Volume 24 / No. 1 / 1994
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Volume 24 No. 1. January 1994 The Journal of Gemmology The Gemmological Association and Gem Testing Laboratory of Great Britain OFFICERS AND COUNCIL Past Presidents: Sir Henry Miers, MA, D.Sc, FRS Sir William Bragg, OM, KBE, FRS Dr. G.F. Herbert Smith, CBE, MA, D.Sc. Sir Lawrence Bragg, CH, OBE, MC, B.Sc, FRS Sir Frank Claringbull, Ph.D., F.Inst.P., FGS Vice-Presidents: R. K. Mitchell A.E. Farn D.G. Kent E. M. Bruton Council of Management C.R. Cavey T.J. Davidson N.W. Deeks E.C. Emms I. Thomson V.P. Watson R.R. Harding Members' Council A. J. Allnutt J. Kessler R. Shepherd P. J. E.Daly G. Monnickendam R. Velden P. Dwyer-Hickey L. Music D. Warren R. Fuller, J.B. Nelson CH. Winter B. Jackson P. G. Read G.H. Jones I. Roberts Branch Chairmen: Midlands Branch: D.M. Larcher, North-West Branch: I. Knight Examiners: A. J. Allnutt, M.Sc, Ph.D., FGA G. H. Jones, B.Sc, Ph.D., FGA L. Bartlett, B.Sc, M.Phil., FGA, DGA D. G. Kent, FGA E. M. Bruton, FGA, DGA R. D. Ross, B.Sc, FGA C. R. Cavey, FGA P. Sadler, B.Sc, FGS, FGA, DGA S. Coelho, B.Sc, FGA, DGA E. Stern, FGA, DGA A.T. Collins, B.Sc, Ph.D Prof. I.Sunagawa, D.Sc. B. Jackson, FGA M. Tilley, GG, FGA E. A. Jobbins, B.Sc, C. Eng., FIMM, FGA C. Woodward, B.Sc, FGA, DGA Editor: E. A. Jobbins Production Editor: Mary A. Burland The Gemmological Association and Gem Testing Laboratory of Great Britain 27 Greville Street, London EC1N 8SU Telephone: 071-404 3334 Fax: 071-404 8843 TheJournal of Gemmology VOLUME 24 NUMBER ONE JANUARY 1994 Cover Picture Ruby crystals from Mong Hsu, Myanmar (Burma): the terminated crystal (9mm high) is not heat treated. The hexagonal blue zoning characteristic of natural (not heat treated) Mong Hsu ruby rough is prominently visible in this partly polished crystal fragment (7mm across) on the lower left, while the view on the lower right is the same crystal after heat treatment at 1350°C in an oxidizing atmosphere for seven hours (see 'Myanmar and its gems - an update' p.3) Upper photo by Shane F. McClure and lower photos by John L. Emmett. Crystals courtesy of Robert E. Kane. ISSN: 0022-1252 2 J. Gemm., 1994/24,1 STUDENT STARTER SET AN IDEAL STARTER SET FOR ALL STUDENTS OF GEMMOLOGY THIS SET INCLUDES: 18mm 10x Loupe (available in chrome or matt black finish) Medium Stone Tongs Chelsea Colour Filter OPL Spectroscope SPECIAL INTRODUCTORY PRICE £60.00 plus VAT, postage and packing Normal Retail Price £66.95 plus VAT, postage and packing GAGTL members receive an additional 10% discount on the Special Introductory Price To order your set please use the order form following p.48 (Please quote your membership number when placing an order) Gemmological Instruments Limited • FIRST FLOOR, 27 GREVILLE STREET, (SAFFRON HILL ENTRANCE), LONDON ECl N 8SU • Tel: 071 404 3334 Fax: 071 404 8843 J. Gemm., 1994, 24, 1 3 Myanmar* and its gems - an update Robert C. Kammerling1, Kenneth Scarratt2, George Bosshart3, E. Alan Jobbins4, Robert E. Kane5, Edward J. Gübelin6 and Alfred A. Levinson7 1. GIA Gem Trade Laboratory, Santa Monica, USA 2. AIGS, Bangkok, Thailand 3. Gübelin Gemmological Laboratory, Lucerne, Switzerland 4. Caterham, UK 5. Lake Tahoe, USA 6. Lucerne, Switzerland 7. University of Calgary, Alberta, Canada Fig. 1. The Kingdoms of Pagan in central Myanmar go back almost to the beginning of the Christian era, but the golden periods during the eleventh and twelfth centuries saw an extraordinary explosion of building which resulted in many hundreds of temples and pagodas (many now in ruins) squeezed into an area of only around 40 sq. km. Photo by E.A. Jobbins Abstract Introduction This paper up-dates and expands upon the It is clear that over the past three years more information contained in Kane and Kammerling information has become available about the (1992) in relation to the gemstone production in current operations of the Myanma Gems the area of Mogok and goes further in that it Enterprise (MGE) and its joint-ventures. This relates the information gained on other impor follows a period that has lasted from the early tant producing areas within Myanmar during 1960s in which little was revealed to the outside several visits to the country by the majority of the world about any gemstone production, prospect authors. However, many of the areas referred to ing, or any other related research that was being still remain unvisited by the non-Burmese and carried out in Myanmar [note: both Myanmar the information contained here is a compilation and Burma are used interchangeably throughout of published data and verbal information gained this paper depending upon historic preference]. both