsum by groundwater in near-surface area exposures. It is frequently connected to the minerals halite and sulfur. Gypsum is the commonest sulfate mineral.[seventeen] Pure gypsum is white, but other substances found as impurities may well give an array of hues to regional https://www.propanraya.com/id/produk/eco-gypsum-ee-4050