Hydrothermal Anhydrite in veins is commonly hydrated to gypsum by groundwater in in close proximity to-surface exposures. It is usually affiliated with the minerals halite and sulfur. Gypsum is the most common sulfate mineral.[17] Pure gypsum is white, but other substances uncovered as impurities might give a variety of hues https://www.propanraya.com/id/produk/eco-gypsum-ee-4050