What is a Mineral ?
Definition : A mineral is a “homogenous, naturally occurring substance with a definable internal structure. Rocks are combinations of homogenous substances called minerals. A particular mineral that will be formed from a certain combination of elements depends upon the physical and chemical conditions under which the material forms. This, in turn, results in a wide range of colours, hardness, crystal forms, lustre and density that a particular mineral possesses. Minerals are found in varied forms ranging from the hardest diamond to the softest talc. Geologists use these properties to classify the minerals.
Mode of Occurrence of Minerals
Definition – The term ‘ore’ is used to describe an accumulation of any mineral mixed with other elements.
- Igneous & Metamorphic Rocks.
(a) Minerals may occur in cracks, crevices, faults or joints. The smaller occurrences are called veins and the larger are called lodes.
(b) In most cases, they are formed when minerals in liquid/molten and gaseous forms are forced upward through cavities towards the earth’s surface.
(c) They cool and solidify as they rise. Major metallic minerals like tin, copper, zinc and lead etc. are obtained from veins and lodes.
- Sedimentary Rocks.
(a) In sedimentary rocks a number of minerals occur in beds or layers. They have been formed as a result of deposition, accumulation and concentration in horizontal strata.
(b) Coal and some forms of iron ore have been concentrated as a result of long periods under great heat and pressure.
(c) Another group of sedimentary minerals include gypsum, potash salt and sodium salt. These are formed as a result of evaporation especially in arid regions.
- In Weathered material.
(a) Another mode of formation involves the decomposition of surface rocks, and the removal of soluble constituents, leaving a residual mass of weathered material containing ores.
(b) Bauxite is formed this way.
- Alluvial Deposits or Placer deposits.
(a) Certain minerals may occur as alluvial deposits in sands of valley floors and the base of hills. These deposits are called ‘placer deposits’ and generally contain minerals, which are not corroded by water. Gold, silver, tin and platinum are most important among such minerals.
- Ocean Water.
(a) The ocean water contains vast quantities of minerals, but most of these are too widely diffused to be of economic significance. However, common salt, magnesium and bromine are largely derived from ocean waters. The ocean beds, too, are rich in manganese nodules.
Distribution of Minerals in India
(i) India is fortunate to have fairly rich and varied mineral resources. However, these are unevenly distributed.
(ii) Broadly speaking, peninsular rocks contain most of the reserves of coal, metallic minerals, mica and many other non-metallic minerals.
(iii) Sedimentary rocks on the western and eastern flanks of the peninsula, in Gujarat and Assam have most of the petroleum deposits.
(iv) Rajasthan with the rock systems of the Peninsula, has reserves of many non-ferrous minerals.
(v) The vast alluvial plains of north India are almost devoid of economic minerals. These variations exist largely because of the differences in the geological structure, processes and time involved in the formation of minerals.
Ferrous and Non-Ferrous Minerals.
| Ferrous Minerals | Non-Ferrous Minerals |
| The minerals having iron content are called ferrous minerals. | The minerals that do not possess iron content are called non-ferrous minerals. |
| Examples : Iron ore, managanese ore, chromium, cobalt, tungsten and nickel. | India is deficient in non-ferrous minerals. |
Ferrous Minerals :
(i) Ferrous minerals account for about three- fourths of the total value of the production of metallic minerals.
(ii) They provide a strong base for the development of metallurgical industries.
(iii) India exports substantial quantities of ferrous minerals after meeting her internal demands.
Iron Ore :
(a) Magnetite is the finest iron ore with a very high content of iron up to 70 per cent. It has excellent magnetic qualities, especially valuable in the electrical industry.
(b) Hematite ore is the most important industrial iron ore in terms of the quantity used, but has a slightly lower iron content than magnetite, (50 – 60 per cent).
The major iron ore belts in India are :
(1) Orissa – Jharkhand belt : In Orissa high grade hematite ore is found in Badampahar mines in the Mayurbhanj and Kendujhar districts. In the adjoining Singbhum district of Jharkhand hematite iron ore is mined in Gua and Noamundi.