within and without Myanmar. One of the first indications of the increase in the availability of information was the paper pub Key words: Burma, gemstones, geology, lished by Kane and Kammerling (1992) entitled Myanmar Status of ruby and sapphire mining in the Mogok Stone Tract. ^Myanmar - formerly Burma © Copyright the Gemmological Association ISSN: 0022-1252 4 J. Gemm., 1994, 24,1 The situation in Myanmar is such that certain mines near Mogok', so stated Gordon (1888) at a areas remain within the designation 'not recom meeting of the Royal Geographical Society held mended for travel', a warning that westerners on the evening of 27 February 1888. His report would be most unwise to disregard. Certainly published in the proceedings of that meeting, the country is rugged and there is a need for goes on to state that a concession was granted to expert guides. The survey map (Figure 2) shows Messrs Streeter & Co. of London. He also reports the positions of the diamond and jade deposits in that he was asked to survey and report on the the north, through the corundum deposits in the mining district by the concessionaires. The map Mogok area (Figure 3) and the diamond deposits he produced at the time shows the Mogok area in and pearl farms in the south. great detail with even at that time a considerable Myanmar's gemstone wealth is set out in Table amount of cultivated land. 1 in the form of 'Economically important gem- Gordon's report for the period he spent sur stones', 'Economically less important gemstones' veying the ruby deposits is probably the most and 'Rare gemstones'. Table 1 reads like the useful of its type for evaluating the differences index to a gemmological textbook, with very few that have occurred over the last 100 years. He stones missing, and this attests to the enormous describes not only the mines and mining gemstone wealth possessed by this country. methods in simple terms but also the inhabitants of the numerous villages in the area. He states History that in this period the mines were of three types, Myanmar (Burma) is regarded as one of the the first, which was the least important at that earliest sources of fine rubies, sapphires and time, consisted of spinels. Mining was first recorded in the sixth 'working in fissure veins of soft material which century (Chhibber, 1934). These gemstones con are found embedded in the crevices of hard rock. tinued to be mined through the centuries with ... The crevices in the older rocks give origin to the Monarchy taking control of the mines cave mines, which are called "Loos" [also known towards the end of the sixteenth century. A as "loodwins"] where the soft earth is excavated number of historically important stones may be in a primitive fashion and on a small scale. ... dated back to this period. Indeed, Burmese Pingu-toung, a steep hill overlooking Bama (spelt rubies, sapphires and spinels have been set in Panma in Figure 3), is rich in such mines. royal regalia and aristocratic jewellery for many 'The second class of mine is called "Myaw" centuries and probably back to the sixth century. [also known as "Hmyawdwins"] or washing. Some of these important stones figure promi The clay is cut into thin slices with a gardener's nently in several of the treasures in the royal spade and washed from the funnel shaped exca regalia of a number of countries, including vations through the flumes or open timber England. Two of the authors have recently channels, where the clay is dissolved away, or enjoyed the privilege of examining most of the carefully examined for the stones.' historic English Royal Regalia which is housed in The third and most important at that time was the Tower of London. Possibly the earliest stone the class of mines found in the flatter lands of the is the Black Prince's Ruby (actually an orange-red valleys. These were referred to as 'twinlons' spinel) which can, with a reasonable degree of (narrow circular pits) and their variants the certainty, be dated back to 1367. This large spinel Tebins' (reinforced pits) which were normally is set in the front of the Imperial State Crown. only 60cm wide, the 'cobin' 1 to 1.5m deep and From its properties and inclusions it would the 'imbye' 6 to 9m deep (Chikayama, 1987,9,4). appear to be of Burmese origin. The Timur Ruby At depths varying from 3 to 9 metres there is (also a spinel) in the British Royal collection found a layer of corundum from a few centime would also appear to be of Burmese origin. tres to a few metres in thickness. Superb rubies with Burmese characteristics are Messrs Streeter & Co. formed the Burma Ruby liberally distributed in the various coronation Mines Ltd.