Spring 1989 Gems & Gemology
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Summer 2006 Gems & Gemology Gem News
EDITOR Brendan M. Laurs ([email protected]) CONTRIBUTING EDITORS Emmanuel Fritsch, IMN, University of Nantes, France ([email protected]) Henry A. Hänni, SSEF, Basel, Switzerland ([email protected]) Franck Notari, GIA GemTechLab, Geneva, Switzerland ([email protected]) Kenneth V. G. Scarratt, GIA Research, Bangkok, Thailand ([email protected]) COLORED STONES AND tusk fragments. The amber in figure 1 was eventually ORGANIC MATERIALS acquired by Barry Schenck of M. M. Schenck Jeweler Inc., Chattanooga, Tennessee, who recently loaned it to GIA for Alaskan amber. Few may think of Alaska as a source of examination. Mr. Schenck has counted more than 30 amber, but the Inuit people have long collected this organ- insects trapped inside the piece, as well as other organic ic gem from northern beach gravels between Harrison Bay materials, including an apparent seedpod. GIA subsequent- and Smith Bay on the Arctic Ocean. In Gemstones of ly purchased the piece (Collection no. 35840). North America (D. Van Nostrand Co., Princeton, NJ, Most of the insects were eye-visible, though others 1959), J. Sinkankas noted that locals refer to the amber as were best seen with magnification (up to 40×). Prominent auma, which translates as “live coal.” were a mosquito, spiders, beetles, gnats, ants, and possibly In 1943, an American soldier stationed in Alaska found a bee (see, e.g., figure 2). Other inclusions consisted of gas a 117.8 g chunk of amber (figure 1) while strolling along bubbles and debris that was probably associated with the the coast. Subsequent visits to the area yielded other trees from which the amber formed. -
Raman Investigations to Identify Corallium Rubrum in Iron Age Jewelry and Ornaments
minerals Article Raman Investigations to Identify Corallium rubrum in Iron Age Jewelry and Ornaments Sebastian Fürst 1,†, Katharina Müller 2,†, Liliana Gianni 2,†, Céline Paris 3,†, Ludovic Bellot-Gurlet 3,†, Christopher F.E. Pare 1,† and Ina Reiche 2,4,†,* 1 Vor- und Frühgeschichtliche Archäologie, Institut für Altertumswissenschaften, Johannes Gutenberg-Universität Mainz, Schillerstraße 11, Mainz 55116, Germany; [email protected] (S.F.); [email protected] (C.F.E.P.) 2 Sorbonne Universités, UPMC Université Paris 06, CNRS, UMR 8220, Laboratoire d‘archéologie moléculaire et structurale (LAMS), 4 Place Jussieu, 75005 Paris, France; [email protected] (K.M.); [email protected] (L.G.) 3 Sorbonne Universités, UPMC Université Paris 06, CNRS, UMR 8233, De la molécule au nano-objets: réactivité, interactions et spectroscopies (MONARIS), 4 Place Jussieu, 75005 Paris, France; [email protected] (C.P.); [email protected] (L.B.-G.) 4 Rathgen-Forschungslabor, Staatliche Museen zu Berlin-Preußischer Kulturbesitz, Schloßstraße 1 a, Berlin 14059, Germany * Correspondence: [email protected] or [email protected]; Tel.: +49-30-2664-27101 † These authors contributed equally to this work. Academic Editor: Steve Weiner Received: 31 December 2015; Accepted: 1 June 2016; Published: 15 June 2016 Abstract: During the Central European Iron Age, more specifically between 600 and 100 BC, red precious corals (Corallium rubrum) became very popular in many regions, often associated with the so-called (early) Celts. Red corals are ideally suited to investigate several key questions of Iron Age research, like trade patterns or social and economic structures. While it is fairly easy to distinguish modern C. -
Pearls and Organic Gemstones
