Theory:

Bauxite
Aluminium is produced from a reddish clay material called bauxite ore. Despite having several other ores that contain aluminium, Bauxite remains the world's primary source of aluminium because of its rich aluminium content.
 
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Bauxite
 
Due to its lightweight and toughness, Aluminium has a wide range of uses compared to other metals. It is also cheaper, which makes it a popular metal for construction purposes. It is mainly used in building aircraft, ships, automobiles, railway coaches etc. Aluminium is a good conductor of heat and electricity. Hence, it is used for making electrical cables. It is also highly resistant to corrosion. By the addition of small quantities of other metals to aluminium, it creates a superior alloy than pure aluminium. E.g: Duralumin.
Australia is the world’s leading bauxite producer. Other important producers of bauxite are China, Brazil, India, Guinea, Jamaica and Russia. Guinea alone has about One-fourth of the bauxite mineral deposits in the world.

Important bauxite producing states in India: Gujarat, Odisha, Jharkhand, Maharashtra, Chhattisgarh, Tamil Nadu and Madhya Pradesh. In Tamilnadu, bauxite deposits are mainly found in the Shevaroy hills of Salem district.
Silver
Like gold, Silver is also a precious metal. But due to its chemical property silver has a wider variety of uses compared to gold. It is used in making jewellery, photographic goods, dentistry, electroplating industry and in the manufacture of luxury goods. About two-third of silver is used for monetary purposes. Similar to gold, silver also resists corrosion.
Mexico is the world’s largest silver producer. Followed by Mexico, Peru, China, Russia, Australia and Chile. More than half of silver is found only in South American countries.
Manganese
Manganese is a hard, brittle steel-greyed silvery metal, often found in minerals in combination with iron. The common ores of manganese are Psilomelane, Pyrolusite Manganese and Rhodochrosite. Manganese is essential for the production of good quality Steel. Manganese is also used in making electrical batteries. It is used as a colouring material in pottery, bricks, floor tiles.
  
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South Africa is the world’s largest producer of manganese. The significant producers of manganese in the world are China, Australia, Gabon, Brazil and India. All these producers have large reserves of manganese and are significant exporters in the world. compounds are used in making fertilizers, disinfecting liquids, bleaching powder, etc.