This beautiful Salar de Uyuni is the world's largest salt flat. It is estimated to contain 10 billion tonnes (9.8 billion long tons; 11 billion short tons) of salt, of which less than 25,000 t is extracted annually. Salar de Uyuni attracts tourists from around the world.
The Salar was formed as a result of transformations between several prehistoric lakes. It is covered by a few meters of salt crust, which has an extraordinary flatness with the average elevation variations within one meter over the entire area of the Salar. The crust serves as a source of salt and covers a pool of brine, which is exceptionally rich in lithium. It contains 50% to 70% of the world's known lithium reserves according to a 2009 Foreign Policy article by Joshua Keating.
The Salar contains a large amount of sodium, potassium, lithium and magnesium, as well as borax. With an estimated 9,000,000 t, Bolivia holds about 7% of the world's known lithium resources; most of those are in the Salar de Uyuni.
It is in the Daniel Campos Province in Potosí in southwest Bolivia, near the crest of the Andes at an elevation of 3,656 meters (11,995 ft) above sea level. The Salar serves as the major transport route across the Bolivian Altiplano and is a major breeding ground for several species of flamingos.
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