Minerals are natural substances found in the Earth’s crust. They are used to make almost everything around us, including:
Pins
Buildings
Roads
Railway lines
Machines
Cars, buses, trains, and aeroplanes
Household objects
Toothpaste
Food and medicines
Metals such as iron and aluminium are obtained from minerals after mining and refining.
Toothpaste also contains minerals. Silica, limestone, aluminium oxide, and phosphate minerals help clean teeth. Fluorite provides fluoride, which helps prevent cavities. Titanium oxide makes toothpaste white, and mica gives some toothpaste a sparkling appearance.
Living things also need minerals. Although minerals form only a small part of our food intake, they are essential for the body to use other nutrients properly.
A mineral is a naturally occurring substance with a definite chemical composition and internal structure.
Minerals can be:
Hard, like diamond
Soft, like talc
Shiny or dull
Heavy or light
Different in colour and shape
More than 2,000 minerals have been identified, but only a few are commonly found in most rocks.
Rocks are made up of minerals.
Some rocks contain only one mineral. Limestone is an example.
Most rocks contain several minerals in different proportions.
The conditions under which minerals form determine their:
Colour
Hardness
Crystal shape
Lustre
Density
Geographers study minerals to understand:
The structure of the Earth
The distribution of mineral resources
Landforms
Economic activities connected with minerals
Geologists study:
How minerals are formed
Their age
Their physical properties
Their chemical composition
An ore is a natural accumulation of a mineral mixed with other materials from which a metal can be extracted profitably.
The amount of mineral in an ore must be high enough to make mining worthwhile.
Whether a deposit becomes a mine depends on:
The concentration of the mineral
The cost of extraction
The ease of mining
The distance from markets
The quality of the ore
Minerals may occur in cracks, faults, joints, and crevices.
Small deposits are called veins.
Large deposits are called lodes.
These deposits form when molten or gaseous minerals move upward through cracks and cool down.
Tin, copper, zinc, and lead are often found in veins and lodes.
In sedimentary rocks, minerals are usually found in horizontal layers or beds.
They form through:
Deposition
Accumulation
Concentration
Heat and pressure
Coal and some iron ores form this way.
Gypsum, potash salt, and sodium salt may form when water evaporates, especially in dry regions.
Some minerals form when surface rocks break down.
Soluble materials are removed by water, leaving behind a mass containing the ore.
Bauxite is formed in this way.
Placer deposits are mineral deposits found in the sand of valley floors and at the bases of hills.
They usually contain minerals that do not dissolve or corrode easily in water.
Examples include:
Gold
Silver
Tin
Platinum
Ocean water contains many minerals, but most are spread out too widely to be extracted profitably.
Common salt, magnesium, and bromine are obtained from ocean water.
The ocean floor contains manganese nodules.
Minerals are mainly classified as:
Metallic minerals
Non-metallic minerals
Energy minerals
Metallic minerals contain metals.
They are divided into:
Ferrous minerals contain iron.
Examples include:
Iron ore
Manganese
Nickel
Cobalt
Non-ferrous minerals do not contain iron as their main metal.
Examples include:
Copper
Lead
Tin
Bauxite
Precious minerals are valuable and rare.
Examples include:
Gold
Silver
Platinum
Non-metallic minerals do not contain metals as their main component.
Examples include:
Mica
Salt
Potash
Sulphur
Granite
Limestone
Marble
Sandstone
Energy minerals provide energy.
Examples include:
Coal
Petroleum
Natural gas
Rat-hole mining is a type of mining in which miners dig narrow tunnels to reach coal.
It is common in parts of Meghalaya.
The tunnels are so narrow that workers may need to crawl through them.
The National Green Tribunal declared this mining method illegal because it is dangerous and harms the environment.
Minerals are non-renewable resources. They take millions of years to form.
People are using minerals much faster than nature can replace them.
Mineral deposits are limited, and high-quality ores may become difficult and expensive to extract.
We can conserve minerals by:
Using them carefully
Recycling metals
Reusing scrap
Developing substitutes
Using improved technology
Extracting low-grade ores efficiently
Ferrous minerals form a large part of the value of metallic mineral production.
They provide raw materials for industries such as:
Iron and steel
Engineering
Machinery
Transport
Iron ore is the basic mineral for industrial development.
India has large quantities of good-quality iron ore.
Magnetite is the finest iron ore.
It contains up to about 70% iron.
It has strong magnetic properties and is valuable in the electrical industry.
Hematite is the most important industrial iron ore.
It has slightly less iron than magnetite, usually about 50% to 60%.
Most of India’s iron ore production comes from Odisha, Chhattisgarh, Karnataka, and Jharkhand.
