Newsletter July 2010
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GANZ Committee Phone Hm Phone Wk President Jill Towers FGA DGA BSc 09 575 5955 09 489 9919 Gemological Association of New Zea- 412d Lake Road, Takapuna, Auckland. Email: [email protected] land Inc Vice Pres Gavin Canty FGA 09 278 6677 Secretary Kathryn Barcham FGA 09 524 9194 09 520 0991 Treasurer Donald Francey FGA 09 377 0730 027 496 6610 PO Box 20, Shortland Street, Auckland 1140. Email [email protected] Committee Ian Bond FGA 09 09 638 9039 Paul Bunker GG 09 379 5815 Liz Carroll FGA 09 630 4134 Coralie Van Camp FGA 09 520 0362 Neil Hanna Volume 11 — Issue 1 July 2010 Newsletter Editor Graeme Petersen FGA; 9 Innverness Drive, Pyes Pa, Tauranga 3112 Phone 07 543 9282 or 027 4496 960; E-mail [email protected] Would you call this a Ruby, see inside for more details !!! My first Spectra; a Flame Fusion Synthetic Ruby (editor Graeme Petersen) Volume 11 Issue 1 Page No 28 Newsletter of the Gemological Association of New Zealand Volume 11 with spectrometers of other manufactur- Editorial July 2010 Issue 1 ers. Measurements: 65 x 50 x 27 mm; weight Hi all 70 gr; spectral range 300 - 1000 nm The portable GL Gem Spectrometer sys- Once again treatments and enhancements have kept the gemmol- tem includes attachable GL Halogen 10W ogists of the world on their toes. Many sellers of gems that have Gem light holder, fiber probe (1 m labo- enhancements seem to be very reluctant to give honest and true ratory grade UV-VIS), USB cable, 12 V descriptions of the gems they have for sale, this is especially so on power adaptor, software the major auction sites PLEASE NOTE: The spectrometer re- New Zealand’s biggest auction site allows traders to describe them quires a USB port (no separate drivers in virtually any way the like and at this time do not want to take necessary, USB 2.0/HID 1.0 compliant). any action to make these traders give accurate and true descrip- The software package contains the tions GLGemSpec program (WinNT/2000/XP/ I am on a campaign to get traders selling their gems to give HON- Vista/Win 7 and LINUX/Mac OSX (tested with wine 0.9.20 and MacOS inside Virtual- EST and TRUE descriptions of their gems and I have some of the Box); also provided is a runtime package for LabView 7.1 (for developers the VIs for rip offs and dishonest descriptions in an article in this issue. Go and LabView version 7.1 and 2009 are provided). cruise the Trade Me site for gems, you will see Glass Filled Rubies The Quick Manual explains the setup and operation of the spectrometer system but being sold with the only enhancement listed as heating or synthetic provides only sample spectra for demonstration purposes. It is hoped that users of Quartz being sold as Natural, obvious Diffusion Treated Sapphires the GLGemSpec system will help to build up an expansive spectra database which being sold as heat treated. will be made available on-line. I do not have a problem with these items being sold on auction Future upgrades to the GLGemSpec program can be down-loaded free. sites or anywhere, I do have a problem with the descriptions being This spectrometer can be order direct form the CIG supplied, some traders have a disclaimer saying they don’t know or cannot afford to have their gems tested, this is totally UNACCEPT- The total cost including freight is approx NZ$2,400 depending on the exchange rate ABLE, jewellery shops, genuine gem merchants cannot do this, so NZ v Canadian $ how come auction sites allow this!!! Their excuse is that because of Here is the link specialist nature of the types of items being listed makes it very Order now on-line at GL Gem Spectrometer System difficult for their staff to confirm whether products are accurately http://www.cigem.ca/601.html described or not. Further as a vendor, they do not take an active part in the listing process and do not take possession of the goods nor do they pre-screen listings. (try listing a fridge or a car with an Editors Note: My Spectrometer has arrived and I have it up and running it incorrect description and they soon pounce on you) certainly is a wonderful addition to my instruments , easy to set up and get going. I recommend this to all of you. I will also be doing a full review As always my I deeply indebted and my heartfelt thanks to Bear of it in a future issue of our newsletter, if anyone would like more details Williams, Wolf Kuhen and others who supply me items and or allow please feel free to contact me (details on back page of newsletter) me to reproduce their work for our newsletter Graeme Petersen F.G.A. If you see or have an item of interest please let me know Cheers Graeme Petersen FGA (editor) Volume 11 Issue 1 Page No 2 27 