Gypsum Mining Encyclopedia of Arkansas
Gypsum is a mineral (CaSO4·2H2O) that occurs in nature as both a mineral and, when in massive form, a rock. Massive deposits are present as sedimentary beds of varying thickness in the subsurface within the Trinity Group in southwest Arkansas. Gypsum beds dip gently to the south, being part of the Early Cretaceous Gulf Coast series of sedimentary deposits. The gypsumbearing De Queen ...