Minerals and Energy Resources Notes
1. Minerals: Meaning and Importance
A mineral is a naturally occurring substance with a definite internal structure. Minerals are found in rocks and have different properties such as hardness, colour, lustre, crystal form and density.
Minerals are essential for modern life. They are used in:
- Construction, transport and machinery
- Electrical and electronic equipment
- Industries and agriculture
- Everyday products such as toothpaste and household goods
Rocks may contain one mineral or a mixture of several minerals. The conditions under which minerals form determine their physical and chemical properties.
Mineral vs Ore
- Mineral: A naturally occurring substance found in the Earth’s crust.
- Ore: A mineral-bearing accumulation containing enough useful mineral to make extraction economically worthwhile.
2. Occurrence of Minerals
Minerals occur in different geological formations:
Veins and Lodes
In igneous and metamorphic rocks, minerals may fill cracks, faults and joints.
- Small deposits → veins
- Large deposits → lodes
- Examples: copper, tin, zinc and lead
Beds and Layers
Sedimentary rocks often contain minerals arranged in layers because of deposition and accumulation.
- Coal and some iron ores formed through long periods of heat and pressure.
- Gypsum, potash and sodium salts can form through evaporation.
Residual Deposits
Weathering can remove soluble materials and leave behind a concentrated mineral residue.
- Bauxite is an important example.
Placer Deposits
Some minerals accumulate in river sands and at the base of hills. These are called placer deposits.
- Important examples: gold, silver, tin and platinum
Oceanic Sources
Seawater contains minerals, although many are too dispersed for profitable extraction.
- Common salt, magnesium and bromine are obtained from seawater.
- Ocean floors contain manganese nodules.
3. Distribution of Minerals in India
Mineral resources are unevenly distributed because geological structure, geological processes and the time involved in mineral formation differ from region to region.
The peninsular part of India contains large quantities of:
- Coal
- Metallic minerals
- Mica
- Several non-metallic minerals
The western and eastern sedimentary areas, including Gujarat and Assam, contain important petroleum resources.
A mineral deposit becomes economically useful as a mine when factors such as ore concentration, extraction difficulty and distance from markets make mining viable.
4. Ferrous Minerals
Ferrous minerals contain iron and form an important foundation for metallurgical industries.
Iron Ore
Iron ore is one of India’s most important industrial minerals.
Major types
Magnetite
- Highest-quality iron ore
- Contains up to about 70% iron
- Has strong magnetic properties
- Useful in electrical industries
Hematite
- Most important industrial iron ore by quantity
- Generally contains around 50–60% iron
Major Iron Ore Belts
1. Odisha–Jharkhand Belt
- High-grade hematite occurs in Odisha.
- Important mining areas include Badampahar, Gua and Noamundi.
2. Durg–Bastar–Chandrapur Belt
- Extends through Chhattisgarh and Maharashtra.
- The Bailadila hills of Bastar contain exceptionally high-grade hematite.
- Ore is exported through Visakhapatnam.
3. Ballari–Chitradurga–Chikkamagaluru–Tumakuru Belt
- Located in Karnataka.
- Kudremukh is an important deposit.
- Ore has historically been transported as slurry through pipelines.
4. Maharashtra–Goa Belt
- Includes Goa and Ratnagiri.
- Ore is exported through Marmagao.
Manganese
Manganese is especially important in:
- Steel production
- Ferro-manganese alloy
- Bleaching powder
- Insecticides
- Paints
A significant quantity of manganese is required during steel manufacture.
5. Non-Ferrous Minerals
These minerals do not primarily contain iron. Important examples include copper, bauxite, lead, zinc and gold.
Copper
Copper is:
- Malleable
- Ductile
- A good conductor of electricity
Therefore, it is widely used in:
- Electrical cables
- Electronics
- Chemical industries
Major producing areas mentioned in the chapter include:
- Balaghat, Madhya Pradesh
- Khetri, Rajasthan
- Singhbhum, Jharkhand
Bauxite
Bauxite is the main ore from which alumina and aluminium are obtained.
Aluminium is valuable because it combines:
- Strength
- Low weight
- Good conductivity
- High malleability
Important bauxite regions include:
- Amarkantak Plateau
- Maikal Hills
- Bilaspur–Katni plateau region
Odisha was the leading bauxite-producing state in the data given in the chapter, with Panchpatmali in Koraput being an important deposit.
