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CORUNDUM AND

Indian Yearbook 2018 (Part- III : Reviews)

57th Edition

MINOR MINERALS

30.4 CORUNDUM (Minor) AND SAPPHIRE (Major)

(FINAL RELEASE)

GOVERNMENT OF INDIA MINISTRY OF MINES INDIAN BUREAU OF MINES

Indira Bhavan, Civil Lines, NAGPUR – 440 001

PHONE/FAX NO. (0712) 2565471 PBX : (0712) 2562649, 2560544, 2560648 E-MAIL : [email protected] Website: www.ibm.gov.in

June, 2019

30-4-1 CORUNDUM AND SAPPHIRE 30-4 Corundum and Sapphire

orundum is a natural of alumina with Telangana. A few outcrops of C52.9% alumina and 47.1% . It is very containing corundum occur in Bastar district, hard (9 on Moh's scale) following diamond. Chhattisgarh and Morena district, Madhya Corundum is found in rocks containing a high Pradesh. Translucent to opaque , sometimes percentage of alkalies, deficient in silica and with asterism is known to be abundant in Mysuru excess of alumina. It is generally found in district in Karnataka. association with rocks like syenite, nepheline Precious and semi-precious varieties of syenite, anorthosite. Described to be formed as a corundum have been reported from Tamil Nadu in result of metamorphism of high aluminous clay, Kangeyam belt stretching over Karur and corundum is often found associated with Kulithalai tehsils in Tiruchirapalli district and andalusite, and sillimanite. Corundum Vedachandur tehsil in Dindigul district. also occurs as masses adjacent to ultramafic intrusives, associated with dykes As per NMI data as on 1.4.2015 based on and as large in pegmatites. The most UNFC Sytem, the total reserves/resources of common occurrence of corundum would be as a corundum was estimated at 294 thousand tonnes detrital mineral in streams and beach sands of which 200 tonnes were placed under Reserves because of its hardness and resistance to category and the bulk of over 293 thousand weathering. Pure corundum is colourless and clear tonnes under 'Remaining Resources' category. The if transparent or pale white if opaque. The vivid resources of corundum are located in Karnataka colours of corundum gem varieties such as ruby (68%), Telangana (26%) and Rajasthan (4%), and sapphire arise primarily from elemental besides a share of the Remaining Resources was substitution in the Al site by contributed by Tamil Nadu, Chhattisgarh and elements. The most common cations found as Andhra Pradesh. +2 +3 +4 +3 +3 substitute are Fe , Fe , Ti , Cr and V . Pink The total reserves/resources of ruby as on and red colour corundum are called ruby while 1.4.2015 was estimated at 5,349 kg and the entire blue coloured corundum is called sapphire and all resources are placed under 'Remaining Resources' other colours are called fancy . Usually category and are located in Odisha. The total will have more or less 1 wt% of Cr O while 2 3 reserves/resources of sapphire was estimated at +2 +4 blue sapphires primarily have Fe and Ti 450 kg, all of which is placed under 'Remaining substituting into the structure of Al. Some Resources' category and is located in Jammu & corundum show "asterism" or a star Kashmir [Tables - 1(A) to 1(C)]. effect due to inclusion of rutile needles within the crystal of corundum. EXPLORATION AND RESERVES/RESOURCES DEVELOPMENT

The reserves/resources of corundum in India The exploration & development details, if any, are found in association with kyanite and are given in the review on "Exploration & sillimanite in Assam, Meghalaya and Maharashtra. Development" in "General Reviews". It occurs in syenites and ultrabasic rocks in

30-4-2 CORUNDUM AND SAPPHIRE 4 930 207 885 2758 4000 Total 26997 11925 77113 (A+B) 293697 263007 199566 Resources (In tonnes) 4 7 930 885 2558 4000 (B) Total 26997 11925 77113 293497 263007 199566 ------52675 52675 52675 STD334 Reconnaissance - 4 895 288 2533 4000 90479 11883 27575 11925 62007 105794 Inferred STD333 ------1 1 8 3 8 2 8 3 8 STD332 Indicated ------1 3 1 3 1 3 Remaining Resources STD331 Measured - - - - - 1 1 188 9282 9282 63060 53767 53590 STD222 ------7 3 4 310 756 Pre-feasibility 1073 1039 STD221 ------(ByGrades/States) 100 5824 5824 70844 65020 64920 STD211 Feasibility ------(A) Total 200 200 200 ------STD122 Table– 1(A):Reserves/Resources of Corundum as on 1.4.2015 Reserves Probable ------STD121 ------200 200 200 Proved STD111 : " - " Nil Note Figures rounded off. Grade/State All India : Total By Grades Semi-precious Industrial Others Unclassified Not-known By States Andhra Pradesh Chhattisgarh Karnataka Rajasthan Tamil Nadu Telangana

30-4-3 CORUNDUM AND SAPPHIRE 450 450 450 5349 5349 5349 (In kg) (In kg) Total Total (A+B) (A+B) Resources Resources 450 450 450 (B) (B) 5349 5349 5349 Total Total ------STD334 STD334 Reconnaissance Reconnaissance 450 450 450 1623 1623 1623 Inferred Inferred STD333 STD333 ------STD332 STD332 Indicated Indicated ------Remaining Resources Remaining Resources STD331 STD331 Measured Measured - - - 3296 3296 3296 STD222 STD222 - - - Pre-feasibility 429 429 429 Pre-feasibility STD221 STD221 ------(ByGrade/State) (ByGrades/States) STD211 STD211 Feasibility Feasibility ------(A) (A) Total Total ------Table– 1(B): Reserves/Resources of Ruby as on1.4.2015 STD122 STD122 Table– 1(C):Reserves/Resources of Sapphire as on1.4.2015 Reserves Probable Reserves Probable ------STD121 STD121 ------Proved Proved STD111 STD111 : " - " Nil : " - " Nil Note Note Grade/State Grade/State All India : Total By Grade Unclassified By State Jammu & Kashmir Figures rounded off. Figures rounded off. All India : Total By Grade Unclassified By State Odisha