Pearls and Organic Gemstones INTRODUCTION Pearls were probably the first discovered gems of significance. Because they need no cutting or treatment to enhance their beauty and are rare natural occurrences, they have most likely always been highly esteemed. Organic gemstones are anything created by living processes. We have looked at amber in the past, but bone, teeth (such as ivory), and shells all have some value and are used today as gemstones. Pearls in General A pearl is grown by a mollusk (a bivalve such as a clam, oyster, or mussel or snail [single shell = valve]) in response to an irritant. Bivalves (two shelled mollusks) that secrete pearls live in both fresh‐ and saltwater. The irritant in most cases is a parasite (though it could be a grain of sand or other object). The parasite, a worm or other creature, is walled off by a secretion of calcium carbonate and protein. The calcium carbonate is the same as the inorganic material that makes stalactites in caves, and the protein is called conchiolin. The combination of these two substances (calcium carbonate and protein) makes the pearl's nacre (Nacre is also called mother of pearl). The nacre is a lustrous deposit around the irritant and forms concentric layers (overlapping circles). Many concentric layers of nacre build up over a period of a few years creating a pearl. The internal pattern is much like that seen in a jawbreaker. The layers create a sheen or luster that has iridescence and is described as both pearly luster and if colors of the rainbow are present, the pearl's orient. -
Phenomenal Gemstones Possess Striking Optical Effects, Making Them Truly a Sight for Sore Eyes
THE PHENOMENAL PROPERTIES OF GEMS Phenomenal gemstones possess striking optical effects, making them truly a sight for sore eyes. Here is GIA’s guide to understanding what makes each phenomenon so uniquely brilliant. ASTERISM CROSSING BANDS OF REFLECTED LIGHT CREATE A SIX-RAYED STAR-LIKE APPEARANCE. ASTERISM OCCURS IN THE DOME OF A CABOCHON, AND CAN BE SEEN IN GEMS LIKE RUBIES AND SAPPHIRES. ADULARESCENCE THE SAME SCATTERING OF LIGHT THAT MAKES THE SKY BLUE CREATES A MILKY, BLUISH-WHITE GLOW, LIKE MOONLIGHT SHINING THROUGH A VEIL OF CLOUDS. MOONSTONE IS THE ONLY GEM THAT DISPLAYS IT. AVENTURESCENCE FOUND IN NATURAL GEMS LIKE SUNSTONE FELDSPAR AND AVENTURINE QUARTZ, IT DISPLAYS A GLITTERY EFFECT CAUSED BY LIGHT REFLECTING FROM SMALL, FLAT INCLUSIONS. CHATOYANCY OTHERWISE KNOWN AS THE “CAT’S EYE” EFFECT, BANDS OF LIGHT ARE CAUSED BY THE REFLECTION OF LIGHT FROM MANY PARALLEL, NEEDLE-LIKE INCLUSIONS INSIDE A CABOCHON. NOTABLE GEMS THAT DISPLAY CHATOYANCY INCLUDE CAT’S EYE TOURMALINE AND CAT’S EYE CHRYSOBERYL. IRIDESCENCE ALSO SEEN IN SOAP BUBBLES AND OIL SLICKS, IT’S A RAINBOW EFFECT THAT IS CREATED WHEN LIGHT IS BROKEN UP INTO DIFFERENT COLORS. LOOK FOR IT IN FIRE AGATE AND OPAL AMMONITE (KNOWN BY THE TRADE AS AMMOLITE). LABR ADORESCENCE A BROAD FLASH OF COLOR THAT APPEARS IN LABRADORITE FELDSPAR, IT’S CAUSED BY LIGHT INTERACTING WITH THIN LAYERS IN THE STONE, AND DISAPPEARS WHEN THE GEM IS MOVED. INSIDER’S TIP: THE MOST COMMON PHENOMENAL COLOR IN LABRADORITE IS BLUE. PLAY OF COLOR THE FLASHING RAINBOW-LIKE COLORS IN OPAL THAT FLASH AT YOU AS YOU TURN THE STONE OR MOVE AROUND IT. -
Cold-Water Coral Reefs
Jl_ JOINTpk MILJ0VERNDEPARTEMENTET— — natiireW M^ iA/i*/r ONEP WCMC COMMITTEE Norwegian Ministry of the Environment TTTTr Cold-water coral reefs Out of sight - no longer out of mind Andre Freiwald. Jan Helge Fossa, Anthony Grehan, Tony KosLow and J. Murray Roberts Z4^Z4 Digitized by tine Internet Arciiive in 2010 witii funding from UNEP-WCIVIC, Cambridge http://www.arcliive.org/details/coldwatercoralre04frei i!i_«ajuiti'j! ii-D) 1.-I fLir: 111 till 1 J|_ JOINT^ MILJ0VERNDEPARTEMENTET UNEP WCMC COMMITTEE Norwegta» Ministry of the Environment T» TT F Cold-water coral reefs Out of sight - no longer out of mind Andre Freiwald, Jan HeLge Fossa, Anthony Grehan, Tony Koslow and J. Murray Roberts a) UNEP WCMCH UNEP World Conservation Supporting organizations Monitoring Centre 219 Huntingdon Road Department of the Environment, Heritage and Local Cambridge CBS DDL Government United Kingdom National Parks and Wildlife Service Tel: +44 101 1223 2773U 7 Ely Place Fax; +W 101 1223 277136 Dublin 2 Email: [email protected] Ireland Website: www.unep-wcmc.org http://www.environ.ie/DOEI/DOEIhome nsf Director: Mark Collins Norwegian Ministry of the Environment Department for Nature Management The UNEP World Conservation Monitoring Centre is the PO Box 8013 biodiversity assessment and policy implementation arm of the Dep. N-0030 Oslo United Nations Environment Programme (UNEPI. the world's Norway foremost intergovernmental environmental organization. UNEP- http://wwwmilio.no WCMC aims to help decision makers recognize the value ol biodiversity to people everywhere, and to apply this knowledge to Defra all that they do. The Centre's challenge is to transform complex Department for Environment. -
