Hydrothermal anhydrite in veins is often hydrated to gypsum by groundwater in in close proximity to-surface area exposures. It is frequently associated with the minerals halite and sulfur. Gypsum is the most typical sulfate mineral.[seventeen] Pure gypsum is white, but other substances found as impurities could give a variety of https://www.propanraya.com/id/produk/eco-gypsum-ee-4050