CLASS 8 NCERT ALL SUBJECT SHORT NOTES IN ENGLISH

Mineral :- A naturally occurring substance that has a definite chemical composition is a mineral.
Minerals are formed under different conditions in different types of geological environments. They are formed by natural processes, without any human intervention. They can be identified on the basis of physical properties such as colour, density, hardness and chemical properties such as solubility.

Shell :- Mineral is a grouping of one or more minerals with uncertain composition of components.
Although more than 2,800 minerals have been identified.

Types of minerals :- Three thousand on Earth are mainly classified into metallic and non-metallic minerals.

Metallic :- Minerals contain metal in its raw form. Metals are hard substances, which conduct heat and electricity and which have the characteristic of luster.
Example Iron ore, bauxite, manganese ore.

Metallic minerals can be ferrous or non-ferrous.

Iron minerals :- For example, iron ore, manganese, chromite contain iron.

Non-ferrous minerals For example, gold, silver, copper and lead do not contain iron.

Non-metallic :- Minerals do not contain metals. Limestone, mica, and gypsum are examples of these minerals.
Mineral fuels like coal and petroleum are also non-metallic minerals.

Mining of minerals:

1. Mining :- The process of extracting minerals from rocks buried beneath the earth's surface is called mining.

Opencast Mining:- Are removed by removing the dorsal layer.

well mining :- They are made to extract minerals located at greater depth.

2. Penetration :- Petroleum and natural gas are found deep below the surface. To take them out, deep wells are dug, this is called drilling.

3. Drawing :- Minerals located near the surface are easily dug out by the process of digging, which is called mining.

Distribution of minerals :- Minerals are found in different types of rocks. There are three types of rocks

Igneous rock , metamorphic rock , sedimentary rock

metallic minerals Igneous and metamorphic rock groups, which form vast plateaus. Sedimentary rocks are found in the plains and newly folded mountains.

Asia :- China and India have huge iron ore deposits. There are also deposits of manganese, bauxite, nickel, zinc and copper.

Europe :- Europe is the world's leading producer of iron ore. Copper, lead, zinc, manganese, nickel are found.

North America :- The Canadian Shield north of the Great Lakes, the Appalachian region and the mountain ranges to the west contain vast deposits of iron ore, gold, uranium and copper, silver and lead.

South America :- Brazil is the largest producer of high-grade iron ore in the world. There are also huge deposits of gold, silver, zinc, manganese, bauxite, mica, platinum and diamonds.

Africa :- Africa is rich in mineral resources. It is the world's largest producer of diamonds, gold and platinum. Copper, iron ore, chromium, uranium, cobalt, bauxite are found.

Australia :- Australia is the largest producer of bauxite in the world. It is a leading producer of gold, diamonds, iron ore, tin and nickel.

Antarctica :- The geology of Antarctica is fairly well known.

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