Aluminum does not occur naturally as a metal. Bauxite ore is refined into alumina and then combined with cryolyte and given a shock, low voltage and extremely high current. The mixture reaches temperatures of close to 900°c. The electricity splits the alumina oxide into molten aluminum and carbon dioxide. The newly formed aluminum drops to the bottom of the crucible and is siphoned off and thus we get aluminum. Although formed at 900°c, aluminum’s melting point is 660°c.
Alumina is abundant in tropical areas like Africa, West Indies, South America and Australia. The smelting is done anywhere that has access to inexpensive power like hydro-electric. Sometimes they build whole power plants just to power an aluminum processing plant. If the power shuts down for more than 4 hours, the molten aluminum solidifies and boom, you have to re-tool the entire plant. With all the fjords and all, Norway’s Norsk Hydro ASA is the worlds 3rd largest producer of aluminum.
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