SPI Geography · Indian Geography — Economy, Resources and Transport
Minerals and Energy
Minerals form in set ways inside rocks and are mined in known belts; the energy we use comes from conventional sources such as coal and oil, and from newer non conventional ones.
Why this matters
Ten questions in the bank, nine EASY and one MODERATE, the biggest page of the chapter: how and where minerals occur, which mine gives which mineral (mica at Koderma, copper at Khetri, thorium in monazite sand), the grades of coal and the oldest oil state.
Concept 1 of 3: What minerals are and how they occur
Everything we use, from a pin to a ship, is made from minerals. A mineral is a natural substance with a fixed make up, and where it is found depends on how it formed.
Definition
- A mineral is a natural substance with a definite internal structure. The physical and chemical conditions under which it forms decide its colour, hardness, lustre and density.
- In igneous and metamorphic rocks, minerals occur in cracks, crevices, faults or joints. Small ones are veins, large ones are lodes (tin, copper, zinc, lead).
- In sedimentary rocks, minerals occur in beds or layers (coal, some iron ore, gypsum, salt).
- When surface rocks are weathered and the soluble parts are washed away, the ore left behind can be valuable: bauxite forms this way.
- Sands of valley floors and the foot of hills hold placer deposits of gold, silver, tin and platinum. Ocean water gives common salt, magnesium and bromine.
- Metallic minerals give metals (iron, copper, bauxite for aluminium); non metallic ones include mica, salt and limestone; energy minerals are coal, petroleum and natural gas.
| Where it forms | Form | Examples |
|---|---|---|
| Igneous and metamorphic rocks | Veins and lodes in cracks, crevices, faults, joints | Tin, copper, zinc, lead |
| Sedimentary rocks | Beds or layers | Coal, gypsum, salt |
| Weathered surface rock | Residue left after soluble parts wash away | Bauxite Bauxite is the ore of aluminium. |
| Sand of valley floors | Placer deposits | Gold, silver, tin, platinum |
| Ocean water | Dissolved | Common salt, magnesium, bromine |
Practice this conceptself-check · 4 quick reps
The same idea in a practice question:
Practice questionEasy
Example 1 · Indian Geography — Economy, Resources and Transport · Minerals and Energy
In igneous and metamorphic rocks minerals may occur in the ____.
Placing gold among weathered residues
Bauxite is the mineral left behind by weathering. Gold and silver are found as placer deposits in sand.
Calling petrol the stuff of everyday things
Petrol is a fuel. The tools, utensils, wires and vehicles we use every day are made of metals obtained from minerals.
Concept 2 of 3: Where the main minerals are mined
Each mineral comes from a few well known belts. Learn the belt with the mineral, because the wrong options are usually real minerals from somewhere else.
Definition
- Mica: the Koderma, Gaya and Hazaribagh belt of Jharkhand is the leading area. Ajmer in Rajasthan and Nellore in Andhra Pradesh also have mica.
- Copper: Khetri mines in Rajasthan, Balaghat in Madhya Pradesh and Singhbhum in Jharkhand.
- Bauxite: the Amarkantak plateau, the Maikal hills and the Bilaspur and Katni plateau; the Panchpatmali deposits are in Koraput, Odisha.
- Thorium: the monazite sands of Kerala are rich in it. Uranium is mined in Jharkhand and the Aravalli ranges of Rajasthan.
| Mineral | Where it is mined |
|---|---|
| Mica | Koderma, Gaya and Hazaribagh belt (Jharkhand); Ajmer; Nellore |
| Copper | Khetri (Rajasthan); Balaghat (Madhya Pradesh); Singhbhum (Jharkhand) |
| Bauxite | Amarkantak plateau; Maikal hills; Panchpatmali in Koraput (Odisha) |
| Thorium | Monazite sands of Kerala Monazite is the thorium sand; uranium comes from Jharkhand and the Aravallis. |
Practice this conceptself-check · 4 quick reps
The same idea in a practice question:
Practice questionEasy
Example 2 · Indian Geography — Economy, Resources and Transport · Minerals and Energy
Koderma, in Jharkhand is the leading producer of which one of the following minerals?
Mixing up thorium and uranium
Both are atomic minerals. Monazite sand of Kerala gives thorium; uranium is mined in Jharkhand and the Aravallis of Rajasthan.
Taking Koderma for an iron or copper mine
Koderma, Gaya and Hazaribagh in Jharkhand are the mica belt. India's copper mines include Khetri in Rajasthan.
