Minerals are naturally occurring substances with a defined internal structure. They are found in rocks and sediments in various forms ranging from hard diamonds to soft talc. Minerals are classified as metallic, which include ferrous, non-ferrous and precious metals, or non-metallic. India's important metallic minerals include iron, manganese, copper and bauxite while non-metallic minerals include mica and limestone. Minerals occur in igneous, metamorphic and sedimentary rocks as well as weathered rocks and alluvial deposits. Energy resources include conventional sources like coal, petroleum and electricity obtained from thermal power plants. Non-conventional energy sources encompass nuclear energy, solar energy, wind