Gems&Jeweller y Winter 2011/2012 / Volume 20 / No. 4 Gem-A Conference 2011 South Sea pearls Tucson The Gemmological Association of Great Britain MARCUS MCCALLUM FGA PRECIOUS STONES, BEADS & PEARLS A wide range of precious and semi-precious stones, beads and freshwater pearls, personally selected from around the world. Unusual stones a speciality. ROOM 27-31, NEW HOUSE 67-68 HATTON GARDEN, LONDON EC1N 8JY TELEPHONE: +44(0)20 7405 2169 FACSIMILE: +44(0)20 7405 9385 email:[email protected] www.marcusmccallum.com 40816_MMcC A4 Advert.indd 1 10/01/2012 11:59 Gems&Jewellery / Winter 2011/2012 / Volume 20 / No. 4 Editorial Gems&Jewellery Sea change Winter Our New Year wish at the beginning of the Gem-A January Newsletter was that 2012 would bring improvements in the economic and political challenges that the world saw in 2011. The re-opening of diplomatic ties between the USA and Burma raises the question as to whether the US embargo on Burmese rubies and jade, and the European embargo on all Burmese gems, will soon be lifted. 11/12 Regardless of the intentions of the embargoes, they were hardly consistent (the US predictably banned Burma rubies but not Burma petroleum products), were ignored or circumvented by much Contents of the trade, and probably had little overall effect. The statistics reported by Pala International suggest that Burmese gem production was down in 2010/11 compared with previous years, but jadeite production was up very considerably as were jadeite prices, with China being the major market. 2 Talk of politics, the future and the gem trade brings us naturally to the thorny issues of disclosure and ethics. Will 2012 take us forward? The words we use to describe gems, and gems after they've suffered at the hands of our ingenious trade, have developed in a chaotic way over Conference Special many generations. Gem nomenclature, its universality and policing is now desperately in need of a rethink — an opinion that seems to be shared by the majority of correspondents when the matter was discussed recently on Gem-A’s MailTalk network. Ideally we need to start with a clean slate, 10 draw up a consistent and logical nomenclature framework, and create or recreate an organization to seriously champion it at all levels. Can it happen? In theory yes, and it would be a tremendous service to the buying public, but in practice I won’t hold my breath (see Harry Levy's article on Gems and Minerals pages 36–37). And what about ethics in the gem supply chain in 2012, in an environmental and MARCUS MCCALLUM FGA human rights sense? Trade and customers are more aware of the issues and, ignoring those simply jumping on a convenient marketing bandwagon, things are changing slowly as people start PRECIOUS STONES, BEADS & PEARLS 21 to think about the issues. Significant change will take time, far longer than many might wish, and I am not yet convinced that the rapid growth in the number of jewellery-related companies who have been certified as showing ‘evidence of responsible business practices’ by the Responsible Jewellery Council (they range from Argos to Zenith) is a true indicator of fundamental change. A wide range of precious and semi-precious stones, beads and freshwater pearls, personally selected Through the Microscope from around the world. Jack Ogden Unusual stones a speciality. Gem-A Calendar 24 Chief Executive Offcer Shows and Exhibitions 26 Cover Picture Recent Events 30 The image shows stars of grey hollandite needles (a barium-manganese oxide) encrusted with an unidentified birefringent white mineral, all Hands-on Gemmology 32 included in quartz from Ambositra, Madagascar. Magnification approx. 30×; illumination transmitted polarized light. Photo Michael Hügi. (See Around the Trade 36 Gem-A 2012 Photo Competition, page 20.) Membership 38 Published by Editor The Gemmological Association Jack Ogden of Great Britain (Gem-A) Gem-A News and Views 39 Production Editor 27 Greville Street Georgina Brown London EC1N 8TN Organics 41 Advisory Board t: +44 (0)20 7404 3334 Mary Burland, Roger Harding and f: +44 (0)20 7404 8843 Harry Levy Journal Files 44 e: [email protected] Design and Production w: www.gem-a.com Diversifed Global ROOM 27-31, NEW HOUSE Notices 46 Graphics Group (DG3) Registered charity no. 1109555 67-68 HATTON GARDEN, LONDON EC1N 8JY Any opinions expressed in Gems & Jewellery Copyright 2012 ISSN 1746-8043 are understood to be the views of the TELEPHONE: +44(0)20 7405 2169 Stone Scoop 48 contributors and not necessarily of the publishers. FACSIMILE: +44(0)20 7405 9385 Advertising For mediapack and advertising email:[email protected] rates contact [email protected]. www.marcusmccallum.com Page 1 40816_MMcC A4 Advert.indd 1 10/01/2012 11:59 Gems&Jewellery / Winter 2011/2012 / Volume 20 / No. 4 Gem-A Conference Special Kerry Gregory reports on the Gem-A Conference, held in November 2011 Conference 2011 This year saw new