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