(2) Durg – Bastar – Chandrapur belt lies in Chhattisgarh and Maharashtra. Very high grade hematites are found in the famous Bailadila range of hills in the Baster district of Chattisgarh. The range of hills comprise 14 deposits of super high grade hematite iron ore. It has the best physical properties needed for steel making. Iron ore from these mines is exported to Japan and South Korea via Vishahapatnam port.
(3) Bellary – Chitradurga – Chikmaglur – Tumkur belt in Karnataka has large reserves of iron ore. The Kudremukh mines located in the Western Ghats of Karnataka are a 100 per cent export unit. Kudrermukh deposits are known to be one of the largest in the world. The ore is transported as slurry through a pipeline to a port near Mangalore. Slurry is a mixture of water and small pieces of a solid used in an industrial process.
(4) Maharashtra – Goa belt includes the state of Goa and Ratnagiri district of Maharashtra. Though, the ores are not of very high quality, they are efficiently exploited. Iron ore is exported through Marmagao port.
Manganese :
(a) Manganese is mainly used in the manufacturing of steel and ferro- manganese alloy.
(b) Nearly 10 kg of manganese is required to manufacture one tonne of steel. It is also used in manufacturing bleaching powder, insecticides and paints.
(c) Orissa is the largest producer of manganese ores in India. It accounted for one – third of the country’s total production in 2000-01.
Non – Ferrous Minerals
India’s reserve and production of non-ferrous mineral is not very satisfactory. However these minerals, which include copper, bauxite, lead, zinc and gold play a vital role in a number of metallurgical, engineering and electrical industries.
Copper :
(a) India is critically deficient in the reserve and production of copper. Being malleable, ductile and a good conductor, copper is mainly used in electrical cables, electronics and chemical industries.
(b) The Balaghat mines in Madhya Pradesh produce 52 per cent of India’s copper.
(c) The Singbhum district of Jharkhand is also a leading producer of copper. The Khetri mines in Rajasthan are also famous.
Bauxite :
(a) It is from bauxite, a clay- like substance that alumina and later aluminium is are obtained.
(b) Bauxite deposits are formed by the decomposition of a wide variety of rocks rich in aluminium silicates.
(c) Aluminium is an important metal because it combines the strength of metals such as iron, with extreme lightness and also with good conductivity and great malleability.
(d) India’s bauxite deposits are mainly found in the Amarkantak plateau, Maikal hills and the plateau region of Bilaspur – Katni.
(e) Orissa is the largest bauxite producing state in India with 45 per cent of the country’s total production in 2000 – 01. Panchpatmali deposits in Koraput district are the most important bauxite deposits in the state.
Non – Metallic Minerals :
(a) Mica – Mica is a mineral made up of a series of plates or leaves. It splits easily into thin sheets. These sheets can be so thin that a thousand can be layered into a mica sheet of a few centimeters height.
(b) Mica can be clear, black, green, red, yellow or brown.
(c) Due to its excellent di – electric strength, low power loss factor, insulating properties and resistance to high voltage, mica is one of the most indispensable minerals used in electric and electronic industries.
(d) Mica deposits are found in the northern edge of the Chota Nagpur plateau. Koderma Gaya – Hazaribagh belt of Jharkhand is the leading producer.
(e) In Rajasthan, the major mica producing area is around Ajmer. Nellore mica belt of Andhra Pradesh is also an important producer in the country.
Rock Minerals :
(a) Limestone : Limestone is found in association with rocks composed of calcium carbonates or calcium and magnesium carbonates.
(b) It is found in sedimentry rocks of most geological formations. Limestone is the basic raw material for the cement industry and essential for smelting iron ore in the blast furnace.
Conservation of Minerals :
(a) The geological processes of mineral formation are so slow that the rates of replenishment are infinitely small in comparison to the present rates of consumption.
(b) Mineral resources are, therefore, finite and non – renewable.
(c) Rich mineral deposits are our country’s extremely valuable but short – lived possessions. Continued extraction of ores leads to increasing costs as mineral extraction comes from greater depths along with decrease in quality.
(d) A concerted effort has to be made in order to use our mineral resources in a planned and sustainable manner.
(e) Improved technologies need to be constantly evolved to allow the use of low grade ores at low costs.
(f) Recycling of metals, using scrap metals and other substitutes are steps in conserving our mineral resources for the future.
