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GemmologyThe Journal of Volume 35 / No. 8 / 2017 The Gemmological Association of Great Britain Contents GemmologyThe Journal of Volume 35 / No. 8 / 2017 COLUMNS p. 702 687 What’s New D-Scope+ microscope|EXA spectrometer|GIA iD100 gem testing device|Melee Inspector| Presidium Synthetic Diamond p. 713 Screener II|SYNTHdetect mounted diamond screen- ing device|CIBJO Congress reports|Canadian diamond anniversary|GRS colour terms| Jordan Wilkins photo GSA gem abstracts| Margaritologia pearl news- letter|Santa Fe Symposium proceedings|Fei cui testing in Hong Kong ARTICLES 691 Gem Notes A. Reys photo Baryte from South Dakota, USA| Feature Articles Gems from Mong Long, Myan- mar|Pyrite and other sulphides 708 Coloured Stone Mining and Trade in Brazil: from Peru|Purple spinel from A Brief History and Current Status Badakhshan, Afghanistan| By Aurélien Reys Windmill-cut topaz from Nam- ibia|Tourmaline from Masisi, DRC|Yellow tourmaline from 728 Radiocarbon Age Dating of 1,000-Year-Old Pearls Mavuco, Mozambique|Tremolite from the Cirebon Shipwreck (Java, Indonesia) from Tanzania|Tsavorite from By Michael S. Krzemnicki, Laurent E. Cartier and Irka Hajdas Ethiopia|Black star CZ sold as natural star rutile|Cameos at the Natural History Museum 738 Naming of the Koh-i-Noor and the Origin of Mughal-Cut Diamonds By Anna Malecka 752 Characterization of Mexican Amber from the Yi Kwan Tsang Collection By Vittoria L. Villani, Franca Caucia, Luigi Marinoni, Alberto Leone, Maura Brusoni, Riccardo Groppali, Federica Corana, Elena Ferrari and Cinzia Galli V. L. Villani photo p. 758 Cover Photo: 766 Conferences Brazil is the source of a va- Dallas Mineral Collecting Symposium|World of Gems Conference V| riety of coloured stones, as Gem-A Conference|World Ruby Forum described in the article by A. Reys on pp. 708–726 of this issue. Shown here are several custom-cut Brazil- 772 Gem-A Notices ian gems consisting of a 9.69 ct morganite, 12.73 ct Swiss Blue topaz, 7.99 ct 786 Learning Opportunities amethyst, 3.29 ct tourma- line, 2.40 ct aquamarine, 1.12 ct Imperial topaz and 790 New Media 4.84 ct golden beryl. Courtesy of John Dyer Gems; composite photo by Ozzie Campos. 794 Literature of Interest The Journal is published by Gem-A in collaboration with SSEF and with the support of AGL and GIT. ISSN: 1355-4565, http://dx/doi.org/10.15506/JoG.2017.35.8 i The Journal of emmology G THE GEMMOLOGICAL ASSOCIATION OF GREAT BRITAIN Editor-in-Chief Production Editor Marketing Consultant Brendan M. Laurs Mary A. Burland Ya’akov Almor [email protected] [email protected] [email protected] 21 Ely Place Executive Editor Editor Emeritus Editorial Assistants London EC1N 6TD Alan D. Hart Roger R. Harding Carol M. Stockton Sarah Salmon UK Associate Editors t: +44 (0)20 7404 3334 Ahmadjan Abduriyim, Tokyo Gem Science, Tokyo, Japan; Raquel Alonso-Perez, Harvard Univer- f: +44 (0)20 7404 8843 sity, Cambridge, Massachusetts, USA; Edward Boehm, RareSource, Chattanooga, Tennessee, USA; e: [email protected] Maggie Campbell Pedersen, Organic Gems, London; Alan T. Collins, King’s College London; John w: www.gem-a.com L. Emmett, Crystal Chemistry, Brush Prairie, Washington, USA; Emmanuel Fritsch, Uni- versity of Nantes, France; Rui Galopim de Carvalho, Portugal Gemas, Lisbon, Portugal; Lee Registered Charity No. 1109555 A. Groat, University of British Columbia, Vancouver, Canada; Thomas Hainschwang, A company limited by guarantee and GGTL Laboratories, Balzers, Liechtenstein; Henry A. Hänni, GemExpert, Basel, Switzer- registered in England No. 1945780 land; Jeff W. Harris, University of Glasgow; Alan D. Hart, Gem-A, London; Ulrich Henn, Registered office: Palladium House, German Gemmological Association, Idar-Oberstein; Jaroslav Hyršl, Prague, Czech Repub- 1–4 Argyll Street, London W1F 7LD lic; Brian Jackson, National Museums Scotland, Edinburgh; Stefanos Karampelas, Bah- rain Institute for Pearls & Gemstones (DANAT), Manama, Kingdom of Bahrain; Lore Kiefert, Gübelin Gem Lab Ltd., Lucerne, Switzerland; Hiroshi Kitawaki, Central Gem Labo- ratory, Tokyo, Japan; Michael S. Krzemnicki, Swiss Gemmological Institute SSEF, Basel; Shane F. McClure, Gemological Institute of America, Carlsbad, California; Jack M. Ogden, President Striptwist Ltd., London; Federico Pezzotta, Natural History Museum of Milan, Italy; Jeffrey Maggie Campbell Pedersen E. Post, Smithsonian