Key reserve profiles of placer deposits: Chavara and Manavalakurichi (From Ph.D. thesis of Ajith G. Nair, 2001)
STUDIES ON ILMENITE OF CHAVARA AND MANAVALAKURICHI DEPOSITS, SOUTHWEST COAST OF INDIA (Ph.D. Thesis of Ajith G. Nair, School of Marine Sciences, Cochin University of Science and Technology, Cochin, June 2001). Source: Dyuthi-T0031.pdf
NOTE: Ilmenite placer deposits can contain 1–2 per cent monazite.(Möller, 1986)
The placer deposits encompass a wide range of minerals having varying specific gravity…(1) heavy heavy minerals with specific gravity between 6.8 and 21. eg: native gold, cassiterite etc., (2) light heavy minerals with specific gravity between 4.2 and 5.3. eg: ilmenite, rutile, monazite, zircon, and (3) those with densities falling between 2.9 -4.1. eg: garnet, sillimanite, hypersthene etc. (p.1)
Beach placers: Such placers are formed by the interacton of the terrestrial processes with the coastal hydrodynamics. The heavy minerals among the sediments, that are contributed to the sea by various processes of transportation are selectively panned and sorted and then
deposited at suitable locations, by the action of waves and currents. The factors controlling the formation of beach placers are geomorphology of the area, climate, drainage pattern, coastal processes, neotectonics etc. (p.2)
The history of placer deposits as a source of economic minerals began with the discovery of monazite in the beach sands of Manavalakurichi (Tipper, 1909). This was first worked in 1911 and rapidly developed with the establishment of Ti02 (titania) pigment industry in Europe and America. In early 1930's, India accounted for 80% of the total ilmenite
production in the world. (p.4)
The current reserves of the placer minerals in India, are as follows; 278 million tonnes (MT) of ilmenite 13.49 MT of rutile, 18 MT of zircon, 7 MT of monazite, 84 MT of sillimanite and 86 MT of garnet (AMD, 2000). The major placer concentrations of India are located along the east and west coasts.(p.5)
Chavara Deposit. This deposit, popularly known as Quilon deposit is one of the largest and richest in the world. It extends to about 22 km with a width of around 500m. It stretches as a barrier beach between Neendakara, at the mouth of Ashtamudi estuary and Kayamkulam. The deposit has a maximum depth of ISm and is estimated to contain about 12.7 MTof ilmenite, 1 MT of rutile, 1.9 MT of zircon and 0.41 MT of monazite and 6 MT of sillimanite (Fig. 1.2)… The total average content of heavy minerals is around 390/0. Of these,
ilmenite forms the major constituent (24%), with rutile (1.8°A», leucoxene
(0.90/
0), zircon (20/0), monazite (1%), sillimanite (3.5%) and garnet (5.5%).
Ilmenite contains about 560/0 Ti02. The monazite has a total of 58% REE
oxides and 8% Th02. The total reserves of heavy minerals in the
Manavalakurichi-Kolachel stretch are estimated to be about 1.6MT. Ilmenite amounts to about 1 MT. The reserves of other minerals estimated are as follows): 0.075 MT of rutile, 0.035 MT of leucoxene, 0.082 MT of zircon, 0.043 MT of monazite, 0.23 MT of garnet, 0.14 MT of sillimanite and about 6850 tonnes' of kyanite. The area north of Kolachel to Midalam has been found to contain workable deposits of heavy minerals estimated to about 0.5 MT. The reserves of ilmenite and rutile are worked out to be around 0.31 MT ani 15,300 tonnes respectively (p.6)
Manavalakurichi Deposit. It is located in the Kanyakumari district of Tamil Nadu. It is one of the oldest known deposits, which was first worked for its monazite. The deposit extends to a length of about 6 km, from the north of Muttom promontory to Kolachel, with an average width of 45m (Fig. 1.3).(p.8)
Teri sands of Tamil Nadu. These inland deposits occur along parts of south eastern coast of Tamil Nadu in the form of Teris in parts of Tirunelveli, Chidambranagar, Ramanathapuram districts. They standout prominently in the area, at' elevations of 3D-60 m. They occur as widely separated isolated patches with dimensions ranging from a few hectares to about 6000 hectares. They are found about 0.1-10 km inland from the beach placers in a semi arid setting. Seven such deposits with an aggregate area of 144 km have been identified (Krishnan et aI, 1994). They are NavaladiPeriathalai, Kudiraimoli, Sattankulam, Kuttampuli, Surangudi, Kilakarai and Kulathur with heavy mineral concentration ranging from 617°1'<>. The average mineral grade is about 10% with reserves of 123 MT (AMD, 2000). The split up of the total reserves are as follows, 77.2 MT of ilmenite, 4.03 MT of rutile, 3.9 MT of leucoxene, 7.07 MT of zircon, 1.2 MT of monazite, 12MT of garnet and 17 MT of sillimanite. The Sattankulam and Kudiraimoli deposits have reserves of about 22 and