PART-II
Power resources
There are two types of power resources :
(a) Conventional eg. – Coal, petroleum, natural gas, electricity.
(b) Non–conventional eg. – solar, wind, tidal, geothermal, atomic energy and bio gas.
| S.No. | Conventional Sources of Energy | Non–Conventional Sources of Energy |
| 1 | Conventional sources of energy have been in use from time–immemorial. | Non–conventional sources of energy have been identified in the recent past. |
| 2 | They, except water, are exhaustible. | They are inexhaustible. |
| 3 | They cause pollution when used as they emit smoke and ash. | They are inexhaustible. |
| 4 | Power generated from these sources is very expensive to be maintained, stored and transmitted. | They are less expensive. |
| 5 | Example : Coal, mineral oil, natural gas, water, firewood, cattle dung cake. | Geothermal energy, solar energy, wind energy, tidal Energy. |
Coal
(1) Coal is the mainstay of power generation in India. It consititutes about 60% of the total commercial energy consumed in the country. Due to its high utility as source of energy and as raw material for a large number of industries it is often called ‘Black Gold’.
(2) Coal is formed due to the compression of plant material over millions of years. Coal, therefore, is found in a variety of forms depending on the degrees of compression and the depth and time of burial. Decaying plants in swamps produce Peat, which has a low carbon and high moisture contents and low heating capacity. Lignite is a low grade brown coal, which is soft with high moisture content. The principal lignite reserves are in Neyveli in Tamil Nadu and are used for generation of electricity. Coal that has been buried deep and subjected to increased temperatures is Bituminous coal. It is the most popular coal in commercial use. Metallurgical coal is high grade bituminous coal which has a special value for smelting iron in blast furnace. Anthracite is the highest quality hard coal.
(3) The coal bearing strata in India is classified as Gondwana coal field and Tertiary coal fields. The Gondwana coal field
(a little over 200 million age) contributes about 98% of the total production. They are the store houses of India’s metallurgical as well as superior quality of coal.
(4) The major resources of Gondwana coal, which are metallurgical coal, are located in Damodar valley (West Bengal-Jharkhand). Jharia, Raniganj, Bokaro are important coalfields. The Godavari, Mahanadi, Son and Wardha valley also contain coal deposits.
(5) Tertiary coals (about 55 million old) occur in the nort eastern states of Meghalaya, Assam, Arunachal Pradesh and Nagaland.
(6) Coal is bulky mateiral, which loses weight on use as it is reduced to ash. Hence, heavy industries and thermal power stations are located on or near the coalfields.
Petroleum
Most of the oil reserves in India are associated with anticlines and fault traps in sedimentary rock formations of tertiary times. The major oil producing areas of India are divided into (i) North–East India and (ii) West India.
(1) About 63 per cent of India’s petroleum production is from Mumbai High, 18 per cent from Gujarat and 16 per cent from Assam.
(2) Ankeleshwar is the most important field of Gujarat. Assam is the oldest oil producting state of India. Digboi, Naharkatiya and Moran-Hugrijan are the important oil fields in the state.
Natural Gas
Whenever a well of oil is drilled, it is natural gas which is available before oil is struck. Over three–fourth of the total gas comes from Mumbai High. Gas Authority of India limited is the largest company in India for marketing natural friendly gas.
Large reserves of natural gas have been discovered in the Krishna-Godavari basin. Along the west coast the reserves of the Mumbai High and allied field are supplemented by finds in the Gulf of Cambay. Andaman and Nicobar islands are also important areas having large reserves of natural gas.
Hydro Electricity
Hydro electricity is a renewable, cheap, clean and environmental friendly source of energy. India has huge potential of over 84,000 MW but only a small percentage of the coal is developed. This is due to certain geographical factors as well as because of developing stage of economy.
Most of the river flows in India are extremely erratic because they are fed by monsoon wind which are highly seasonal and whimsical. Moreover, many rivers do not have natural waterfall and huge capital has to be invested for constructing dams. Most of the sites suitable for generating hydro electricity are located away from the consuming centre as a result of which a lot of energy is wasted.
