Bauxite
“The aluminum ore that looks like red clay”
Bauxite is a reddish-brown, earthy sedimentary rock and the world's primary source of aluminum. It forms through intense tropical weathering of aluminum-rich rocks, where all soluble minerals are leached away over millions of years, concentrating aluminum hydroxide minerals into economically extractable deposits.
gibbsite, boehmite, diaspore, hematite, goethite, kaolinite
Guinea (world's largest reserves), Australia, Jamaica, Brazil, India, Les Baux-de-Provence (France — type locality)
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Bauxite is named after Les Baux-de-Provence in southern France, where it was discovered in 1821 — today, Guinea alone holds more bauxite than was thought to exist on Earth when it was first identified.
Test Your Knowledge
What specific weathering process concentrates aluminium into economically mineable bauxite deposits?
Photo Attribution
Title: Pisolitic bauxite (Alcoa Bauxite Mine, Arkansas, USA) 8.jpg
Author: James St. John
License: CC BY 2.0
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