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Themmoie Journaemmoil of ^ Volumemmoie 27 No. 6 April 2001 Hte long sein Gemstoncs of Peru Gem quality clinohumite Colour of diamonds The Cemmological Association and Gem Testing Laboratory of Great Ikitain ^§ff ^ Gemmological Association Mplf and Gem Testing Laboratory HS? of Great Britain ^£5^ 27 Greville Street, London EC1N 8TN Tel: 020 7404 3334 Fax: 020 7404 8843 e-mail: [email protected] Website: www.gagtl.com President: Professor A.T. Collins Vice-Presidents: A.E. Farn, R.A. Howie, D.G. Kent, R.K. Mitchell Honorary Fellows: Chen Zhonghui, R.A. Howie, R.T. Liddicoat Jnr, K. Nassau Honorary Life Members: H. Bank, D.J. Callaghan, E.A. Jobbins, H. Tillander Council of Management: T.J. Davidson, N.W. Deeks, R.R. Harding, I. Mercer, J. Monnickendam, M.J. O'Donoghue, E. Stern, I. Thomson, J-P. van Doren, V.P. Watson Members' Council: A.J. Allnutt, P. Dwyer-Hickey, S.A. Everitt, A.G. Good, J. Greatwood, B. Jackson, L. Music, J.B. Nelson, PG. Read, P.J. Wates, C.H. Winter Branch Chairmen: Midlands - G.M. Green, North West - I. Knight, Scottish - B. Jackson, South West - R.M. Slater Examiners: A.J. Allnutt, M.Sc, Ph.D., FGA, L. Bartlett, B.Sc, M.Phil., FGA, DGA, S. Coelho, B.Sc, FGA, DGA, Prof. A.T. Collins, B.Sc, Ph.D, A.G. Good, FGA, DGA, J. Greatwood, FGA, G.M. Howe, FGA, DGA, S. Hue Williams MA, FGA, DGA, B. Jackson, FGA, DGA, G.H. Jones, B.Sc, Ph.D., FGA, Li Li Ping, FGA, DGA, M. Newton, B.Sc, D.Phil., C.J.E. Oldershaw, B.Sc. (Hons), FGA, DGA, H.L. Plumb, B.Sc, FGA, DGA, R.D. ROSS, B.Sc, FGA, DGA, P.A. Sadler, B.Sc, FGA, DGA, E. Stern, FGA, DGA, S.M. Stocklmayer, B.Sc (Hons), FGA, Prof. I. Sunagawa, D.Sc, M. Tilley, GG, FGA, CM. Woodward, B.Sc, FGA, DGA The Journal of Gemmology Editor: Dr R.R. Harding Assistant Editors: M.J. O'Donoghue, P.G. Read Associate Editors: Dr C.E.S. Arps (Leiden), G. Bosshart (Zurich), Prof. A.T. Collins (London), Dr J.W. Harris (Glasgow), Prof. R.A. Howie (Derbyshire), Dr J.M. Ogden (Hildesheim), Prof. A.H. Rankin (Kingston upon Thames), Dr J.E. Shigley (Carlsbad), Prof. D.C. Smith (Paris), E. Stern (London), Prof. I. Sunagawa (Tokyo), Dr M. Superchi (Milan), CM. Woodward (London) Production Editor: M.A. Burland Vol 27, No. 6, April 2001 ISSN: 1355-4565 Hte long sein - a new variety of chrome jadeite jade C.M. Ou Yang1 and Li Jian, Qi2 1. 26/F Tung Hip Commercial Bldg., 244-252 Des Voeux Road, Central, Hong Kong 2. China University of Geosciences, Wuhan, China ABSTRACT: A new variety of chrome-jadeite jade called 'hte long sein' is described. The origin of the name is given and the gemmological properties, chemical composition and IR spectrum described. Its main features compared with traditional jadeite jade are evenness of colour, relative coarseness of grain and opacity. Introduction where it became the major topic of conversation - especially around the Canton t the 27th Rough Auction held at the Road where the dealers have long been end of March 1999 in Yangon, Myanmar, the participants did not involved with 'traditional' jadeite. Initially, 323 A some doubted that it was jadeite jade and expect to see nearly a hundred piles of jadeite 323 rough ranging from full green to bright some gem laboratories declined to issue medium emerald green (Figures 1 and 2). It identification certificates. The influx of such was classified in two grades: Grade A a large quantity of jadeite also raised fears of material was pure in colour and fine-grained a slump in the jade market with few fractures; Grade B was more coarse so far, groundless. ly textured and contained more fractures. The quality can be classified into five grades Figure 1: Hte long sein jadeite jade in Yangon according to the colour, transparency, texture auction in 1999. and clarity. All the grades are generally called hte long sein. Hitherto, a few private dealers had sold hte long sein for quite high prices, but the floor prices for the lots at this auction were much lower and prompted the feeling that they were very good value - with comments such as 'glad tidings' and 'Gospel from Heaven7 being heard! Consequently, bidding was fierce and ran from one afternoon until 4:00 a.m. the next morning, with some bids ten times the floor price for a particular lot. In April 1999, several tonnes of full green hte long sein were shipped to Hong Kong, © Gemmological Association and Gem Testing Laboratory of Great Britain ISSN: 1355-4565 Figure 2: A lens-shaped specimen ofhte long sein jadeite jade. 323•%23t ^e Hong Kong market soon saw a wide Origin of the name 'hte long sein' variety of hte long sein full green products including carved butterflies, autumn