Specifications of the GL Gem India’s Diamond Mining History Spectrometer Inside & Diamond Mining Active & Inactive Weight: 430 grams Dimensions: 102 this issue: mm x 84 mm x 59 mm Reprinted from www.Khulsey.com India’s 3 Detector:Toshiba: TCD1304AP linear Diamond array History India's Diamonds of Golconda Detector range: 200 - 1100 nm Pixels: Auction 12 3648 Pixel size: 8 mm x200 mm Rip Off’s Diamonds were discovered in India during the 4th cen- Signal-to-noise ratio:300:1 A/D reso- tury B.C., and India was one of the first countries to lution:14 bit LED’s the 18 mine the gem. India's diamonds were prized for their size and beauty for hundreds of years. "Indian" dia- Fiber optic connector: SMA 905 to way of the future monds were mined in numerous locations that included 0.22 numerical aperture single-strand optical fiber Borneo (Landak), Golconda, Hindostan, and Raolconda. Wavelength and Optical resolu- The majority of India and Borneo's diamond deposits GL Gem 24 tion: 300-1000 nm < 1 nm (with were alluvial as opposed to Kimberlite. Spec- 50 um slit) trometer India's most prized diamonds are known as the Exposure time: 2.5 ms-10 s CCD "diamonds of Golconda," and the most famous Gol- reading time: 14 ms Data trans- conda stones include the Hope Diamond, Koh-I-Noor fer speed: 200 ms / 100 ms (2 Diamond, Orlov Diamond, and Sanc Diamond. The points binding) Special Darya-i-Nur (Sea of Light) was a rare blue-diamond Power consumption: 200mA @ weighed 186 carats, which was owned by the Nadir 5V from computer interface: USB points of Shah of Persia after it was plundered from the last 2.0, HID 2.0 (USB cable included) interest: 'Great Mughal Emperor,' Aurangzeb's heirs in the 'sack of Delhi' in 1739. Operational system: Windows 98/ • New Geology Me/XP/Vista/Windows 7 and oth- Spec- ers trometer 'Golconda' diamonds found on the Indian subcontinent, Specifications of the GL Halo- now avail- were created from the enormous forces generated by gen 10W light source and able at a the 'Tethys Oceanic Crust' colliding, and being sub- gem holder very rea- ducted under the 'Asian Continental plate' (aka plate sonable tectonics). Although these massive continental plates GL Halogen 10W light holder with collided at the incredibly slow rate of 10 centimetres built-in cosine corrector, cooling Price from per year, this was enough force over 100s of millions of fan, includes 12V power adaptor the Cana- years, to create the Himalayan Mountain range, and to (12 V battery optional, under- dian Insti- cause the necessary volcanic activity to create diamon- neath spectrometer) for portable tute of diferous intrusive and extrusive igneous rock known as use with Gemmol- 'kimberlite.' laptop computer. The holder has ogy Millions of years of erosion caused by rainfall and snow- a SMA 905 coupler and is easily melt, unearthed the diamonds from their kimberlite unmounted from the spectrome- source, and washed them downstream to their final ter; it can be connected and used Volume 11 Issue 1 Page No 26 3 it is 35%, around 1000 nm it is 45% (with aver- aged efficiency for both polarizations around 55%). That is better than other units costing twice as much. Also important is a proper light source though the GLGemSpec can be used with the fiber alone; spectroscopists often develop their own setup de- pending on the material and the type of measure- ment. For gemstone analysis a tungsten halogen light source, a xenon light, various types of lasers resting place in the alluvial river gravels of the 'Golconda' region. Golconda (golkunda) was a region located between the lower reaches of and UV-LEDs are being used. The the Godavari and Krishna rivers, in the present-day state of Andhra GL Halogen 10W is a basic light Pradesh, central India (map above). Today, the exact source of the 'lost source with built-in cosine correc- mines of Golconda' are unknown, and the India's only remaining diamond tor, cooling fan, gem positioner and source is the Majhgawan pipe near Panna (see:" Mining in India Today" is mounted directly onto the spec- below). trometer; it can also be used with spectrometers of other manufactur- Diamonds are inextricably woven into the cultural fabric and mysticism of ers. Buddhism, Hinduism, and Tibetan Lamaism. The 'dorjes' is an ancient Bud- dhist talisman shaped like a pyramidal four-faceted diamond representing The GL Gem Spectrometer is a USB the sacred mountain of Mount Meru at the 'center of the universe.' 2.0/HID compliant device and does not need a soft-ware driver as many other spectrometers do; the GLGemSpec software is simple to install (only 104 KB; it would work on an old laptop running Windows 98), easy to learn and extremely fast in obtain- ing and saving spectras.