6. Non-Metallic Minerals
Mica
Mica occurs in thin sheets and can be split into extremely fine layers.
Its major advantages are:
- Excellent insulating ability
- High resistance to voltage
- Low power-loss characteristics
Hence, mica is important in electrical and electronic industries.
Important mica-producing areas:
- Koderma–Gaya–Hazaribagh belt
- Ajmer region of Rajasthan
- Nellore belt of Andhra Pradesh
Limestone
Limestone is associated with rocks containing calcium carbonate or calcium-magnesium carbonates.
It is particularly important because it is:
- A major raw material for cement
- Used in the smelting of iron ore in blast furnaces
7. Hazards of Mining
Mining provides essential resources but can create serious risks.
Effects on miners
- Dust and harmful fumes can cause respiratory problems.
- Mine roofs may collapse.
- Coal mines face dangers from flooding and fires.
Environmental effects
- Water sources may become polluted.
- Mining waste and slurry can damage land and soil.
- Streams and rivers can become polluted.
Therefore, effective safety standards and environmental regulations are necessary.
8. Conservation of Minerals
Minerals are finite and non-renewable resources. They take extremely long periods to form, while humans consume them comparatively quickly.
Continuous extraction can:
- Increase mining costs
- Require deeper mining
- Reduce the quality of available ores
Conservation measures
- Use minerals carefully and efficiently.
- Develop technology for using lower-grade ores.
- Recycle metals and scrap.
- Find suitable substitutes.
- Plan extraction sustainably.
The key idea is that mineral resources must be preserved for future generations.
9. Energy Resources
Energy is necessary for almost every economic activity, including:
- Cooking
- Transport
- Lighting and heating
- Agriculture
- Industries and machinery
Energy sources are broadly divided into conventional and non-conventional sources.
Conventional
- Firewood
- Cattle dung cakes
- Coal
- Petroleum
- Natural gas
- Hydroelectricity
- Thermal electricity
Non-Conventional
- Solar energy
- Wind energy
- Tidal energy
- Geothermal energy
- Biogas
- Atomic energy
10. Coal
Coal is India’s most abundant fossil fuel and is important for:
- Electricity generation
- Industry
- Domestic energy requirements
Coal forms when plant material is compressed over millions of years.
Types of Coal
| Type | Main characteristic |
|---|---|
| Peat | Low carbon, high moisture, low heating value |
| Lignite | Soft brown coal with high moisture |
| Bituminous | Most widely used commercial coal |
| Metallurgical coal | High-grade coal used in iron smelting |
| Anthracite | Hardest and highest-quality coal |
Important Coal Areas
Major Gondwana coalfields include:
- Jharia
- Raniganj
- Bokaro
- Damodar Valley
- Godavari Valley
- Mahanadi Valley
- Son Valley
- Wardha Valley
Tertiary coal occurs particularly in parts of Meghalaya, Assam, Arunachal Pradesh and Nagaland.
Why are industries located near coalfields?
Coal is bulky and loses weight after burning because much of it becomes ash. Locating heavy industries and thermal power stations near coalfields reduces transportation difficulties.
11. Petroleum
Petroleum is India’s major energy source after coal.
Uses
- Fuel and lighting
- Lubricants
- Industrial raw material
- Petrochemicals
- Fertilisers
- Synthetic textiles
Petroleum refineries support many other industries, making petroleum processing an important nodal activity.
Major producing regions
- Mumbai High
- Gujarat
- Assam
Important Assam oil fields include:
- Digboi
- Naharkatiya
- Moran-Hugrijan
Petroleum generally accumulates in porous rocks trapped beneath non-porous layers, often associated with folds and faults.
12. Natural Gas
Natural gas is commonly associated with petroleum deposits.
Uses
- Electricity generation
- Industrial heating
- Fertiliser production
- Petrochemical industries
- Vehicle fuel (CNG)
- Household cooking fuel (PNG)
Important reserves occur around:
- Mumbai High and adjoining western fields
- Cambay Basin
- Krishna-Godavari Basin
Gas pipelines connect production areas with industrial and consuming regions.