Concept 3 of 3: Sources of energy, coal and oil
Energy sources are split into the old, familiar ones and the newer ones. Coal comes in grades by how much carbon it holds, and India's oil was first found in Assam.
Definition
- Conventional sources: firewood, cattle dung cake, coal, petroleum, natural gas and electricity (hydel and thermal).
- Non conventional sources: solar, wind, tidal, geothermal, biogas and atomic energy.
- Coal grades, low to high: peat, lignite (low grade brown coal, soft, with much moisture; main reserves at Neyveli in Tamil Nadu), bituminous (the most used commercial coal) and anthracite (the highest quality hard coal).
- Gondwana coal is in the Damodar valley (Jharia, Raniganj, Bokaro); younger Tertiary coal is in the north east.
- Assam is the oldest oil producing state: Digboi, Naharkatiya and Moran Hugrijan. Ankleshwar in Gujarat and Mumbai High off the Maharashtra coast came later.
| Coal | What it is like |
|---|---|
| Peat | Lowest grade: little carbon, much moisture, gives little heat |
| Lignite | Low grade brown coal, soft, much moisture; main reserves at Neyveli, Tamil Nadu |
| Bituminous | The most popular coal for commercial use |
| Anthracite | The highest quality hard coal |
Oldest oil producing state: Assam (Digboi). Later fields: Ankleshwar (Gujarat), Mumbai High (offshore).
Practice this conceptself-check · 4 quick reps
The same idea in a practice question:
Practice questionEasy
Example 3 · Indian Geography — Economy, Resources and Transport · Minerals and Energy
Which is the oldest oil - producing state of India?
Calling lignite the best coal
Lignite is a low grade brown coal with a lot of moisture. The best, hardest coal is anthracite.
Thinking non renewable means non conventional
Coal, petroleum and natural gas run out, but they are conventional sources because they have long been in common use. Non conventional means the newer ones: solar, wind, tidal, geothermal, biogas, atomic.
Choosing Maharashtra as the oldest oil state
Mumbai High is offshore and came much later. Oil was first struck in Assam, at Digboi.
Summary — formulas & gotchas at a glance
A revision cheat-sheet for the formulas and gotchas above. Click any concept name to jump back to its full explanation.
Reference tables (3)
What minerals are and how they occur5 rows
| Where it forms | Form | Examples |
|---|---|---|
| Igneous and metamorphic rocks | Veins and lodes in cracks, crevices, faults, joints | Tin, copper, zinc, lead |
| Sedimentary rocks | Beds or layers | Coal, gypsum, salt |
| Weathered surface rock | Residue left after soluble parts wash away | Bauxite Bauxite is the ore of aluminium. |
| Sand of valley floors | Placer deposits | Gold, silver, tin, platinum |
| Ocean water | Dissolved | Common salt, magnesium, bromine |
Where the main minerals are mined4 rows
| Mineral | Where it is mined |
|---|---|
| Mica | Koderma, Gaya and Hazaribagh belt (Jharkhand); Ajmer; Nellore |
| Copper | Khetri (Rajasthan); Balaghat (Madhya Pradesh); Singhbhum (Jharkhand) |
| Bauxite | Amarkantak plateau; Maikal hills; Panchpatmali in Koraput (Odisha) |
| Thorium | Monazite sands of Kerala Monazite is the thorium sand; uranium comes from Jharkhand and the Aravallis. |
Sources of energy, coal and oil4 rows
| Coal | What it is like |
|---|---|
| Peat | Lowest grade: little carbon, much moisture, gives little heat |
| Lignite | Low grade brown coal, soft, much moisture; main reserves at Neyveli, Tamil Nadu |
| Bituminous | The most popular coal for commercial use |
| Anthracite | The highest quality hard coal |
Oldest oil producing state: Assam (Digboi). Later fields: Ankleshwar (Gujarat), Mumbai High (offshore).
Watch out for (7)
- Placing gold among weathered residues→ What minerals are and how they occur
- Calling petrol the stuff of everyday things→ What minerals are and how they occur
- Mixing up thorium and uranium→ Where the main minerals are mined
- Taking Koderma for an iron or copper mine→ Where the main minerals are mined
- Calling lignite the best coal→ Sources of energy, coal and oil
- Thinking non renewable means non conventional→ Sources of energy, coal and oil
- Choosing Maharashtra as the oldest oil state→ Sources of energy, coal and oil
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