The Cordero Rojo Mine is a coal

Coal

Coal is a combustible black or brownish-black sedimentary rock usually occurring in rock strata in layers or veins called coal beds or coal seams. The harder forms, such as anthracite coal, can be regarded as metamorphic rock because of later exposure to elevated temperature and pressure...

 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...

 complex located in the state

U.S. state

A U.S. state is any one of the 50 federated states of the United States of America that share sovereignty with the federal government. Because of this shared sovereignty, an American is a citizen both of the federal entity and of his or her state of domicile. Four states use the official title of...

 of Wyoming

Wyoming

Wyoming is a state in the mountain region of the Western United States. The western two thirds of the state is covered mostly with the mountain ranges and rangelands in the foothills of the Eastern Rocky Mountains, while the eastern third of the state is high elevation prairie known as the High...

 in the United States, in the coal-rich Powder River Basin

Powder River Basin

The Powder River Basin is a geologic region in southeast Montana and northeast Wyoming, about east to west and north to south, known for its coal deposits. The region supplies about 40 percent of coal in the United States. It is both a topographic drainage and geologic structural basin...

. The mine is of open pit construction and employs several dragline excavator

Dragline excavator

A dragline excavator is a piece of heavy equipment used in civil engineering and surface mining.In civil engineering the smaller types are used for road, port construction, and as pile driving rigs. The larger types are used in strip-mining operations to move overburden above coal, and for...

s. Two coal-processing facilities are located on-site, and crushed coal is shipped by rail to electric utility

Electric utility

An electric utility is a company that engages in the generation, transmission, and distribution of electricity for sale generally in a regulated market. The electrical utility industry is a major provider of energy in most countries. It is indispensable to factories, commercial establishments,...

 customers in the south and west of the United States. The mine employs between 430 and 540 people.

The mining complex is wholly owned by the giant mining company Rio Tinto Group

Rio Tinto Group

The Rio Tinto Group is a diversified, British-Australian, multinational mining and resources group with headquarters in London and Melbourne. The company was founded in 1873, when a multinational consortium of investors purchased a mine complex on the Rio Tinto river, in Huelva, Spain from the...

, thru its subsidiary Rio Tinto Energy America

Rio Tinto Energy America

Rio Tinto Energy America is a wholly owned American subsidiary of the England and Australia-based mining giant, the Rio Tinto Group, headquartered in Gillette, Wyoming...

. It was formed in 1997 from the consolidation of two previously existing mines, the Cordero mine (purchased by Rio Tinto in 1993) and the Caballo Rojo mine (purchased in 1997). The mine produced between 34 and 36 million tons of coal per year in the years 2004 to 2006, and over 40 million tons of coal in 2007, making the Cordero Rojo that year's third-highest producer of coal in the United States.