Its three largest open-pit mines are the Mission, Silver Bell and Ray mines in Arizona. Its mines produce of copper a year. Asarco conducts solvent extraction and electrowinning at the Ray and Silver Bell mines in Pima County, Arizona, and Pinal County, Arizona, and operates a smelter in Hayden, Arizona. Asarco's smelting plant in El Paso, Texas, was suspended in 1999 and then demolished on April 13, 2013. Before closing, the plant produced of anodes each year. Refining at the mines as well as at a copper refinery in Amarillo, Texas, produce of refined copper each year.