Bauxite is an oxide of aluminum (name derived after Les Beaux in France). It is a light metal whose colour ranges from white to pink or reddish depending upon the iron content present in it. It is usually pisolitic and has a specific gravity of 2.55. Bauxite is a secondary mineral mainly associated with lateritic rocks formed during Tertiary period.
Sometimes clayey rocks are also changed into bauxite. Bauxite is the product of residual weathering process which leads to the leaching of the silica and is the residual enrichment of aluminum hydrates. In bauxite or the content of alumina generally ranges between 55 and 65 per cent. This ore is associated with two types of minerals: gibbsite (AI2O3, 3H20) and diasporas (A1203, H20).
On account of its great lightness, strength, malleability, ductility, heat and electrical conductivity and resistance to atmospheric corrosion aluminum has become one of the most useful metals of today. Besides its use for utensils, it has many applications in electricity, metallurgy, aeronautics, etc.
It is largely employed in the manufacture of alloys with nickel, copper, zinc and magnesium, which are finding ever widening applications in automobile, aircraft, railway and other engineering construction. It has various industrial uses in the preparation of chemicals, refractoriness, abrasives, and aluminous cement. Where copper is not available or its cost is prohibitive, aluminum is used in long-distance electric transmission cables.
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Occurrence
Bauxite deposits in India are mainly associated with late rites and occur as capping or blankets over high plateaus of the Peninsula except in the Katni area (Jabalpur district) of Madhya Pradesh) and certain coastal tracts of Gujarat and Goa which are low level deposits.
In Maharashtra and adjoining areas these deposits overlie the Deccan Trap formations but elsewhere they rest on various other formations. Laterites rich in bauxite are found in Ranchi, Jabalpur, Balaghat, Kolhapur, Mahabaleswar, Kalahandi, Sambalpur, Belgaum, Saurashtra, Kachchh, Mandla, Palamau and Salem areas. Extensive deposits of bauxite have been discovered in the Nummulitics of Jammu and Punch.
Reserves
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The total recoverable reserves of bauxite in the country are placed at 2,462 million tons while the total in situ reserves are 2,953 million tones. The conditional resources of bauxite are about 752 lakh tannins. In addition, prospective resources are placed at 90 million tons (India 2003, p. 557). According to Indian Minerals Year-book, 1983 the total estimated reserves of bauxite in the country are placed at 2,429 million tones which is about 1 per cent of the world bauxite reserves. More than half (55.29%) of the country’s reserves of bauxite ate found in Orissa.
Andhra Pradesh has about a quartet of the total bauxite reserves of the country. Madhya Pradesh, Maharashtra, Gujarat and Bihar-Jharkhand are other states where sizeable reserves of bauxite have been located (Table 17.XVII). Major reserves are concentrated in the East Coast Bauxite deposit of Orissa and Andhra Pradesh. India has the fifth largest bauxite reserves in the world after Guinea Australia, Brazil and Vietnam.
Prior to Independence the total production of bauxite in the country was less than 40,000 tones. It amounted to 68,000 tons valued at Rs. 7.52 lakhs in 1951. Since then there has been continuous increase in the production of bauxite recording phenomenal growth between 1961-71 (219 per cent) and 1981 -91 (155 per cent). After 1990-91 the growth-rate has been slowed down.
The current production of 97.77 lakh tones (in 2002-03) is 144 times of 1951 which clearly exhibits the accelerated growth of bauxite production in the country due to increasing demand in indigenous aluminum industry. Table 17.XVIII shows the trends in the quantity and value of bauxite production between 1951 and 2002-03.
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Regional Distribution
Orissa with largest reserves of bauxite is the leading producer and has surpassed Jharkhand which now occupies third place in terms of bauxite production in the country. These two states together contribute over 62 per cent of the national output of bauxite. Gujarat, Maharashtra and Madhya Pradesh- Chhattisgarh are other major producers of bauxite.
Huge reserves of bauxite in Andhra Pradesh if worked out will enable it to occupy a significant place amongst the bauxite producing states of the country. Table 17.XIX presents a state- wise production of bauxite in the country during 2002-03.
