 | | Journal (article/letter/editorial) |
| peculiar vein-dikes of the Grenville Geologic Province, Canada. Gem zircon and associated corundum occur in...sheet mica pegmatite mines of the Spruce Pine district, Mitchell and Yancey counties. Relatively productive...approximately 3-cm zircon crystal on matrix from Sri Lanka. Rob Lavinsky specimen and photo. Figure 9. A...pale tan zircon crystals from Mount Malosa, Zomba district, Malawi. Lino Caserini specimen, Jeff Scovil photo...during 2007 are the Mineral Section of the Houston Gem and Mineral Society and the Cincinnati Mineral Society |
 | | Book |
| provides a comprehensive examination of gems and gem materials including discussion of their properties...and popularity in different cultures. The Museum's gem collection, itself the stuff of legends, is described...factors important in determining the quality of each gem and spells out the possible confusions in gemstone...TO THOSE WHO HAVE HELPED CREATE THE MINERAL AND GEM COLLECTIONS. Those whose donations are featured...Tourmaline PAGE 88 18 Zircon& What1a Rridot Gem? PAGE PAGE 22 Corundum Diamond PAGE PAGE 44 |
 | | Book |
| E. Post, Geologist, Curator-in-Charge, National Gem and Mineral Collection, National Museum of Natural...at www.dk.com CONTENTS INTRODUCTION What is a Gem? 8 How Gems Form 10 Crystals 12 Classifying...Cutting Gems 28 Polishing and Engraving Gems 30 Gem Enhancement 32 Synthetic Gems 34 History and... 214 Index 218 Acknowledgments 223 HOW THE GEM PROFILES WORK main section ; profile information...viene INTRODUCTION ‘ag yet Gay x 2 WHAT IS A GEM? Gems are generally defined as precious or semiprecious |
 | | Book |
| Edelseifen um Ratnapura . . . . . . . . . . 22 Lageskizze der Edelsteinfelder in der Provinz Sabaragamuwa Ceylons...Polonnaruwa • Kandy Nuwara Eliya Adam's Peak Ratnapura • .Pelmadulla • Rakwana Malara Karte von Ceylon...altorientalisches Dichterwort die paradiesische Insel Lanka an der Siidspitze Indiens. Es hat bis heute seine...von Edelsteinen wie gerade Ceylon.Bereits in den Lanka-Sagen finden sich manche Hinweise auf Ceylons Edelsteinreichtum...ausser Gewiirzen auch Perlen und edle Steine aus Lanka, wie Ceylon im Altertum hiess, exportiert wiirden |
 | | Book |
| assemblage such as the zeolites from India, or high gem quality such as the rubies from Burma, or some significantly...notable example in this category is the Nuristan District of Afghanistan, which over the past 10 years has...has produced some of the most extraordinary gem minerals ever found. The majority of this volume is based...Saijo, Iyo Province, Ehime Prefecture, Island of Shikoku Ashio Mine, Shimotsuke Province, Tochigi Prefecture...Arakawa Mines, Ugo Province, Akita Prefecture, Honshu The Obira Mine, Bungo Province, Oita Prefecture, |
 | | Book |
| Ian Ballour) Contents INTRODUCTION GEM IDENTIFIER Main gem groups Other gemstones Natural glasses...have tried to recognize these fakes. Synthetic gem- and optical properties by which they may be identified...on the scale grains that make them the toughest gem¬ but was in turn scratched by those beneath stones...be un¬ (9) and talc (1). For use in jewellery, gem¬ even, hackly (jagged) or conchoidal (shell - stones...hardness less than 7 are therefore likely common, gem-quality material may be to become scratched with |
 | | Book (edition) |
| carats from Burma. gemstones. Tanzania. Rare Sri Lankan orange sapphire of 57.26 carats. Emerald...illustrated. The section ends with a brief account of gem cutting. The most popular gemstones are described...final section of the book is concerned with how gem minerals form, where they are found and how they...are identified, and a selected index to the main gem species, technical terms and important topics such...Geological Museum in London. The collection consists of gem minerals in both a natural state and cut as exquisite |
 | | Book |
| Dimensions in the captions refer to the entire gem or mineral; however, in some cases only a portion...A CHANGING PLANET 11 Vanadinite, San Carlos district, Chihuahua, Mexico * 8 x 4 x 2 cm Mineral Species...can be as valuable as the richly colored stones. Gem cutters bring out the inner beauty of gems by creating...trick with light. Facets allow light to enter the gem; once inside, the light bounces off its other angled...Africa and Canada « 2.00 ct and 3.06 ct leaves the gem, similar to what happens when you pass light through |
 | | Book (edition) |