and exciting things for the Gem-A Brian began by explaining that optical phenomena in gemstones are a product of Conference. Held at a new venue — the opulent Hotel the interaction of energy to produce a visible Russell in Bloomsbury, London — the Conference attracted result in the stone. There are many types of optical phenomena, resulting from a number a record number of delegates, as well as generous of causes such as mechanical force, heat, sponsorship from several quarters of the trade. The success visible light or ultraviolet (UV) light, striking images of which were shown to delegates as of the event is in keeping with Gem-A’s recent strong examples. performances in 2010 and 2011, indicating that this is set Throughout his talk Brian explained the relevance of the optical effects to gem to carry on well in to the future. testing, stressing that they are not just pretty reactions, despite the fact that many The international flavour of the Conference see Gems & Jewellery, Autumn 2011, pages designers use these effects to create new was evident, with speakers and delegates 30–32). and unusual pieces of jewellery (such as from around the world populating the full jewellery designer Jayce Wong, who utilizes and very splendid room in which the main Optical phenomena the fluorescent properties of both ruby and presentations were held. Many of these diamond in her pieces). The morning programme commenced with delegates had gold stars on their name Uses of optical phenomena in gem a speaker well-known to Gem-A: Brian badges, signifying that they were 2011 testing include using UV light to separate Jackson, Research Curator of Mineralogy graduates of the Gem-A Gemmology and diamonds from many of their imitations; at the National Museums of Scotland, and Diamond Diplomas, and not sheriffs, as Dr UV light plays an important role in a Chairman of Gem-A’s sister association, Jack Ogden was quick to note. considerable amount of diamond testing, the Scottish Gemmological Association. The winning photos from the 2011 as highlighted in the talks by both Branko Brian has experience with Fourier transform Gem-A Members’ Photo Competition were Deljanin and Gary Roskin. Tenebrescence infrared spectroscopy (FTIR), and has also on display. Relaunched and rebranded (the temporary change of a material’s published works on the identification of in 2011, the competition saw a runaway colour after exposure to UV) is also useful in carbonate minerals using infrared, as well as winner, with Michael Hügi taking the prize for aiding identification of a stone, for example, writing several chapters of the most recent overall winner, as well as for both the Natural Afghan scapolite fluoresces a strong yellow edition of Webster’s Gems. and Treated categories (for full details please colour under longwave UV light (LWUV) (1). a b c 1: Images of scapolite showing (a) colourless scapolite in daylight, (b) the fluorescent yellow colour under LWUV and (c) the tenebrescent blue colour in daylight. Photos Brian Jackson. Page 2 Gems&Jewellery / Winter 2011/2012 / Volume 20 / No. 4 Gem-A Conference Special Gem-A Conference Special After removal of the LWUV the body colour some fluorite will change colour just from the exciting, shimmering gemstones. is a steel-blue. The effect when seen under heat of your hand. All in all the diverse optical phenomena shortwave UV light (SWUV) is less noticeable, Colour change is also caused by visible shown in this illuminating and well-received while a similar looking quartz will not show light, as are other optical phenomena. talk were as seemingly endless as Brian’s this effect. Delegates were shown stones that change passion and enthusiasm for such effects. Heat can also induce spectacular effects colour depending on the direction in which in gemstones, and this effect is generally light travels through them, an effect known called thermoluminescence, although Brian as pleochroism, as seen in tanzanite and The andesine issue (ever the stickler for correctness) tells us kornerupine. Delegates were also shown At the last minute Willy Bieri, gemmologist of that it should, strictly speaking, be called stones that change colour depending on the GemResearch Swisslab (GRS), kindly stepped thermo-induced phosphorescence. One of thickness of the material, for example, the into the shoes of Dr Adolf Peretti, who was the most well-known examples of this effect Usambara effect occurring in tourmaline, unable to attend the Conference due to the can be seen in chameleon diamonds, which where it changes from green to red (2). Also severe flooding in Bangkok. Mr Bieri delivered are known to glow yellow after being heated shown were examples of reflection effects Dr Peretti’s talk entitled ‘Distinguishing to temperatures as low as 120°C, creating such as asterism in diopside, garnet and natural Tibetan copper-bearing andesine colour change.