High-grade hematite is found in:
Badampahar in Odisha
Mayurbhanj
Kendujhar
Gua in Jharkhand
Noamundi in Jharkhand
This belt covers Chhattisgarh and Maharashtra.
The Bailadila hills in Bastar contain very high-grade hematite.
There are fourteen deposits in this range.
Iron ore from Bailadila is exported to Japan and South Korea through Visakhapatnam port.
This belt is located in Karnataka.
The Kudremukh mines are important deposits.
The ore is transported as slurry through a pipeline to a port near Mangaluru.
This belt includes Goa and Ratnagiri district of Maharashtra.
The ore is not of the highest quality, but it is efficiently mined.
It is exported through Marmagao port.
Manganese is mainly used to make:
Steel
Ferro-manganese alloys
Bleaching powder
Insecticides
Paints
About 10 kilograms of manganese is needed to produce one tonne of steel.
Odisha, Karnataka, Maharashtra, Madhya Pradesh, and Andhra Pradesh are important producers.
India does not have enough reserves of non-ferrous minerals.
Important non-ferrous minerals include:
Copper
Bauxite
Lead
Zinc
Gold
They are important for:
Electrical industries
Engineering
Electronics
Metallurgy
Copper is:
Malleable
Ductile
A good conductor of electricity
It is used in:
Electrical cables
Electronics
Chemical industries
Important copper-producing areas include:
Balaghat mines in Madhya Pradesh
Khetri mines in Rajasthan
Singhbhum district of Jharkhand
Bauxite is a clay-like mineral from which alumina and aluminium are obtained.
It forms when aluminium-rich rocks decompose.
Aluminium is useful because it is:
Strong
Lightweight
A good conductor
Malleable
Major bauxite deposits are found in:
Amarkantak plateau
Maikal hills
Bilaspur-Katni plateau
Odisha
Panchpatmali in Koraput district is an important bauxite deposit.
Odisha was the largest bauxite-producing state in 2018–19.
Limestone is found in sedimentary rocks.
It contains calcium carbonate or calcium and magnesium carbonates.
Limestone is used for:
Making cement
Smelting iron ore in blast furnaces
Building materials
It is the basic raw material of the cement industry.
Mica is made of thin plates or sheets.
It can split easily into very thin layers.
Mica may be:
Clear
Black
Green
Red
Yellow
Brown
It is useful in electrical and electronic industries because it has:
High dielectric strength
Good insulating properties
Low power loss
Resistance to high voltage
Major mica-producing areas include:
Koderma-Gaya-Hazaribagh belt of Jharkhand
Ajmer in Rajasthan
Nellore belt of Andhra Pradesh
Mining can harm miners and the environment.
Miners may suffer from lung diseases because they breathe dust and harmful fumes.
Other dangers include:
Mine roof collapse
Flooding
Fires
Explosions
Dangerous working conditions
Mining can also cause:
Water pollution
Soil pollution
Air pollution
Land degradation
River pollution
Destruction of forests
Waste and slurry from mines can damage nearby land and water sources.
Strict safety rules and environmental laws are necessary.
Mineral deposits are limited and non-renewable.
The amount of usable mineral in the Earth’s crust is very small.
Minerals take millions of years to form, so they cannot be quickly replaced.
Conservation methods include:
Recycling metals
Using scrap metal
Finding substitutes
Improving mining technology
Reducing waste
Using minerals in a planned way
Energy is needed for:
Cooking
Lighting
Heating
Transport
Agriculture
Industries
Machines
Energy resources are classified as:
Conventional sources
Non-conventional sources
Conventional sources are commonly used energy sources.
They include:
Firewood
Cow dung cakes
Coal
Petroleum
Natural gas
Hydroelectricity
Thermal electricity
Non-conventional sources are newer and often renewable sources.
They include:
Solar energy
Wind energy
Tidal energy
Geothermal energy
Biogas
Atomic energy
Firewood and cow dung cakes are commonly used in rural areas.
They provide a large part of rural household energy.
However:
Firewood use contributes to deforestation.
Burning cow dung wastes valuable manure.
Dung can be used to improve soil fertility.
Collecting firewood becomes difficult when forests decline.
Coal is India’s most abundant fossil fuel.
It is used for:
Electricity generation
Industries
Household fuel
Iron and steel production
Coal formed from plant material compressed over millions of years.
Peat has:
Low carbon
High moisture
Low heating capacity
Lignite is soft, brown coal with high moisture.
Important lignite reserves are found at Neyveli in Tamil Nadu.
Bituminous coal is the most commonly used commercial coal.
Metallurgical coal is high-grade bituminous coal used in blast furnaces for making iron.
Anthracite is the highest-quality and hardest coal.
