How Is Bauxite Formed?
Bauxite ore is formed when the surrounding soil or rock is dissolved by natural weathering processes until it forms a new type of rock that is usually rich in aluminum ore. Though both types are used for aluminum production, the most valuable type of bauxite ore is lateritic ore.
The type of bauxite ore produced is heavily dependant on the region and conditions the ore is created in. Both types depend on heavy weatherization and above average drainage capacity to form. Latertitic bauxite ores are largely formed in tropical regions by the weathering of silicate rocks like granite, gneiss, basalt, syenite and shale being washed away. These tend to contain the highest concentration of aluminum ores which makes them the most useful for aluminum production.
Karst bauxite ores are largely formed in places like Europe and Jamaica by clay concentration as carbonate rocks like dolomite and limestone weather away to leave the clay and ores behind.
Bauxite is usually strip-mined, because it is typically found near the surface of the local terrain. As of 2010, 70 to 80 percent of the dry bauxite is then used to create aluminum. This is done by a process of heating and cooling the bauxite with various other minerals and gases until alumina is created. Aluminum can be extracted from the alumina by electrolysis.