Hydrothermal Anhydrite in veins is commonly hydrated to gypsum by groundwater in near-floor exposures. It is often linked to the minerals halite and sulfur. Gypsum is the most typical sulfate mineral.[17] Pure gypsum is white, but other substances found as impurities may well give a wide array of colours to https://www.propanraya.com/id/produk/eco-gypsum-ee-4050