Chat (mining)

"Chat pile" redirects here. For the band, see Chat Pile.
This image, taken in 2010, shows a chat pile near Picher, Oklahoma. These piles contain lead-contaminated dust and are part of the reasons the area is designated as the Tar Creek Superfund site.
Another image, taken in 2006, of chat in the Tar Creek Superfund site.

Chat is fragments of siliceous rock, limestone, and dolomite waste rejected in the lead-zinc milling operations that accompanied lead-zinc mining in the first half of the 20th century. Historic lead and zinc mining in the Midwestern United States was centered in two major areas: the tri-state area covering more than 2,500 square miles (6,500 km2) in southwestern Missouri, southeastern Kansas, and northeastern Oklahoma and the Old Lead Belt covering about 110 square miles (280 km2) in southeastern Missouri. The first recorded mining occurred in the Old Lead Belt in about 1742. The production increased significantly in both the tri-state area and the Old Lead Belt during the mid-19th century and lasted up to 1970.