Cameco Corporation is the world's largest producer of uranium, generating roughly one-fifth of the total uranium output in the Western world. Cameco's principal source of uranium is the McArthur River mine in northern Saskatchewan, known to be the world's largest high-grade deposit of uranium. Production from this deposit is processed at the Key Lake milling operation. Cameco also has significant uranium operations at Cigar Lake, Saskatchewan, in the United States (Wyoming, Nebraska), and in Central Asia (Kazakhstan). Cameco sells its uranium - and its services to convert uranium into fuel for nuclear power reactors - to companies throughout the Americas, Europe, and Asia. It is also partnered with North America's largest nuclear electricity generating facility, located in southern Ontario, to refine and convert uranium for sale as fuel. Cameco's refining and conversion facilities are located at Blind River and Port Hope, Ontario. Although Cameco's primary focus is the production of uranium and the generation of nuclear electricity, it is also involved in gold mining and exploration, with large operations in Mongolia and the Kyrgyz Republic in Central Asia. Cameco generates annual sales in excess of $700 million and employs a workforce of over 3,200. Since its creation in 1988 through the merger of Eldorado Nuclear Limited and the Saskatchewan Mining Development Corporation (two former Crown corporations), Cameco has maintained its corporate headquarters in Saskatoon.