Coal occurs mainly in two geological periods:
Gondwana deposits, more than 200 million years old
Tertiary deposits, about 55 million years old
Major Gondwana coalfields are found in the Damodar Valley.
Important coalfields include:
Jharia
Raniganj
Bokaro
Coal is also found in the:
Godavari Valley
Mahanadi Valley
Son Valley
Wardha Valley
Tertiary coal is found in:
Meghalaya
Assam
Arunachal Pradesh
Nagaland
Coal is bulky and loses weight when burned. This is why heavy industries and thermal power stations are often located near coalfields.
Petroleum is also called mineral oil.
It is used for:
Fuel
Heating
Lighting
Lubricants
Transport
Manufacturing industries
Making chemicals
Petroleum refineries provide raw materials for:
Synthetic textiles
Fertilisers
Plastics
Chemicals
Petroleum is usually found in porous rocks trapped between non-porous layers.
Gas is lighter than oil, so it is usually found above petroleum.
Major petroleum-producing areas include:
Mumbai High
Gujarat
Assam
Important fields in Gujarat include Ankleshwar.
Important oil fields in Assam include:
Digboi
Naharkatiya
Moran-Hugrijan
Assam is India’s oldest oil-producing state.
Natural gas is often found with petroleum.
It is released when crude oil reaches the surface.
Natural gas is used as:
Domestic fuel
Industrial fuel
Power-station fuel
Cooking fuel
Transport fuel
Raw material for fertilisers
Raw material for chemical industries
Compressed natural gas is called CNG.
Piped natural gas is called PNG.
Major gas reserves are found in:
Mumbai High
Bassein fields
Cambay basin
Krishna-Godavari basin
The HVJ pipeline was one of India’s first major cross-country gas pipelines.
It connected gas fields with:
Fertiliser plants
Power stations
Industries
It helped expand the natural gas market in India.
Electricity is used in almost every part of modern life.
Electricity consumption per person is often used as an indicator of development.
Electricity is mainly generated in two ways:
Hydroelectric power
Thermal power
Hydroelectricity is generated using fast-flowing water.
Water turns turbines, and the turbines produce electricity.
Hydroelectricity is renewable.
Examples of multipurpose projects include:
Bhakra Nangal
Damodar Valley Corporation
Kopili Hydel Project
Thermal electricity is generated by burning:
Coal
Petroleum
Natural gas
Thermal power uses fossil fuels, which are non-renewable.
Nuclear energy is produced by changing the structure of atoms.
This releases a large amount of heat, which is used to generate electricity.
Uranium and thorium are used as nuclear fuels.
Important sources include:
Uranium in Jharkhand
Uranium in Rajasthan
Thorium in the monazite sands of Kerala
Solar energy comes from sunlight.
Photovoltaic technology changes sunlight directly into electricity.
Solar energy is useful in rural and remote areas.
It can reduce dependence on:
Firewood
Cow dung cakes
Fossil fuels
It also helps protect forests and provides manure for agriculture.
Wind energy uses moving air to generate electricity.
India has strong wind-power potential.
Important wind-power areas include:
Tamil Nadu
Andhra Pradesh
Karnataka
Gujarat
Kerala
Maharashtra
Lakshadweep
Nagarcoil and Jaisalmer are well-known wind-energy areas.
Biogas is made from the decomposition of organic waste.
Materials used include:
Animal dung
Farm waste
Human waste
Plant waste
Biogas is used for cooking and lighting.
Gobar gas plants use cattle dung.
Biogas provides two benefits:
It gives energy.
It produces better-quality manure.
It also reduces the need to burn firewood and cow dung cakes.
Tidal energy uses the movement of ocean tides.
Dams or floodgates are built across inlets.
Water enters during high tide and flows out through turbines when the tide falls.
Suitable areas include:
Gulf of Khambhat
Gulf of Kachchh
Sundarban regions of West Bengal
Geothermal energy comes from heat inside the Earth.
Deep underground rocks heat groundwater.
The hot water may rise as steam.
The steam can turn turbines to generate electricity.
Experimental geothermal projects are located at:
Manikaran in Himachal Pradesh
Puga Valley in Ladakh
Energy is essential for economic development, but fossil fuels are limited and polluting.
We can conserve energy by:
Using public transport
Switching off unused lights and fans
Using energy-saving appliances
Using renewable energy
Avoiding unnecessary fuel use
Improving energy efficiency
The main idea is that saving energy is equal to producing energy.
Minerals and energy resources are essential for modern life and economic development.
Minerals are limited and take millions of years to form. Energy resources such as coal, petroleum, and natural gas are also being consumed quickly.
We must use resources carefully, recycle materials, reduce pollution, and increase the use of renewable energy such as solar, wind, biogas, tidal, and geothermal energy. jess105.pdf