13 MT of total heavy minerals respectively. While Sattankulam area contains about 14.3 MT of ilmenite, 1.4 MT of rutile, 1.1 MT of leucoxene, 0.96 MT of zircon, 0.21 MT of monazite and 4.3 MT of sillimanite, the Kudiraimoli deposit contain estimated reserves of minerals as follows: 9.3 MT of ilmenite , 0.63 MT of rutile, 0.38 MT of leucoxene, 0.46 MT of zircon, 0.11 MT of garnet and 1.9 MT of sillimanite (p.9)
Chatarpur Deposit. This deposit falls in the Ganjam district of Orissa near Gopalpur. It extends to a length of 22 km with an average width of 1.54 km. The average grade of the heavy mineral is about 20% with ilmenite (8.800/0), rutile (0.38%), monazite (0.27%), garnet (6.700/0), zircon (0.31%) and sillimanite (3.400/0). The total reserves are estimated to be 46.61 MT with a grade of about 20.22% (Ali et al, 1998). Of these, ilmenite constitutes
about 20.3 MT. The. assay ofTiQ in ilmenite is around 50%. (p.10)
Indian Rare Earths: The Indian Rare Earths Ltd. has plants in Quilon (Kerala), Manavalakurichi (Tamil Nadu) and Chatrapur (Orissa), in addition to a Rare Earth plant at Alwaye. The current capacity of the Quilon plant is 13,00,00 tons of ilmenite./year. Though the Chatrapur plant was commissioned with a planned capacity of 220,000 tons/year, due to certain technical problems involved in the processing of the Orissa ilmenite, the production at present is not up to the expected levels, though synthetic rutile is produced at a rate of 25,000 m. tons/year. (p.23)
NOTE: Ilmenite placer deposits can contain 1–2 per cent monazite.(Möller, 1986)
The placer deposits encompass a wide range of minerals having varying specific gravity…(1) heavy heavy minerals with specific gravity between 6.8 and 21. eg: native gold, cassiterite etc., (2) light heavy minerals with specific gravity between 4.2 and 5.3. eg: ilmenite, rutile, monazite, zircon, and (3) those with densities falling between 2.9 -4.1. eg: garnet, sillimanite, hypersthene etc. (p.1)
Beach placers: Such placers are formed by the interacton of the terrestrial processes with the coastal hydrodynamics. The heavy minerals among the sediments, that are contributed to the sea by various processes of transportation are selectively panned and sorted and then
deposited at suitable locations, by the action of waves and currents. The factors controlling the formation of beach placers are geomorphology of the area, climate, drainage pattern, coastal processes, neotectonics etc. (p.2)
The history of placer deposits as a source of economic minerals began with the discovery of monazite in the beach sands of Manavalakurichi (Tipper, 1909). This was first worked in 1911 and rapidly developed with the establishment of Ti02 (titania) pigment industry in Europe and America. In early 1930's, India accounted for 80% of the total ilmenite
production in the world. (p.4)
The current reserves of the placer minerals in India, are as follows; 278 million tonnes (MT) of ilmenite 13.49 MT of rutile, 18 MT of zircon, 7 MT of monazite, 84 MT of sillimanite and 86 MT of garnet (AMD, 2000). The major placer concentrations of India are located along the east and west coasts.(p.5)
Chavara Deposit. This deposit, popularly known as Quilon deposit is one of the largest and richest in the world. It extends to about 22 km with a width of around 500m. It stretches as a barrier beach between Neendakara, at the mouth of Ashtamudi estuary and Kayamkulam. The deposit has a maximum depth of ISm and is estimated to contain about 12.7 MTof ilmenite, 1 MT of rutile, 1.9 MT of zircon and 0.41 MT of monazite and 6 MT of sillimanite (Fig. 1.2)… The total average content of heavy minerals is around 390/0. Of these,
ilmenite forms the major constituent (24%), with rutile (1.8°A», leucoxene
(0.90/
0), zircon (20/0), monazite (1%), sillimanite (3.5%) and garnet (5.5%).
