bauxite

Bauxite is the primary ore of aluminum. It consists mainly of hydrated aluminum oxides and hydroxides, with the minerals gibbsite (Al(OH)3), boehmite (AlO(OH), and diaspore (α-AlO(OH)) as the principal constituents. Impurities such as silica, iron oxides, and titania give a range of colors from red-brown to cream. Bauxite forms in tropical environments through prolonged weathering of aluminum-rich rocks, producing lateritic crusts in which nodules or layers accumulate near the surface.

Most bauxite is mined by open-pit methods and refined to produce alumina (Al2O3) for smelting. The Bayer process dissolves aluminum oxide from the ore to yield a concentrated alumina, which is then subjected to the Hall–Héroult electrolytic process to produce aluminum metal. Ore grades vary widely, with typical Al2O3 contents commonly cited from about 30% to 60%, and purity levels and impurities affecting processing costs.

Uses and distribution: Bauxite is the essential raw material for the aluminum industry, underpinning products such as packaging, transportation, construction, and consumer goods. Economically important deposits occur in tropical regions, and leading producers include Australia, Guinea, Brazil, Jamaica, and India, while China is a major consumer and processor of the metal. The name bauxite originates from the village of Les Baux-de-Provence in France, where the ore was first described in the early 19th century by Pierre Berthier.

Environmental and social considerations: Bauxite mining and refining can pose environmental challenges, including habitat disruption, water management, and red mud waste from refining. Responsible mining practices and post-mining rehabilitation are central to modern operations.