Institution, Washington DC, USA; Andrew H. Rankin, Kingston Univer- sity, Surrey; Benjamin Rondeau, University of Nantes, France; George R. Rossman, Califor- Vice Presidents nia Institute of Technology, Pasadena, USA; Karl Schmetzer, Petershausen, Germany; Diet- David J. Callaghan mar Schwarz, Federated International GemLab, Bangkok, Thailand; Menahem Sevdermish, Alan T. Collins Gemewizard Ltd., Ramat Gan, Israel; Guanghai Shi, China University of Geosciences, Bei- jing; James E. Shigley, Gemological Institute of America, Carlsbad, California; Christopher Noel W. Deeks P. Smith, American Gemological Laboratories Inc., New York, New York; Evelyne Stern, Lon- E. Alan Jobbins don; Elisabeth Strack, Gemmologisches Institut Hamburg, Germany; Tay Thye Sun, Far East Andrew H. Rankin Gemological Laboratory, Singapore; Pornsawat Wathanakul, Kasetsart University, Bangkok, Thailand; Chris M. Welbourn, Reading, Berkshire; Bert Willems, Leica Microsystems, Wetz- Honorary Fellows lar, Germany; Bear Williams, Stone Group Laboratories LLC, Jefferson City, Missouri, USA; Gaetano Cavalieri J.C. (Hanco) Zwaan, National Museum of Natural History ‘Naturalis’, Leiden, The Netherlands. Andrew Cody Terrence S. Coldham Content Submission Emmanuel Fritsch The Editor-in-Chief is glad to consider original articles, news items, conference/excursion reports, announcements and calendar entries on subjects of gemmological interest for Honorary Diamond Member publication in The Journal of Gemmology. A guide to the various sections and the preparation Martin Rapaport of manuscripts is given at www.gem-a.com/index.php/news-publications/publications/ journal-of-gemmology/submissions, or contact the Production Editor. Chief Executive Officer Subscriptions Alan D. Hart Gem-A members receive The Journal as part of their membership package, full details Council of which are given at www.gem-a.com/membership. Laboratories, libraries, museums and Justine L. Carmody – Chair similar institutions may become direct subscribers to The Journal. Kathryn L. Bonanno Advertising Lesley Exley Enquiries about advertising in The Journal should be directed to the Marketing Consultant. Paul F. Greer For more information, see www.gem-a.com/index.php/news-publications/publications/ Kerry H. Gregory journal-of-gemmology/advertising. Joanna Hardy Nigel B. Israel Database Coverage Jack M. Ogden The Journal of Gemmology is covered by the following abstracting and indexing services: Philip Sadler Australian Research Council academic journal list, British Library Document Supply Christopher P. Smith Service, Chemical Abstracts (CA Plus), Copyright Clearance Center’s RightFind ap- plication, CrossRef, EBSCO (Academic Search International, Discovery Service and Branch Chairmen TOC Premier), Gale/Cengage Learning Academic OneFile, GeoRef, Index Copernicus Midlands – Georgina E. Kettle ICI Journals Master List, Mineralogical Abstracts, Cambridge Scientific Abstracts (ProQuest), North East – Mark W. Houghton Scopus and the Thomson Reuters’ Emerging Sources Citation Index (in the Web of Science). South East – Veronica Wetten Copyright and Reprint Permission South West – Richard M. Slater For full details of copyright and reprint permission contact the Editor-in-Chief. The Journal of Gemmology is published quarterly by Gem-A, The Gemmological Association of Great Britain. Any opinions expressed in The Journal are understood to be the views of the contributors and not necessarily of the publisher. Printed by DG3 (Europe) Ltd. © 2017 The Gemmological Association of Great Britain Understanding Gems ™ ISSN: 1355-4565 Cert no. TT-COC-002454 ii The Journal of Gemmology, 35(8), 2017 What’s New INSTRUMENTATION D-Scope+ Microscope corundum, alexandrite, tanzanite, zircon, Imperial Introduced in September 2017, the D-Scope+ mi- topaz and emerald (and its most common fillers). croscope from HRD Antwerp is specially designed The unit measures 23 × 21 × 13 cm, weighs 3.3 for use with diamonds. Improvements on HRD’s kg and can be upgraded for additional applications. original D-Scope include its il- For more information, visit www.gemmoraman. lumination, ease of use, and com/Products/EXA.aspx. ergonomics. The user can Alberto Scarani and Mikko Åström choose from three colours of Magilabs, Helsinki, Finland and Rome, Italy darkfield lighting: yellowish, white daylight, and strong white light. The controls to GIA iD100 Gem Testing