Some of the states more dependent on hydroelectricity are :
| State/Area | Percentage of dependence |
| Kerala | 100 |
| Himachal Pradesh | 99.3 |
| Meghalaya | 96.4 |
| Sikkim | 90.0 |
| Karnataka | 79.0 |
| Orissa | 72.0 |
Thermal Energy
It has a special significance in areas where geographical conditions are not favourable for hydroelectricity. In states of Assam, Jharkhand, Gujarat, Mizoram and West Bengal it accounts for over 90% of installed capacity. There are over 310 thermal power plants in India.
Nuclear Energy
Nuclear Energy is obtained from uranium and thorium. Uranium is available in copper belt of Jharkhand and the rocks of Aravali range and Monazite sands of Kerala. Nuclear power contributes 2.9% of total power generation. Most of the nuclear power plants in India have been constructed near sources of water because it is required in great quantity for cooling purpose.
| Location of plant | State |
| Tarapur | Maharashtra |
| Kalpakkam | Tamil Nadu |
| Narora | Uttar Pradesh |
| Kakrapara | Gujarat |
| Rawatbhata | Rajasthan |
| Kaiga | Karnataka |
| Kundankulam | Tamil Nadu |
Solar Energy
        Photo– Voltaic techonology converts sunlight directly into electricity. Being a tropical nation, India has great potential for generation of Solar energy.
        Solar energy is fast becoming popular in rural and remote areas. The largest solar plant of India is located at Madhapur, near Bhuj, where solar energy is used to sterilise milk cans. It is expected that use of solar energy will be able to minimise the dependence of rural households on firewood and dung cakes. Which in turn will contribute to environmental conservation and adequate supply of manure in agriculture.
Wind Energy
              India has vast wind energy potential and wind farms have emerged as viable option with the advancement of wind techonology.
               The largest wind farm cluster is located in Tamil Nadu from Nagarcoil to Madurai. Apart from these, Andhra Pradesh, Karnataka, Gujarat, Kerala, Maharashtra and Lakshadweep have important wind farms. Nagarcoil and Jaisalmer are well known for effective use of wind energy in the country.
Geothermal Energy
        In India, there are about 340 hot spring localities. A 5KW geothermal plant has been commissioned at Manikaran in Kullu district in Himachal Pradesh. A potential of 4–5 MW geothermal power has been estimated in Puga valley of Ladakh in J & K.
Tidal Energy
               India is estimated to possess 8000–9000 MW of tidal energy potential. The Gulf of Khambat is the best suited with 7000 MW potential. This is followed by Gulf of Kuchchh (1000 MW) and Sunderban (1000 MW). A 900 MW tidal power plant is set up in Gulf of Kuchchh by the National Hydropower Corporation.
Biogas
               Shrubs, farm waste, animal and human waste are used to produce biogas for domestic consumption in rural areas. Decomposition of organic matter yields gas, which has higher thermal efficiency in comparision to kerosene, dung cake and charcoal. Biogas plants are set up at municipal, cooperative and individual levels. The plants using cattle dung are known as ‘Gobar Gas plants’ in rural India. These provide twin benefits to the farmer in the form of energy and improved quality of manure. Biogas is by far the most efficient use of cattle dung. It improves the quality of manure and also prevents the loss of tress and manure due to burning of fuel wood and cow dung cakes.
Conservation of Energy Resources
Power energy resources should be conserved by adopting the following measures :
- Conventional resources of power should be used minimally and in their place, non–conventional resources should be used.
- Efficiency of automobile engines should be increased. Electrical motors should be used to the maximum.
- Losses in transmission, transportation and extraction should be stopped or minimized.
- Individuals should use public transport rather than their own vehicles.
- We should switch off electricity when it is not required.
- We should use power saving devices.
New Terms
(1)Â Â Â Â Â Â Â Â Â Â Mineral : Mineral is a natural chemical compound, uniform in composition and structure and constitutes rocks and ores.
(2)Â Â Â Â Â Â Â Â Â Â Mineral ore : Mineral ore is the raw metal extracted from the earth mixed with earth and other impurities. Example : Iron ore.
(3)Â Â Â Â Â Â Â Â Â Â Petroleum : The non-refined mineral oil drilled from the oil wells is called petroleum.
(4)Â Â Â Â Â Â Â Â Â Â Minings : Mining is an economic activity of extracting minerals from the earth. Examples : Mining of petroleum, iron, bauxite etc.
