Density and Precise Gravity: Density refers to the mass for each unit quantity of the substance, although certain gravity compares a mineral's density for the density of h2o. Gypsum occurs in intensive beds affiliated with other evaporite minerals (e.g., anhydrite and halite), particularly in Permian and Triassic sedimentary formations; it https://www.propanraya.com/id/produk/eco-gypsum-ee-4050