sedimentary

Bauxite

Aluminum ore (mixture of gibbsite Al(OH)3, boehmite γ-AlO(OH), and diaspore α-AlO(OH))

AI-generated identification · may be incorrect

Hardness: 1-3 on Mohs scale; Color: Reddish-brown, white, tan, yellow; Luster: Dull to earthy; Structure: Pisolitic (pea-sized rounds) or massive; Specific Gravity: 2.0-2.5.

Hardness: 1-3 on Mohs scale
Color: Reddish-brown, white, tan, yellow
Luster: Dull to earthy

Identified July 17, 2026More sedimentary →

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Physical properties

Hardness: 1-3 on Mohs scale; Color: Reddish-brown, white, tan, yellow; Luster: Dull to earthy; Structure: Pisolitic (pea-sized rounds) or massive; Specific Gravity: 2.0-2.5.

Formation & geological history

Formed by the intense chemical weathering of rocks (like granite or basalt) in hot, humid tropical or subtropical climates. It is a residual soil layer where silica has been leached away, leaving concentrated aluminum oxides.

Uses & applications

The primary ore of aluminum used worldwide. Utilized in the metallurgical industry, abrasive manufacturing, chemical production, and as a refractory material in furnace linings.

Geological facts

Named after the village Les Baux in southern France where it was first discovered in 1821. It is technically a rock composed of several aluminum-rich minerals rather than a single mineral species.

Field identification & locations

Identify by its earthy, dull reddish appearance and often 'pisolitic' texture (looking like small spheres cemented together). Commonly found in Australia, Guinea, Brazil, and Jamaica.