U.S. Silica's Rockwood plant mines from the Sylvania Sandstone Formation of the Detroit River Group, which partly borders the Rockwood property. The chemical and physical properties of the Rockwood sandstone make it ideal for glass containers and solar glass panels.
The Rockwood property changed hands numerous times in its past, including ownership by the Ford Motor Company, for the purpose of manufacturing foundry sands. Ottawa Silica Company eventually acquired the property in 1944. Since then, there have been continuous expansions and improvements at this location.