sedimentary
Bauxite
Aluminium ore consisting largely of the minerals gibbsite Al(OH)3, boehmite γ-AlO(OH) and diaspore α-AlO(OH)
Hardness 1-3 (Mohs), dull to earthy luster, reddish-brown, white, or tan color, often pisolitic structure, specific gravity 2.0-2.5
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Physical properties
Hardness 1-3 (Mohs), dull to earthy luster, reddish-brown, white, or tan color, often pisolitic structure, specific gravity 2.0-2.5
Formation & geological history
Formed by lateritic weathering of aluminium-bearing rocks in tropical or subtropical climates
Uses & applications
Primary ore of aluminium used to produce alumina and then aluminium metal
Geological facts
Bauxite is named after the village of Les Baux in southern France, where it was first discovered in 1821.
Field identification & locations
Identified by its relatively low density, earthy appearance, and common pisolitic (pea-like) structure. Found mainly in tropical and subtropical regions such as Australia, Guinea, and Brazil.
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