Mineral Basics
- A mineral = naturally occurring, homogenous substance with a definable internal structure
- Ore = mineral mixed with other elements; metal can be profitably extracted
- Rocks are combinations of minerals
- Extracted by mining, drilling, quarrying
Over 2000 minerals identified, but only a few are abundant in rocks.
Modes of Occurrence
| Mode | Example |
|---|
| Veins & lodes (igneous/metamorphic cracks) | Tin, copper, zinc, lead |
| Beds & layers (sedimentary) | Coal, gypsum, salt |
| Weathering residue | Bauxite |
| Placer (alluvial sands) | Gold, silver, tin, platinum |
| Ocean waters | Common salt, magnesium, bromine |
Ferrous Minerals
- Contain iron; ~3/4 of value of metallic mineral production
- Magnetite — finest ore, ~70% iron, magnetic
- Haematite — most important industrial ore, 50–60% iron
- Manganese — for steel & ferro-manganese (~10 kg per tonne of steel); Odisha largest producer
4 belts: Odisha-Jharkhand, Durg-Bastar-Chandrapur, Ballari-Chitradurga (Kudremukh), Maharashtra-Goa.
Non-Ferrous & Non-Metallic
| Mineral | Use / Area |
|---|
| Copper | Electricals; Khetri (Raj), Balaghat (MP) |
| Bauxite | Ore of aluminium; Odisha largest |
| Mica | Insulator; di-electric; electronics |
| Limestone | Cement; smelting iron ore |
Mining hazards: pulmonary diseases, collapse/flooding, water pollution — a "killer industry".
Conventional Energy — Fuels
- Coal — most abundant fossil fuel; Gondwana (Damodar valley) & Tertiary (NE)
- Grades: Peat < Lignite < Bituminous < Anthracite (carbon rises)
- Petroleum ("black gold") — Mumbai High, Gujarat, Assam (Digboi)
- Natural gas — clean fuel; Krishna-Godavari basin
- Found in anticlines & fault traps
Electricity
- Hydro-electricity — from running water (renewable)
- Thermal — burning coal/petroleum/gas (non-renewable); 310+ plants
- Nuclear/Atomic — uranium & thorium; thorium in Kerala monazite sands
Non-Conventional Energy
| Source | Key Fact |
|---|
| Solar | Photovoltaic; huge potential in tropical India |
| Wind | Largest farm: Nagarcoil–Madurai (TN) |
| Biogas | "Gobar gas" from farm/animal waste |
| Tidal | Gulf of Khambhat, Kutch, Sundarbans |
| Geothermal | Parvati valley (HP), Puga valley (Ladakh) |
Conservation
- Minerals & fossil fuels are non-renewable — form over millions of years
- Use in a planned, sustainable way
- Recycle metals (scrap)
- Use substitutes & improved tech for low-grade ore
- Save energy; shift to renewables
Important Exam Points — Quick Recall
- Magnetite — finest iron ore (~70% iron), magnetic | Haematite — most used industrially
- Bailadila (Chhattisgarh) & Kudremukh (Karnataka) — famous iron-ore mines
- Bauxite — ore of aluminium; Odisha largest producer
- Khetri (Rajasthan) — copper mines
- Digboi (Assam) — oldest oil field | Mumbai High — offshore oil
- Petroleum = "black gold" | Coal grades: Peat → Lignite → Bituminous → Anthracite
- Nagarcoil–Madurai (Tamil Nadu) — largest wind farm
- Thorium — from monazite sands of Kerala (nuclear)
- Gobar gas = biogas from cattle dung & farm waste
- Manganese — ~10 kg to make 1 tonne of steel