| the authors 4 Iolite (cordierite) 55 Is it a gem? 5 Andalusite, Fibrolite (sillimanite) Finding...Further reading and credits 73 Tanzanite 54 Gem deposits of the world 74 Taaffeite 54 Index ...qualities of beauty, rarity and about the individual gem species. The main durability, which are determined...are described, together with identifying gems. Gem mineral formation is notes on items of particular...outreach and (GAGTL) and the British examiner for the gem testing services. Prior to this post die was European |
 | | Book |
| E YE WI TNES S HA N D B O O KS GEM STONES The visual guide to more than 130 gemstone varieties...org/details/gemstoneseyewitnOOcall EYEWITNESS HANDBOOKS GEM STONES E YE WI TNESS HANDBOOKS GEMSTONES Cally...varieties are found and fashions change. Over 130 gem species, including some exceptionally rare stones...why the species entries in this its book show the gem rough, natural state, perhaps embedded in still...they can be appreciated by anyone, from the amateur gem-spotter to the enthusiast who enjoys their beauty |
 | | Journal (issue) |
| CVD synthetic diamond | Updated CIBJO Blue Books | Gem laboratory newsletters | New JVC Essential Guides...Photomicrography using a smartphone camera 24 Gem Notes Colourless cat’s-eye apatite | Prismatic Ethiopian...Excursions 69 From the Archives 73 Conferences 78 Gem-A Notices 80 New Media 84 Literature of Interest...Brendan M. Laurs brendan.laurs@gem-a.com Mary A. Burland mary.burland@gem-a.com Executive Editor Editor...Harding Marketing Consultant Ya’akov Almor bizdev@gem-a.com Assistant Editor Michael J. O’Donoghue Associate |
 | | Journal (issue) |
| FEATURE ARTICLES 2 A New Method for Determining Gem Tourmaline Species by LA-ICP-MS Ziyin Sun, Aaron...a simplified but comprehensive classification of gem tourmaline species based on quantitative measurement...Zircon Inclusions in Sapphires from Ratnapura and Balangoda (Sri Lanka) and Implications for Geographic...sapphire • Quarterly Crystal: Orpiment in barite 118 Gem News International Tucson 2019 • Boulder opal mining...Responsibly sourced gemstones • The Chinese and Japanese gem markets • Unusual and vibrant gems • Jeff Hapeman |
 | | Journal (issue) |
| run verticall y or horizontally righ t across the gem surface. Onyx is very popu lar in pe n da n t s an...have been the name of a town in ancient Egypt. A GEM AND A ROCK I I Most alabaster is defined as the...be artificially ""tJ Right: Although the term 'gem' is most commonly associated with the precious mountings...alabaster from Volterra, near Pisa (Italy). This gem material is basically the mineral gypsum. Although...now exhausted, but the gem can still be found in small quantities in Sri Lanka, Burma and Brazil. Alexandrite's |
 | | Book (edition) |
| EDITION AREM, PH.D., FG.A. gem gemologists, 1977, jewelers, and gem collectors, dealers have relied...INTRODUCTION What / Gem? a / Scope of This Book / Is The Nature Gems of GEM SECTION 1 2 GEMSTONES...Rock Classification Gem Scarcity Intrusive Crystal 6 Growth Synthetic Gem 9 / Gemstones SOURCES...dealers are aware of the growing value of exotic gem species; the list of known taaffeites has thus grown...greater monetary reward than are the tists who gem scien- build detection equipment. Inevitably, a |
 | | Journal (issue) |
| Manager Telephone: [800! 4 2 1-7250 x 2 0 1 Editor, Gem Trade Lab Notes C. W. Frver Editor, Gemological Abstracts...Misiorowslzi Contributing Editor, John I. Koivula Editors, Gem News John I. Koivula Robcrt C. Kammerling SUBSCRIPTIONS...Robert E. Kane 47 54 Gem Trade Lab Notes Gems & Gemology Challenge 60 Gem News Book Reviews 62 ...only did the first Sumitomo gem-quality synthetic diamonds appear on the gem marlzet, but De Beers released...information revealing just how far their experiments with gem-quality synthetic diamonds had progressed; one such |
 | | Book |
| TREASURES The IN THE SMITHSONIAN Gem Collection Paul E. Desautels ;".'*" - • * « . ^- - ...: »•• * . The Gem Collection TREASURES The IN THE SMITHSONIAN Gem Collection Paul E. Desautels...Paul E Treasures in the Smithsonian: the Gems. gem collection. Smithsonian Institution. Smithsonian...One of the more important gifts to the Smithsonian gem collection in recent years is the 68-carat Victoria-Transvaal...champagne-colored gem was discovered in Africa in 1951. CONTENTS I. II. THE NATIONAL GEM COLLECTION THE |
 | | Book (edition) |
| © Tere crree! THE CLEVER GEM BUYER Sclaolalemcveliareln GAVIN LINSELL “She is more precious than...the main reason invariably is that a particular gem means something special to us: they represent a story...perceptions. Now in its second edition, The Clever Gem Buyer brings the reader not only the ‘gemmological’...in an absorbing and entertaining way, The Clever Gem Buyer’s second edition includes even more gemstone...mountain of gemstone rings’ in Thailand's Chanthaburi Province, an international centre for coloured gemstones |
