U. S. Silica Company represents more than a century of mining and processing experience in industrial minerals. The company is a producer of grounded and ungrounded silica sand, kaolin clay, aplite and related industrial minerals. In 1987, Pennsylvania Glass Sand and Ottawa Silica Company merged, forming the present company. The union combined the marketing and production strength of two of North America s top silica companies. Headquartered in Berkeley Springs, W.Va., U. S. Silica Company is located along the East Coast and Midwest in cities such as Mill Creek, Okla.