13. Electricity
Electricity is widely used in modern life, and per-capita electricity consumption can indicate the level of development.
Hydroelectricity
Generated using flowing water to drive turbines.
Advantages:
- Uses a renewable resource
- Can be associated with multipurpose river projects
Examples mentioned include:
- Bhakra Nangal
- Damodar Valley projects
- Kopili Hydel Project
Thermal Electricity
Generated by burning:
- Coal
- Petroleum
- Natural gas
It therefore depends mainly on non-renewable fossil fuels.
14. Non-Conventional Energy
Growing dependence on fossil fuels creates problems such as:
- Rising fuel costs
- Possible shortages
- Energy-security concerns
- Environmental pollution
Renewable sources can reduce these problems.
Nuclear Energy
Energy is released by changing the structure of atoms and can be used to produce electricity.
The chapter identifies uranium and thorium as important nuclear-energy resources and mentions thorium-rich monazite sands of Kerala.
Solar Energy
Solar technology can convert sunlight directly into electricity.
India has strong potential because of its favourable solar conditions. Solar power can especially benefit rural and remote regions.
Wind Energy
India has substantial wind-power potential.
Important areas include:
- Tamil Nadu
- Andhra Pradesh
- Karnataka
- Gujarat
- Kerala
- Maharashtra
- Lakshadweep
Nagarcoil and Jaisalmer are specifically highlighted for wind-energy use.
Biogas
Biogas is produced when organic waste decomposes.
Sources include:
- Animal waste
- Farm waste
- Shrubs and other organic material
Biogas provides energy while also improving the quality of manure. Cattle-dung plants are commonly called Gobar gas plants.
Tidal Energy
Tides can generate electricity by controlling the movement of seawater through turbines.
Potential areas mentioned:
- Gulf of Khambhat
- Gulf of Kuchchh
- Sunderban region
Geothermal Energy
Geothermal power uses heat from inside the Earth.
Hot groundwater can rise as steam and drive turbines.
The chapter mentions experimental projects at:
- Manikaran, Himachal Pradesh
- Puga Valley, Ladakh
15. Conservation of Energy
Energy demand is continuously increasing across agriculture, industry, transport, commerce and households.
A sustainable energy strategy requires two major approaches:
1. Energy conservation
Use existing energy resources carefully and avoid unnecessary consumption.
2. Greater use of renewable energy
Increase dependence on sources such as solar and wind instead of limited fossil fuels.
What can individuals do?
- Prefer public transport where practical.
- Switch off electrical appliances when not required.
- Use energy-efficient equipment.
- Encourage renewable energy.
Core idea: Saving energy reduces pressure on limited energy resources.
Quick Revision: Must-Remember Points
- Magnetite → finest iron ore; highly magnetic.
- Hematite → most important industrial iron ore by quantity.
- Manganese → important for steel and ferro-manganese.
- Copper → electrical cables, electronics and chemical industries.
- Bauxite → principal ore for aluminium.
- Mica → electrical and electronic industries.
- Limestone → cement industry and iron smelting.
- Coal → India’s major fossil-fuel resource.
- Petroleum → fuel, lubricants and industrial raw material.
- Natural gas → power, industries, CNG and PNG.
- Hydroelectricity → generated using flowing water.
- Thermal electricity → mainly uses fossil fuels.
- Solar/Wind/Tidal/Geothermal/Biogas → renewable or non-conventional sources.
- Minerals are finite and non-renewable → conservation is essential.
- Energy conservation + renewable energy → basis of sustainable energy development.
High-value location facts
Iron ore: Odisha, Jharkhand, Chhattisgarh, Karnataka, Goa/Maharashtra
Copper: Madhya Pradesh, Rajasthan, Jharkhand
Bauxite: Odisha, Chhattisgarh, Gujarat, Maharashtra, Madhya Pradesh, Jharkhand
Mica: Jharkhand, Rajasthan, Andhra Pradesh
Coal: Jharkhand, West Bengal, Odisha, Chhattisgarh, Madhya Pradesh and other coal-bearing regions
Petroleum: Mumbai High, Gujarat, Assam
Natural gas: Mumbai High, Cambay, Krishna-Godavari
Wind: Tamil Nadu and several western/southern states
Geothermal: Manikaran and Puga Valley