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 A rock mainly comprising minerals that are hydrous is aluminum oxides. These minerals are gibbsite, boehmite, and diaspore. Bauxite is a weathering product of aluminous rock that results from intense leaching in tropical and subtropical areas, a process called laterization. Bauxite deposits are generally found on plateaus in stable areas where they had sufficient geologic time to form and were protected from erosion. Bauxite is the primary ore of aluminum. The two types of bauxites that are used commercially as aluminum ores are laterite and karst. Lateritic bauxites constitute more than three-fourths of the world's bauxite resources.
Karstic bauxites are formed on a carbonate ground and are concentrated in sinkholes and solution depressions on the surface of carbonate rocks. Bauxite used to produce alumina is called metallurgical grade; approximately 90% of the world's production is for this purpose. Other major uses are in refractories, abrasives, chemicals, and aluminous cements. The compositional requirements are much more rigid for these uses. The alumina content must be higher, and the iron, silica, and titanium contents significantly lower, than for metallurgical-grade bauxite. World resources of bauxite are many tens of billions of tons, so an adequate supply is assured for hundreds of years. Bauxite does not require complex processing because most of the bauxite mined is of an acceptable grade or can be improved by a relatively simple and inexpensive process of removing clay.
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Recently Updated Articles in Geography of India
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| • | Indian Deciduous or Monsoon Forests
Indian deciduous forests cover the largest forest cover in the country, and are found in a range of landscapes from the plains to the hills. Deciduous forests are so called because the trees of these forests seasonally shed all their leaves. The two major types of deciduous forests are the dry and moist deciduous forests.
| | | • | Rangpo River
Rangpo River is a tributary of the Teesta River. It forms the border between Sikkim and West Bengal states at Rangpo town.
| | | • | Bay of Bengal
Bay of Bengal is a triangular shaped bay in the Indian Ocean, and has derived its name from West Bengal, which lies on the north.
| | | • | Garo Hills
Garo are part of the Garo-Khasi range in Meghalaya. People who reside in the Garo Hills are known as the Garos. The range is part of the Meghalaya subtropical forests eco-region.
| | | • | Cardamom Hills
The Cardamom Hills are known for producing tea, coffee, teak, bamboo and cardamom.
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