Orissa-Orissa, with 55.29 per cent of the total bauxite deposits, presently contributes 50.2 per cent of the total bauxite production of the country. The Bauxite belt (length 300 km, width 40-100 km, thickness (950-1300 m) of Kalahandi and Koraput districts, which continues in Andhra Pradesh, is the largest bauxite bearing region of the country. These deposits belonging to Khondolite series contain 42- 59 per cent of alumina, 7-27% of iron, and 1.3 to 7.5 percent of titanium.
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Important mining areas include Chandgiri, Baphalimali Parbat, Kathakal, Manjimali, Pasangmali, Kunnumali, Ko.dingamali, Pottangi and Koralput in Kalahandi and Koraput districts. The new aluminum plant at Damanjoli has helped in the exploitation of bauxite deposits in the state. A giant alumina project is being set up at Doragurha in Rayagada district by the Utkal Alumina International limited (UAIL).
Jharkhand-Jharkhand contributes 11.87 per cent of the total bauxite production of the country although its reserves are only 2.4 per cent of India’s total reserves. During seventies the state was the foremost producer of bauxite in the country (in 1977 the output being 37.47% of India).
The important deposits are located at Bagrupahar (Lohardaga area), Seradang, Pakharpat, Jardapahar, Maidanpat and Manduapat in Ranchi district; Jamirapat, Ranchongpat, Orsapat and Joradumar (Netarhat Plateau) in Palamau district; Kharagpur hills in Munger district and in Shahabad district.
The average mineral content in Ranchi district lies between 50 to 60 per cent while it is 50 to 63 per cent in Palamau district. Bauxite deposits attain a thickness of 7 m near Lohardaga. Two bauxite smelting plants have been installed at Lohardaga and Muri.
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Gujarat-with about 77 million tones of bauxite reserves Gujarat occupies second place (15.8%) amongst the bauxite-producing states of the country. These deposits occur in late rite capping over plateau basalts between the Deccan Traps and the Gaj beds and occupy a 48 km long and 3.2 to 4.8 km wide belt between the Gulf of Kachchh and the Arabian Sea through Bhavnagar,Junagadh and Amreli districts.
The importantdeposits are located in Mandvi, Lakhpat, Nakharana, Bhuj and Anjar talukas of Kachchh district; near Bhatia, Kenedi, Lamba,Nandana, Mewasa, Virpurand Habardi in Jamnagar district; near Harsal in Sabarkantha district; near Kapadvaj and Tayabur in Kairadistrict; and between Arjai and Pathri in Surat district.
Maharashtra-Maharashtra accounts for 3.79 per cent of the total reserves and 9.86 per cent of the total production of bauxite in the country. Here bauxite deposits mainly occur in Ratnagiri, Kolhapur, Thane, Satara and Kolaba districts of the state. Udgeri, Dhangarwadi, Radhanagari and Iderganj in Kolhapur district contain rich bauxite deposits with alumina content between 52 and 89 per cent. Similarly high-grade deposit with 62.7 per cent A1203 content has been located at Umbershet in Ratnagiri district. Sizable deposits of fairly good quality of bauxite (orecontent 51 -62 percent) have been found near Velas, Nandgaon and Supergun.
Madhya Pradesh – Chhattisgarh-the total reserves of bauxite in Madhya Pradesh (including Chhattisgarh) are estimated at 145 million tones or 5.97 per cent of the country’s total. In 2002-03 the states produced 8.34 lakh tonnes of bauxite (8.53% of all-India production).
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There are three important bauxite producing areas in the state: (i) Amarkantak plateau comprising Sarguja, Raigarh and Bilaspur districts; (ii) the Maikal range in Shahdol, Durg, Mandla and Balaghat districts; and (iii) Katni area of Jabalpurdistrict. Amarkantak region alone has bauxite reserves of 60 million tones with alumina content from 50to 60 percent. In Katni areabauxitecappings are found over sandstone and quartzite rocks with estimated reserves of 34 million tons; 80 per cent of which have high grade ore content (50-60 per cent alumina).
Significant deposits of bauxite occur on the northern part of Jamirapat plateau; on Manipat in the catchment area of the Rehar and lb rivers; on the Sarguja-Jashpur borders; and at Kumakel and Jarang Pat in Sarguja district. In Bilaspur district bauxite deposits are located on Phutka Pahar, Laddhi Pahar, Mahadeo Pahar and various hill tops.