Ilmenite contains about 560/0 Ti02. The monazite has a total of 58% REE
oxides and 8% Th02. The total reserves of heavy minerals in the
Manavalakurichi-Kolachel stretch are estimated to be about 1.6MT. Ilmenite amounts to about 1 MT. The reserves of other minerals estimated are as follows): 0.075 MT of rutile, 0.035 MT of leucoxene, 0.082 MT of zircon, 0.043 MT of monazite, 0.23 MT of garnet, 0.14 MT of sillimanite and about 6850 tonnes' of kyanite. The area north of Kolachel to Midalam has been found to contain workable deposits of heavy minerals estimated to about 0.5 MT. The reserves of ilmenite and rutile are worked out to be around 0.31 MT ani 15,300 tonnes respectively (p.6)
Manavalakurichi Deposit. It is located in the Kanyakumari district of Tamil Nadu. It is one of the oldest known deposits, which was first worked for its monazite. The deposit extends to a length of about 6 km, from the north of Muttom promontory to Kolachel, with an average width of 45m (Fig. 1.3).(p.8)
Teri sands of Tamil Nadu. These inland deposits occur along parts of south eastern coast of Tamil Nadu in the form of Teris in parts of Tirunelveli, Chidambranagar, Ramanathapuram districts. They standout prominently in the area, at' elevations of 3D-60 m. They occur as widely separated isolated patches with dimensions ranging from a few hectares to about 6000 hectares. They are found about 0.1-10 km inland from the beach placers in a semi arid setting. Seven such deposits with an aggregate area of 144 km have been identified (Krishnan et aI, 1994). They are NavaladiPeriathalai, Kudiraimoli, Sattankulam, Kuttampuli, Surangudi, Kilakarai and Kulathur with heavy mineral concentration ranging from 617°1'<>. The average mineral grade is about 10% with reserves of 123 MT (AMD, 2000). The split up of the total reserves are as follows, 77.2 MT of ilmenite, 4.03 MT of rutile, 3.9 MT of leucoxene, 7.07 MT of zircon, 1.2 MT of monazite, 12MT of garnet and 17 MT of sillimanite. The Sattankulam and Kudiraimoli deposits have reserves of about 22 and
13 MT of total heavy minerals respectively. While Sattankulam area contains about 14.3 MT of ilmenite, 1.4 MT of rutile, 1.1 MT of leucoxene, 0.96 MT of zircon, 0.21 MT of monazite and 4.3 MT of sillimanite, the Kudiraimoli deposit contain estimated reserves of minerals as follows: 9.3 MT of ilmenite , 0.63 MT of rutile, 0.38 MT of leucoxene, 0.46 MT of zircon, 0.11 MT of garnet and 1.9 MT of sillimanite (p.9)
Chatarpur Deposit. This deposit falls in the Ganjam district of Orissa near Gopalpur. It extends to a length of 22 km with an average width of 1.54 km. The average grade of the heavy mineral is about 20% with ilmenite (8.800/0), rutile (0.38%), monazite (0.27%), garnet (6.700/0), zircon (0.31%) and sillimanite (3.400/0). The total reserves are estimated to be 46.61 MT with a grade of about 20.22% (Ali et al, 1998). Of these, ilmenite constitutes
about 20.3 MT. The. assay ofTiQ in ilmenite is around 50%. (p.10)
Indian Rare Earths: The Indian Rare Earths Ltd. has plants in Quilon (Kerala), Manavalakurichi (Tamil Nadu) and Chatrapur (Orissa), in addition to a Rare Earth plant at Alwaye. The current capacity of the Quilon plant is 13,00,00 tons of ilmenite./year. Though the Chatrapur plant was commissioned with a planned capacity of 220,000 tons/year, due to certain technical problems involved in the processing of the Orissa ilmenite, the production at present is not up to the expected levels, though synthetic rutile is produced at a rate of 25,000 m. tons/year. (p.23)
No comments:
Post a Comment