Device manipulate a stone have In April 2017, the Gemological Institute of America been redesigned to improve announced a new spectrosco- comfort, and the manipula- py-based desktop instrument tion table can be moved up and down to achieve for the screening of natural proper focus. For additional information, visit www. diamonds from simulants and hrdantwerp.com/en/product/new-d-scope. CMS synthetic (HPHT and CVD) or treated diamonds. Stones 0.9 mm in diameter (approximately EXA Spectrometer 0.005 ct) or greater, either loose In November 2017, Magilabs released the EXA, a or mounted, can be tested by pointing the probe standalone spectrometer unit able to quickly identi- at the sample. Within two seconds, the device dis- fy natural diamonds and other gems by their fluores-
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    Optical Engineering 46͑9͒, 093604 ͑September 2007͒ Evaluation of brilliance, fire, and scintillation in round brilliant gemstones Jose Sasian, FELLOW SPIE Abstract. We discuss several illumination effects in gemstones and University of Arizona present maps to evaluate them. The matrices and tilt views of these College of Optical Sciences maps permit one to find the stones that perform best in terms of illumi- 1630 East University Boulevard nation properties. By using the concepts of the main cutter’s line, and the Tucson, Arizona 85721 anti-cutter’s line, the problem of finding the best stones is reduced by E-mail: [email protected] one dimension in the cutter’s space. For the first time it is clearly shown why the Tolkowsky cut, and other cuts adjacent to it along the main cutter’s line, is one of the best round brilliant cuts. The maps we intro- Jason Quick duce are a valuable educational tool, provide a basis for gemstone grad- Jacob Sheffield ing, and are useful in the jewelry industry to assess gemstone American Gem Society Laboratories performance. © 2007 Society of Photo-Optical Instrumentation Engineers. 8917 West Sahara Avenue ͓DOI: 10.1117/1.2769018͔ Las Vegas, Nevada 89117 Subject terms: gemstone evaluation; gemstone grading; gemstone brilliance; gemstone fire; gemstone scintillation; gemstone cuts; round brilliant; gemstones; diamond cuts; diamonds. James Caudill American Gem Society Advanced Instruments Paper 060668R received Aug. 28, 2006; revised manuscript received Feb. 16, 8881 West Sahara Avenue 2007; accepted for publication Apr. 10, 2007; published online Oct. 1, 2007. Las Vegas, Nevada 89117 Peter Yantzer American Gem Society Laboratories 8917 West Sahara Avenue Las Vegas, Nevada 89117 1 Introduction are refracted out of the stone.
  • Maryland Historical Magazine, 1980, Volume 75, Issue No. 4

    Maryland Historical Magazine, 1980, Volume 75, Issue No. 4

    Maryland •listorical Magazine ublished Quarterly by The Museum and Library of Maryland History The Maryland Historical Society Winter 1980 THE MARYLAND HISTORICAL SOCIETY OFFICERS J. Fife Symington, Jr., Chairman* Robert G. Merrick, Sr., Honorary Chairman* Leonard C. Crewe, Jr., Vice Chairman* Frank H. Weller, Jr., President* J. Dorsey Brown, III, Vice President* Stuart S. Janney, III, Secretary* Mrs. Charles W. Cole, Jr., Vice President* John G. Evans, Treasurer* E. Phillips Hathaway, Vice President* J. Frederick Motz, Counsel* William C. Whitridge, Vice President* Samuel Hopkins, Past President* 'The officers listed above constitute the Society's Executive Committee. BOARD OF TRUSTEES H. Furlong Baldwin Richard R. Kline Frederick Co. Mrs. Emory J. Barber St. Mary's Co. Mrs. Frederick W. Lafferty Gary Black, Jr. John S. Lalley James R. Herbert Boone {Honorary) Charles D. Lyon Washington Co. Thomas W. Burdette Calvert C. McCabe, Jr. Philip Carroll Howard Co. Robert G. Merrick, Jr. Mrs. James Frederick Colwill Michael Middleton Charles Co. Owen Daly, II J. Jefferson Miller, II Donald L. DeVries W. Griffin Morrel Emory Dobson Caroline Co. Richard P. Moran Montgomery Co. Deborah B. English Thomas S. Nichols Charles O. Fisher Carroll Co. Addison V. Pinkney Mrs. Jacob France {Honorary) J. Hurst Purnell, Jr. Kent Co. Louis L. Goldstein Culvert Co. George M. Radcliffe Anne L. Gormer Allegany Co. Adrian P. Reed Queen Anne's Co. Kingdon Gould, Jr. Howard Co. Richard C. Riggs, Jr. William Grant Garrett Co. David Rogers Wicomico Co. Benjamin H. Griswold, III Terry M. Rubenstein R. Patrick Hayman Somerset Co. John D. Schapiro Louis G. Hecht Jacques T.