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minErals

Minerals are the main components of the Rocks. These are the natural inorganic substances
which have a definite chemical composition and physical properties.

• They may be made up of a single element or of a compound of more than one element.
• Minerals are usually crystalline in nature, but a few minerals are non-crystalline.
• Minerals like gold, sulphur and graphite have single element while quartz have more
than one element.

• Copper, iron, gold, etc. are the metallic minerals. They provide us metals.

• Mica and gypsum are the non-metallic minerals. They do not provide us any metal.

To reach the centre of the earth (which is not possible), you will have to dig a hole 6000 km deep
on the ocean floor.

usEfulNEss of miNErals
• Minerals are very important for the development of the mankind.

• They are used in preparing a number of things like computer, sun-glasses, can, pencil,
slates, etc.
• Minerals are used in our day-to-day life. They are used in building houses, bridges,
factories, etc.

• They also provide us precious stones like gems and diamonds.
• Coal, petroleum and natural gas are used as fuels.

• These are also used in the fields of medicines and fertilizers.
• The minerals like iron, aluminium, uranium are used in industries.

roCk CyClE

Rocks undergo a cycle of transformation. Molten magma cools
and solidifies to become igneous rocks. These are broken down,
transported and deposited to form sedimentary rocks. Both igneous
and sedimentary rocks change to metamorphic rocks due to heat
and pressure. Extreme heating will lead to melting of rocks forming
new magma. This magma can again cool and solidify into igneous
rocks. This entire process is called the Rock Cycle.
Rock Cycle

thE importaNcE of rocks aNd miNErals

Types of
Name Use
Rock
Calcite Mineral Used in cements and mortars and the production of lime

Granite Igneous Used for buildings, monuments and tombstones

Social Studies-7-7
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