In Shahdol and Mandla districts important deposits occur in Umergaon, Jamuna Dadar, Rakti Dadar and Nanku Dadar areas. Bauxite deposits segregated in the laterite cappings are found in Jashpur area in Khuria highlands north of Kurki, Kesmanda, Chandra and Rabbon Dan wahi. Scattered deposits of bauxite have also been found in the Bailadila Range in Bastar district; Kawardha tahsil of Durg district and several localities in Satna, Shivpuri and Guna districts.
Tamil Nadu-In Tamil Nadu bauxite depoits are mainly found in four areas : (i) in Kotagiii and [ Curzon valley areas, and near Ootacamund in the eastern portion of the Nilgiri hills; (ii) plateau region of the Palni and Kodaikanal hills in the Madurai district; (iii) Shevaroy hills near Yarcaud in Salem district; and (iv) in Killaimalai hills. The state’s total reserves are estimated at 85.8 lakh tones which I yielded at total production of 2, 68,000 tones of bauxite in 2002-03.
Goa-Bauxite deposits lie over a narrow strip of meta-basalt in Quepem and Canacona Talukas of the state with total estimated reserves at 28 million tons (alumina content being 50 per cent). The L state’s production amounted to 52,000 tons in 2002-03 which indicates more than three times in- I crease during last two decades.
Karnataka-Bauxite reserves of Karnataka 1 are estimated at 28 million tonnes yielding an annual I production of 30,000 tonnes (in 2002-03). The principal deposits occur near Doddahera area in Dakshina I Kannada district and in the north-western parts of I Belgaum district, particularly at Karle hills, Jamboti, Boknur-Navge ridge, Kiniyeand Kirvale. Patchesof bauxite has also been found near Kemmangundi, Dhupadgiri and Kahatagiri in Bababudan Hills
Andhra Pradesh-Bauxite deposits of Andhra Pradesh are the continuation from the Kalahandi- Koraput region of Orissa. Chintapalli-Saparia, Galikonda, Raktakona and Chitragondi areas of Vishakhapatnam district contain rich bauxite deposits with estimated reserves at 400 million tones. Hence, the Anontagiri plateau region of the state is going to be an important bauxite mining region of the country in near future.
Jammu and Kashmir-Deposits of high grade bauxite (70-80% alumina) occur near Khander and Thakalia in Punch district; at Chakar, Sangar Marg, Jangalgah, Sukhwalgali, Panhasa, Chahapasari and Salal Fort Hill in Rajauri and Udhampur districts. The reserves are estimated at about 11.6 million tones. Uttar Pradesh-In Uttar Pradesh bauxite deposits have been found near Dagrahin, Turkaha, Chhachhat, Ransajahi and Hasria area in Banda district (alumina content 40-60 per cent; thickness 5- 10 m). Some deposits also occur in Mirzapur, Sonbhadra, Allahabad and Varanasi districts. The total estimated reserves of the state are at 10 million tones.
Consumption and Trade
About SO per cent of the bauxite is utilised in the production of aluminium. In 1947 there were two aluminum plants located at Alwaye (Kerala) and Asansol (West Bengal) with annual installed capacity of 7,000 tones.
Since then eight new plants have been set up; 4 each in private and public sectors. Private sector companies are located at Hirakud (Orissa), Belgaum (Karnataka), Renukoot (Uttar Pradesh) and Mettur (Tamil Nadu); while Korba (Madhya Pradesh), Ratnagiri (Maharashtra), Damanjodi (Orissa) and Bhuj (Gujarat) plants lie in public sector. A giant plant has been planned by UAIL at Doragurha (Rayagada) in Orissa.
India exports small quantities of bauxite to many countries, particularly to Italy (60%), United Kingdom (25%), Germany (9%), and Japan 4%). In 1976 the value of exports was Rs. 37.59 crore which rose to Rs. 83 crore in 1980. The public sector undertaking NALCO has fixed up target to export 4.25 lakh tones of alumina and 60 thousand tones of aluminium during 1998-99 (Hindu Survey of Indian Industry, 1998, p.261).