ASARCO LLC

Limited liability company

A limited liability company is a flexible form of enterprise that blends elements of partnership and corporate structures. It is a legal form of company that provides limited liability to its owners in the vast majority of United States jurisdictions...

is a mining

Mining

Mining is the extraction of valuable minerals or other geological materials from the earth, from an ore body, vein or seam. The term also includes the removal of soil. Materials recovered by mining include base metals, precious metals, iron, uranium, coal, diamonds, limestone, oil shale, rock...

, smelting

Smelting

Smelting is a form of extractive metallurgy; its main use is to produce a metal from its ore. This includes iron extraction from iron ore, and copper extraction and other base metals from their ores...

, and refining

Refining

Refining is the process of purification of a substance or a form. The term is usually used of a natural resource that is almost in a usable form, but which is more useful in its pure form. For instance, most types of natural petroleum will burn straight from the ground, but it will burn poorly...

 company based in Tucson, Arizona

Tucson, Arizona

Tucson is a city in and the county seat of Pima County, Arizona, United States. The city is located 118 miles southeast of Phoenix and 60 miles north of the U.S.-Mexico border. The 2010 United States Census puts the city's population at 520,116 with a metropolitan area population at 1,020,200...

 that mines and processes primarily copper

Copper

Copper is a chemical element with the symbol Cu and atomic number 29. It is a ductile metal with very high thermal and electrical conductivity. Pure copper is soft and malleable; an exposed surface has a reddish-orange tarnish...

. The company, a subsidiary of Grupo México

Grupo México

Grupo México is the largest mining corporation in Mexico and the third largest copper producer in the world.Ferrocarril Mexicano , the company's rail transport division, operates the nation's largest rail fleet.-History:...

, is currently in Chapter 11 bankruptcy. ASARCO planned to emerge from bankruptcy in 2008, and opposes calls for it to totally liquidate its mining and industrial assets.

Its three largest open pit mines are the Mission, Silver Bell and the Ray mines

Copper mining in Arizona

-Jerome:Native Americans used copper minerals of the Verde district at modern-day Jerome as pigment to decorate skin and textiles. The first European to visit the area is thought to be Spanish explorer Antonio de Espejo, who found silver at a location in central Arizona in 1583...

 in Arizona. Its mines produce 350 to 400 million pounds of copper a year.