Guide to the Identification of Precious and Semi-Precious Corals in Commercial Trade
'l'llA FFIC YvALE ,.._,..---...- guide to the identification of precious and semi-precious corals in commercial trade Ernest W.T. Cooper, Susan J. Torntore, Angela S.M. Leung, Tanya Shadbolt and Carolyn Dawe September 2011 © 2011 World Wildlife Fund and TRAFFIC. All rights reserved. ISBN 978-0-9693730-3-2 Reproduction and distribution for resale by any means photographic or mechanical, including photocopying, recording, taping or information storage and retrieval systems of any parts of this book, illustrations or texts is prohibited without prior written consent from World Wildlife Fund (WWF). Reproduction for CITES enforcement or educational and other non-commercial purposes by CITES Authorities and the CITES Secretariat is authorized without prior written permission, provided the source is fully acknowledged. Any reproduction, in full or in part, of this publication must credit WWF and TRAFFIC North America. The views of the authors expressed in this publication do not necessarily reflect those of the TRAFFIC network, WWF, or the International Union for Conservation of Nature (IUCN). The designation of geographical entities in this publication and the presentation of the material do not imply the expression of any opinion whatsoever on the part of WWF, TRAFFIC, or IUCN concerning the legal status of any country, territory, or area, or of its authorities, or concerning the delimitation of its frontiers or boundaries. The TRAFFIC symbol copyright and Registered Trademark ownership are held by WWF. TRAFFIC is a joint program of WWF and IUCN. Suggested citation: Cooper, E.W.T., Torntore, S.J., Leung, A.S.M, Shadbolt, T. and Dawe, C. -
Mineral Collecting Sites in North Carolina by W
.'.' .., Mineral Collecting Sites in North Carolina By W. F. Wilson and B. J. McKenzie RUTILE GUMMITE IN GARNET RUBY CORUNDUM GOLD TORBERNITE GARNET IN MICA ANATASE RUTILE AJTUNITE AND TORBERNITE THULITE AND PYRITE MONAZITE EMERALD CUPRITE SMOKY QUARTZ ZIRCON TORBERNITE ~/ UBRAR'l USE ONLV ,~O NOT REMOVE. fROM LIBRARY N. C. GEOLOGICAL SUHVEY Information Circular 24 Mineral Collecting Sites in North Carolina By W. F. Wilson and B. J. McKenzie Raleigh 1978 Second Printing 1980. Additional copies of this publication may be obtained from: North CarOlina Department of Natural Resources and Community Development Geological Survey Section P. O. Box 27687 ~ Raleigh. N. C. 27611 1823 --~- GEOLOGICAL SURVEY SECTION The Geological Survey Section shall, by law"...make such exami nation, survey, and mapping of the geology, mineralogy, and topo graphy of the state, including their industrial and economic utilization as it may consider necessary." In carrying out its duties under this law, the section promotes the wise conservation and use of mineral resources by industry, commerce, agriculture, and other governmental agencies for the general welfare of the citizens of North Carolina. The Section conducts a number of basic and applied research projects in environmental resource planning, mineral resource explora tion, mineral statistics, and systematic geologic mapping. Services constitute a major portion ofthe Sections's activities and include identi fying rock and mineral samples submitted by the citizens of the state and providing consulting services and specially prepared reports to other agencies that require geological information. The Geological Survey Section publishes results of research in a series of Bulletins, Economic Papers, Information Circulars, Educa tional Series, Geologic Maps, and Special Publications. -
The Origins of Color in Minerals Four Distinct Physical Theories
