Bauxite is the most common ore of aluminium. Extraction of aluminium metal takes place in three main stages: mining of bauxite ore, refining the ore to recover alumina, and smelting alumina to produce aluminium. Other raw materials are mined as aluminium ore, but their use is minor compared with bauxite.
The only significant bauxite deposits in Victoria are in South Gippsland. More than forty bauxite occurrences are known in the area. These deposits were formed by deep weathering of early Tertiary Older Volcanics near Mirboo North and Boolarra. Most of the bauxite is overlain by clay, sand and gravel. The bauxite from these sites has been used mainly as an additive to increase the alumina content of cement.
The alumina content of the bauxite deposits in South Gippsland is generally greater than 50% with silica and iron impurities of usually less than 10%. There are also minor deposits of bauxite at Gelliondale and on the Mornington Peninsula.
- Industrial minerals and rocks of Victoria - Geological Survey of Victoria Report 102
- Geological History of Victoria
- Victoria's Minerals, Petroleum and Extractives Industries - Statistical Review