(5)Â Â Â Â Â Â Â Â Â Â Lignite : Low quality brown coal is called lignite.
(6)Â Â Â Â Â Â Â Â Â Â Metallurgical fuel : Non-metallic minerals, used as fuel, are known as metallurgical fuels.
(7)Â Â Â Â Â Â Â Â Â Â Ferro alloys : Ferro alloys are mixed metals with iron as the base.
(8)Â Â Â Â Â Â Â Â Â Â Fossil fuels : The fuels formed because of the decomposition of organisms in the sedimentary rocks are called fossil fuels.
(9)Â Â Â Â Â Â Â Â Â Â Ferrous minerals : Minerals having iron contents are known as ferrous minerals. Example : Iron, manganese.
(10)Â Â Â Â Â Â Â Â Non-ferrous minerals : Minerals which do not have iron content are non-ferrous minerals.Â
               Example : Gold, Silver, Copper, lead.
(11)Â Â Â Â Â Â Â Â Coke : Coke is fully evaporated, solid, hard and blackest form of coal.
(12)Â Â Â Â Â Â Â Â Off-shore drilling : Off-shore drilling is the process of drilling mineral oil from the sea bed, by drilling at the bottom of the sea.
(13)Â Â Â Â Â Â Â Â Metallic minerals : Minerals comprising of metal contents are metallic minerals. Example : Iron-ore, bauxite, copper, gold etc.
(14)Â Â Â Â Â Â Â Â Non-metallic minerals : Minerals which do not have metal contents are non-metallic minerals. Example : Limestone, potash, nitrate.
(15)Â Â Â Â Â Â Â Â Shaft-mines : Deep and tunnelled mines are called shaft mines.
(16)Â Â Â Â Â Â Â Â Veins and Iodes : Smaller occurrences of minerals in cracks, crevices and faults or joints of igneous or metamorphic rocks are called veins and larger occurrences are called lodes. Examples : Metallic minerals like tin, copper, zinc and lead come from veins and lodes.
(17)Â Â Â Â Â Â Â Â Beds or Layers : Beds or layers are the deposits of sediments in layers.
(18)Â Â Â Â Â Â Â Â Placer Deposits : Minerals occurring as alluvial deposits in sands of valley floors and at the base of hills are called placer deposits.
(19)Â Â Â Â Â Â Â Â Rat-hole Mining : Coal mining done in Jowai and Cherapunjee of Meghalaya by community members in the form of long narrow tunnels is known as rat-hole mining.
(20)Â Â Â Â Â Â Â Â Open Pit Mines : The large shallow pit from which mineral ores are obtained is called open pit mine.
(21)Â Â Â Â Â Â Â Â Quarry : Quarry is large surface mine from which stones are excavated. Example : Granite Quarry of Neem ka Thana (Rajasthan)
(22)Â Â Â Â Â Â Â Â Underground Mine with Shafts : Deep and large pits with long tunnels (two to three kilometers in length) are called underground mine with shafts. Example : Dhanbad, Jharia Coal Mines.
(23)Â Â Â Â Â Â Â Â Ore : Ore is the mineral mixed with other elements or impurities. Example : Iron ore.
(24)Â Â Â Â Â Â Â Â Mineral Deposit or Reserve : Known mineral concentration in the ground is called mineral deposit or reserve. Example : Petroleum deposits in Assam and Gujarat.
Add to your knowledge
(1)Â Â Â Â Almost 2000 minerals have been identified in the world so far.
(2)Â Â Â Â Minerals can be classified as metallic and non-metallic, while on the basis of iron content we can classify them as ferrous and non-ferrous minerals.
(3)        Bombay High is the famous off-shore petroleum field of India. It is 115 km west off Mumbai and drills 1 million gallons of petroleum daily.
(4) Â Â Â Â Â Â Â HVJ is a gas pipeline, 1730 km long, carrying 180 lakh cubic metres of natural gas every day, catering to need of 6 fertilizer plants and 3 power plants. It starts from Hazira (Gujarat), passing through Vijaipur (M.P.) and finally reaching Jagdishpur (U.P.). Hence, the name HVJ pipeline.
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