leaves, In 1994 a primary deposit of jadeite was carved beadwork and bangles - all thin- discovered at Longkin worksite, north o323f based pieces to demonstrate the richness of Pharkant mining district, northern the colours (Figures 3 and 4). Despite the Myanmar. This jadeite had a full green misgivings of a few people, many welcomed colour and differed from the more familiar the hte long sein to stir up a jade market they green vein or white jadeite with green spots or patches. This difference led to it being likened to a pond of stagnant water! called 'hte long sein' - which means 'full green' in the local language. Later, the Chinese transliterated the name to 'tie long shen' or 'tian long sheng' which sounds close to the original Burmese. Characteristics of rough hte long sein Large-scale exploitation of the jade at Longkin started in 1997 and was jointly conducted by the Myanmar Government and private enterprise. However, production could only go to auction under the auspices of the government. The hte long sein jadeite occurs in veins Figure 3: A polished slice ofhte long sein jadeite or lens-shaped masses up to 1 m across jade. enclosed in amphibolite and the occurrences /. Gemm., 2001, 27, 6, 321-327 323323 323 323 323 Figure 4: Jewellery fashioned in hie long sein jade: (a) dragonfly; (b) flower; (c) beads; (d) butterflies. commonly display the following pattern of In general, hte long sein has a lovely zoning: bright green colour but is poor in transparency 1. core of homogeneous, fine-grained pure With this new knowledge about the green jadeite; primary deposit, it is now apparent that similar jadeite has been recovered from 2. each margin consists of jadeite with a secondary deposits for many years, but only glistening mineral resembling horn in very small amounts. blende; some veins have margins of white jadeite; Gemmological characteristics 3. country rock of black amphibole and Many Hong Kong merchants with more white plagioclase feldspar. than 20 years experience in the jade trade Hte long sein - a new variety of chrome jadeite jade 45- 40- 35- 30- 25- 15- 10- 5- . ^ —j- ... ...,vri?........ 1 120 0 110Q 1000 ^00 800 W 600 500 WaverKimb^i |^| "Figure 5: Infrared spectra of jadeite jade (blue), hte long sein jade (green), and kosmochlor jade (red). ifpi 323 consider hte long sein to differ significantly Chelsea Colour Filter: Appears green under from their traditional material, the principal the filter. visible differences being the full green colour Ultra violet radiation: inert under both long and 'looser' coarser texture. Its gemmological and short wave UV. features are summarized thus: 323 Infrared spectrum: reflectance infrared Appearance: Bright medium green in spectral measurements were made on ten different shades; some white spots, poor samples and a typical spectrum is shown in transparency; coarse to medium grained Figure 5, green trace. Pure jadeite and granular texture; the crystals have no kosmochlor spectra (blue and red traces) are preferred directional orientation but some shown for comparison, and the similarity of specimens do contain crystals with some the hte long sein and jadeite traces is evident. degree of preferred orientation. Because hte long sein is relatively opaque, its appearance Laser Raman spectrum: laser Raman can be made most attractive in pieces whose spectrum measurements were made on ten thickness is about 1 mm. samples and a typical spectrum is shown in Figure 6, trace 2. Pure jadeite and kosmochlor Specific gravity: Most specimens measured spectra (traces 1 and 3) are shown for by the hydrostatic method had SGs of 3.30- comparison, and the similarity of the hte 3.31, floating in di-iodomethane, but there is long sein and jadeite traces is evident. some variation due to the coarse textures and variable contents of fine cracks. If the jadeite The petrology contains any of the glistening hornblende In thin section (Figures 7 and 8), the hte like minerals, SGs are lower. long sein can be seen to consist of 80-98% Refractive index: the average RI is 1.66 by jadeite. Some grains are colourless, others are the distant vision method. pale green with distinct pleochroism from /. Gemm., 2001, 27, 6, 321-327 J-001 2 I CO c 325323 1200 Raman Shift (cm*1) Figure 6: Laser Raman spectrum of pyroxene jade: J-001 jadeite jade; J-002 hte long sein; J-003 kosmochlor jade. Figure 7: Prismatic chrome-rich jadeite in hte Figure 8: Fine sub-parallel cracks are visible long sein jade displays bluish-green / light yellow crossing the c-axis of prismatic crystals ofchrome- pleochroism. Field of view 4.25 mm. Plane rich jadeite in hte long sein jadeite jade.