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Bauxite wi US penny for comparison

Bauxite, an aluminium ore, is the warld's main soorce o aluminium. It consists maistly o the minerals gibbsite Al(OH)3, boehmite γ-AlO(OH) an diaspore α-AlO(OH), mixed wi the twa airn oxides goethite an haematite, the clay mineral kaolinite an smaa amoonts o anatase TiO2.