sedimentary
Bauxite
Bauxite (mixture of Hydrous Aluminum Oxides)
Hardness: 1-3 Mohs; Color: reddish-brown, tan, or gray; Luster: earthy/dull; Structure: pisolitic (pea-like) or massive; Specific Gravity: 2.0-2.5
- Hardness
- 1-3 Mohs
- Color
- reddish-brown, tan, or gray
- Luster
- earthy/dull
Identified More sedimentary →
Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 1-3 Mohs; Color: reddish-brown, tan, or gray; Luster: earthy/dull; Structure: pisolitic (pea-like) or massive; Specific Gravity: 2.0-2.5
Formation & geological history
Formed through the intense chemical weathering of rocks in hot tropical or subtropical climates, which leaches away silica and results in an accumulation of aluminum oxides. Most deposits date from the Tertiary period through to the present.
Uses & applications
Primary ore of aluminum; also used in the production of abrasives, refractories, chemicals, and cement.
Geological facts
Bauxite is not a single mineral but a rock composed primarily of gibbsite, boehmite, and diaspore. It was first discovered in 1821 near the village of Les Baux in southern France.
Field identification & locations
Identify by its reddish color and 'ooolitic' or 'pisolitic' circular grain textures. Commonly found in Australia, Guinea, Brazil, and Jamaica. Collectors should look for distinct pea-sized structures.
More like this
Other sedimentary specimens
Sandstone or Siltstone
Arenite (if sandstone)
Sedimentary
Sandstone
Arenite (primarily SiO2)
sedimentary
Shale or Slaty Mudstone
Argillaceous sedimentary rock
sedimentary
Chert Breccia
Brecciated Chert (Microcrystalline Silica)
sedimentary
Sandstone (Quartz-rich)
Arenite (SiO2)
sedimentary
Sandstone (with man-made markings)
Arenite (composed primarily of Quartz, SiO2)
sedimentary