Bauxite is a sedimentary rock with a relatively high aluminium content. It is the world's main source of aluminium and gallium. Bauxite consists mostly of the aluminium minerals gibbsite, boehmite and diaspore, mixed with the two iron oxides goethite and haematite, the aluminium clay mineral kaolinite and small amounts of anatase and ilmenite .
Bauxite appears dull in luster and is reddish-brown, white, or tan.
Reddish-brown bauxite
Bauxite with US penny for comparison
Bauxite with core of unweathered rock
One of the world's largest bauxite mines in Weipa, in northern Queensland, Australia
Aluminium is a chemical element; it has symbol Al and atomic number 13. Aluminium has a density lower than that of other common metals, about one-third that of steel. It has a great affinity towards oxygen, forming a protective layer of oxide on the surface when exposed to air. Aluminium visually resembles silver, both in its color and in its great ability to reflect light. It is soft, nonmagnetic, and ductile. It has one stable isotope, 27Al, which is highly abundant, making aluminium the twelfth-most common element in the universe. The radioactivity of 26Al, a more unstable isotope, leads to it being used in radiometric dating.
Aluminium
Bauxite, a major aluminium ore. The red-brown color is due to the presence of iron oxide minerals.
Friedrich Wöhler, the chemist who first thoroughly described metallic elemental aluminium
The statue of Anteros in Piccadilly Circus, London, was made in 1893 and is one of the first statues cast in aluminium.