Gypsum are available in hydrothermal veins, that happen to be fractures in rocks full of mineral-abundant fluids that originate from deep in the Earth's crust. Map of gypsum deposits in northern Ohio, black squares suggest The situation of deposits, from "Geography of Ohio", 1923 Gypsum is Employed in a wide https://www.propanraya.com/id/produk/eco-gypsum-ee-4050