Map Of gypsum deposits in northern Ohio, black squares show the location of deposits, from "Geography of Ohio", 1923 Gypsum is Employed in a wide variety of programs: Impurities in refinery gypsum waste have, in several cases, prevented them from getting used as normal gypsum in fields including building. Because https://www.propanraya.com/id/produk/eco-gypsum-ee-4050