Bauxite
Aluminium is earth's most abundant metallic element, making up approximately eight per cent of the planet's crust. Aluminium is commonly found in the form of oxides and never occurs naturally in its pure form.

Bauxite, which is predominantly found in tropical and sub-tropical regions of the world is the most commercially viable source of aluminium. It can be found as rocks or granuals and, depending on its exact composition, it can also vary in colour.

Bauxite is a Sedimentary rock. Sedimentary rocks are derived from decomposed or weathered older rocks which are transported by water, ice or wind to some other place and deposited there. Bauxite is a Chemical Sediment, which means that it is formed from substances dissolved in water which have precipitated, either due to evaporation or to a change in the chemical composition of the solution.

The ore occurs near the surface (usually less than 100 feet), which makes the deposits suitable for mining by simple open cast methods. No drilling or blasting is generally required because of the soft, earthy nature of the ore.

Deposits may be located in areas varying from gentle undulating to rugged, hilly terrain involving major capital expenditures in creating a system to transport the ore.

Even though the ore is generally easy to mine, the process to extract the aluminium from it is genrally complex. The process of making metallic aluminium is carried out in two successive stages:

• the chemical process to extract anhydrous aluminium oxide or alumina
  (A1₂O₃) from the ore.
• the electrolytic process to reduce the alumina to aluminium.