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 variety of programs: Gypsum takes place in considerable beds connected to other evaporite minerals (e.g., anhydrite and halite), notably in Permian and Triassic sedimentary formations; https://www.propanraya.com/id/produk/eco-gypsum-ee-4050