Bauxite

Bauxite is a sedimentary rock with a relatively high aluminium content. It is the world's main source of aluminium and gallium. Bauxite consists mostly of the aluminium minerals gibbsite, boehmite, and diaspore, mixed with the two iron oxides goethite and hematite, the aluminium clay mineral kaolinite and small amounts of anatase and ilmenite . Bauxite appears dull in luster and is reddish-brown, white, or tan.

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