 | | Book |
| kyewitness CRYSTAL & GEM Apatite Cut topazes Calcite kyewitness CRYSTAL & GEM In association with...of an Indian woman ‘bedecked with jewellery Le GEM OF A CRYSTAL © Most gemstones are natural crystals...two shadow edges, depending on | = | whether the gem is singly or doubly = | refractive, form ona scale...containing fine gemquality crystals are known as gem pockets. This gem pocket CHANGED BY FORCE As a result of...This technique is often used to sort out gem-rich river gravels in areas such as Myanmar (formerly Burma) |
 | | Journal (issue) |
| Sapphires from Sri Lanka Kcirl Scl~metzerand Olaf Medenbach REGULAR FEATURES 112 120 124 131 Gem Trade Lab...Lab Notes Gem News Gemological Abstracts Book Reviews ABOUT THE COVER: The extraordinary play-of-color...Diffraction, one of the less common causes of color in gem materials, is described in this issue in the third...extensive listing of the known origins o f color in gem materials. The opal, from the Ditto 3 Harold &> Collection...pit. Virtually all o f the diamonds recovered are gem quality, although most are relatively small, averaging |
 | | Book |
| Diamond Industries: 143,145. Acknowledgments: A & S Gem & Mineral Co., Lazare Kaplan International, Goldberg-Weiss...20 21 23 23 24 25 26 Introduction Gem History What Are Gems? Gem Criteria Origin of Gems Marketing of...Brilliancy Specific Gravity Luster and Fluorescence Gem Cutting 31 Gems and Gemstones 32 Diamond 44 Beryl...Irradiation 150 152 153 154 155 156 Gems as Investments Gem Testing Lapidary Hobby Jewelry Metals Popular Styles...is due to their unique properties. The colors of gem materials are among the richest and purest in nature |
 | | Book |
| r· Butterworths Gem Books Edited by Peter G. Read Amber Helen Fraquet Beryl John Sinkankas and Peter... Huddlestone Topaz D. B. Hoover Butterworths Gem Books Corundum Richard W. Hughes Executive Vice...Corundum/Richard W. Hughes. p. cm.-{Butterworths gem books) Bibliography: p. Includes index ISB!'i 0-7506-1006-9:... Major sources: Burma, Thailand, Cambodia, Sri Lanka, India, Australia, Kenya, Tanzania, Montana and...we have books on gem deposits, the lapidary arts, carved gems, gem treatments, gem identification, history |
 | | Journal (issue) |
| Presentations | ‘Living Room Sessions’ Webinars Gem Notes Cover photo: The aquamarine photo on the cover...from Zambia and/or Mozambique), while the largest gem weighs 58.57 ct and is from Santa Maria, Brazil....Gemmologiques de Paris | Gem-A Conference | 37th International Gemmological Conference Gem-A Notices 820 Learning...of Interest 831 838 The Journal is published by Gem-A in collaboration with SSEF. Photo by Chunyan Wang...Brendan M. Laurs brendan.laurs@ gem-a.com Ahmadjan Abduriyim Tokyo Gem Science LLC, Tokyo, Japan Executive |
 | | Book |
| Properties of crystals Gem crystals 18 19 19 20 20 21 22 32 33 3 3.1 3.2 3.3 Gem testing Hardness Gemstones...56 4 4.1 4.2 4.3 4.4 4.5 Recent developments in gem testing 59 59 60 61 64 65 Thermal conductivity...understandably and rightly, with the science of gem testing and have covered that area very well. Details...entirely new gem mineral species have been found in the last few years; tanzanite, appearing on the gem market...with no gem potential whatever. It is not likely that many entirely new mineral species with gem application |
 | | Journal (issue) |
| No. 8 / 2019 COLUMNS What’s New 679 ABCD Pro-1 Gem Testing Set | D-Imaging Device | Raman Spectroscopy...| Jewelry Journey Podcasts | Gemewizard Gem Color Academy Gem Notes Amethyst from Zimbabwe | Apatite...Fuchsite Phantom Inclusions | Tourmaline from Sri Lanka with Transient Tenebrescence? | Diving for Natural...710–725 of this issue) and therefore does not have a Sri Lankan origin as commonly described for Roman sapphires...Trapiche Ruby from Khoan Thong, Luc Yen Mining District, Northern Vietnam 726 By Isabella Pignatelli |
 | | Journal (article/letter/editorial) |
| desert seem unlikely surroundings for a thriving gem min ing industry that was carried on- before the...shores of the Red Sea for further transport to the gem-cutting and goldsmithing workshops of Egyptian, Mediterranean...known as Sri Lanka) where waterworn pebbles of aquamarine were found in the gembearing gravels and, similarly...similarly, in the gem gravels of the Mogok district of Burma. Emeralds, especially, were known to native...century. In 1912, A . Eppler, the famous German gem expert, proposed the name bixbyite for this variety |