30-4-4 CORUNDUM AND SAPPHIRE

PRODUCTION significant producer of corundum, especially in Madagascar, where it is found in the Zazafotsy CORUNDUM Quarry, Ambahatraso; and in Andranondambo, As per Govt. of India Notification S.O. 423(E), Amboasary District. Rubies are found in Longido, dated 10th February 2015, 'Corundum' has been Kilimanjaro Region and Winza, in Arusha area, declared as 'Minor Mineral', hence the producers Tanzania. In the US, the Yogo Gulch near Helena report the production data directly to the respective and waterworn Sapphire stones are found in the states and not to IBM. However, 'Sapphire' has been Missouri river throughout its length. retained as Major Mineral. State-wise production of The area of Mogok, Myanmar is the source of corundum and sapphire is not available. some of the best gem-quality ruby. Another RUBY significant Burmese deposit is Mong Hsu. There was no production of ruby reported for the years 2015-16 and 2016-17. FOREIGN TRADE Export value of uncut ruby and sapphire CONSUMPTION & USES increased to ` 58.62 crore in 2017-18 as compared It is valued mostly for its and to ` 38.99 crore in 2016-17. Exports were mainly to refractory properties. Its is 2010 oC and Singapore (83%), Hong Kong (9%) and Thailand hence it is used in a sintered form for the (5%) (Table - 2). manufacture of special refractory crucibles, rods and Imports of uncut ruby and sapphire increased other materials. substantially to 29 tonnes valued at ` 2478.59 Corundum's bright and glassy , splintery crore in 2017-18 from 11 tonnes, valued at property as it is devoid of plane and ` 1166.65 crore in 2016-17. Imports were mainly inclusions makes it preferred substance by industry from Hong Kong (64%), UAE (16%), Madagascar for the manufacture of superior grade . (9%) and Mozambique (4%) (Table - 3). After processing, it is used in grinding and polish- No trading of cut ruby and sapphire was ing wheels, grinding belts, emery papers and cloth reported during 2016-17 and 2017-18 and grinding pastes. High-grade corundum with low finds use as ramming mass in the electric arc Table-2: Exports of Ruby and Sapphire: Uncut furnace. It is also used in mortars, wire drawing dies, (By Countries) thread guides and gauge blocks. Gem varieties are sometimes used for pivot supporters in delicate 2016-17 2017-18 (P) Country scientific instruments, as jewel in . Sapphire Qty Value Qty Value has emerged as a versatile material useful to a range (t) (`'000) (t) (`'000) of industries in many varied applications including All Countries ++ 389887 3 586210 LEDs, optical and Radio Frequency Integrated Singapore ++ 287986 ++ 486513 Circuits (RFICS). Hong Kong ++ 31870 1 52370 WORLD SCENARIO Thailand ++ 13590 2 26620 ChineseTaipei/ - - ++ 9703 Corundum & sapphire are reported from Taiwan Sri Lanka, especially from the area of Ratnapura, USA ++ 1937 ++ 2754 Bibile and Rakwana. Ruby with a brownish tint Switzerland ++ 19031 ++ 2542 comes from Chanthaburi district in Thailand. Fine Israel ++ 959 ++ 1460 gem ruby and sapphire come from Luc Yen, Japan - - ++ 1009 Yen Bai Province, Vietnam; the Hunza Valley, Gilgit, UAE ++ 5488 ++ 969 Pakistan; and Jegdalek, Surobi district, Afghanistan. Gem quality sapphire is reported Hungary - - ++ 573 from Pailin, Cambodia. Africa has also become a Other countries ++ 29026 ++ 1697 Note : '++' Negligible, ' - ' Nil

30-4-5 CORUNDUM AND SAPPHIRE Table-3: Imports of Ruby and Sapphire: Uncut FUTURE OUTLOOK (By Countries) Corundum has been produced synthetically 2016-17 2017-18 (P) since 1837 and gem quality of synthetic corundum Country entered the market place in the early 1990's. Very large Qty Value Qty Value sizes of crystals can be made by Czochralski's (t) (`'000) (t) (`'000) Drawing Method. Another method is Verneuil All Countries 11 11666479 2 9 24785905 process but synthetic gem variety can be recognised

Hong Kong 8 8596582 9 15844102 by trained gemologist. The market for synthetic corundum is mainly driven by industrial abrasion UAE ++ 409137 ++ 3883049 applications. The natural occurring corundum has Madagascar ++ 9 2 2214524 tremendous value in the market and is the Mozambique ++ 260684 1 1087263 most desirable precious stone after diamond.

China ++ 8 1 ++ 641602 Owing to its uncommon colours, corundum's demand in the Jewellery Segment is increasingly on the rise. Zambia 2 1626126 ++ 482811 Apart from rubies and sapphire, rare gemstones, such Thailand 1 205142 1 3 295799 as, padparadscha sapphire, witnessed expanding South Africa ++ 246584 1 202638 market demands.

Singapore ++ 85272 ++ 32406 In India, the gemstone market has been expanding. The gemstone market in India (which USA ++ 55486 ++ 26853 includes ruby & sapphire) is expected to ramp-up in Other countries ++ 181376 3 74858 coming years. Note : '++' Negligible

30-4-6