American Mineralogist, Volume 63. pages 219-229, 1978 The origins of color in minerals KURT NASSAU Bell Laboratories Murray Hill, New Jersey 07974 Abstract Four formalisms are outlined. Crystal field theory explains the color as well as the fluores- cence in transition-metal-containing minerals such as azurite and ruby. The trap concept, as part of crystal field theory, explains the varying stability of electron and hole color centers with respect to light or heat bleaching, as well as phenomena such as thermoluminescence. The molecular orbital formalism explains the color of charge transfer minerals such as blue sapphire and crocoite involving metals, as well as the nonmetal-involving colors in lazurite, graphite and organically colored minerals. Band theory explains the colors of metallic minerals; the color range black-red-orange- yellow-colorless in minerals such as galena, proustite, greenockite, diamond, as well as the impurity-caused yellow and blue colors in diamond. Lastly, there are the well-known pseudo- chromatic colors explained by physical optics involving dispersion, scattering, interference, and diffraction. Introduction The approach here used is tutorial in nature and references are given for further reading or, in some Four distinct physical theories (formalisms) are instances, for specific examples. Color illustrations of required for complete coverage in the processes by some of the principles involved have been published which intrinsic constituents, impurities, defects, and in an earlier less technical version (Nassau, 1975a). specific structures produce the visual effects we desig- Specific examples are given where the cause of the nate as color. All four are necessary in that each color is reasonably well established, although reinter- provides insights which the others do not when ap- pretations continue to appear even in materials, such plied to specific situations. -
Nomenclature of the Garnet Supergroup
American Mineralogist, Volume 98, pages 785–811, 2013 IMA REPORT Nomenclature of the garnet supergroup EDWARD S. GREW,1,* ANDREW J. LOCOCK,2 STUART J. MILLS,3,† IRINA O. GALUSKINA,4 EVGENY V. GALUSKIN,4 AND ULF HÅLENIUS5 1School of Earth and Climate Sciences, University of Maine, Orono, Maine 04469, U.S.A. 2Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, Alberta T6G 2E3, Canada 3Geosciences, Museum Victoria, GPO Box 666, Melbourne 3001, Victoria, Australia 4Faculty of Earth Sciences, Department of Geochemistry, Mineralogy and Petrography, University of Silesia, Będzińska 60, 41-200 Sosnowiec, Poland 5Swedish Museum of Natural History, Department of Mineralogy, P.O. Box 50 007, 104 05 Stockholm, Sweden ABSTRACT The garnet supergroup includes all minerals isostructural with garnet regardless of what elements occupy the four atomic sites, i.e., the supergroup includes several chemical classes. There are pres- ently 32 approved species, with an additional 5 possible species needing further study to be approved. The general formula for the garnet supergroup minerals is {X3}[Y2](Z3)ϕ12, where X, Y, and Z refer to dodecahedral, octahedral, and tetrahedral sites, respectively, and ϕ is O, OH, or F. Most garnets are cubic, space group Ia3d (no. 230), but two OH-bearing species (henritermierite and holtstamite) have tetragonal symmetry, space group, I41/acd (no. 142), and their X, Z, and ϕ sites are split into more symmetrically unique atomic positions. Total charge at the Z site and symmetry are criteria for distinguishing groups, whereas the dominant-constituent and dominant-valency rules are critical in identifying species. Twenty-nine species belong to one of five groups: the tetragonal henritermierite group and the isometric bitikleite, schorlomite, garnet, and berzeliite groups with a total charge at Z of 8 (silicate), 9 (oxide), 10 (silicate), 12 (silicate), and 15 (vanadate, arsenate), respectively. -
Mineral Minutes May 2017 A.Pdf
THE MONTHLY NEWSLETTER OF THE MINERALOGICAL SOCIETY OF THE DISTRICT OF COLUMBIA The Mineral Volume 75-05 In this Issue: May 2017 The Prez Says⁄ Page 1 i May Program – „Geology in the National Capital Region‰ Page 1 Minutes of the April Business Meeting Page 4 April 2017 Program „What's New in Smithsonian Gems Prez Page 4 Minerals‰ Says... n Geologists Uncover Three New Uranyl Minerals Page 6 Large, Exceptional Gem Diamonds Formed from Metallic Page 7 by Dave Liquid inside EarthÊs Mantle Nanney, The Earth's Crust Is Getting Thinner Than Ever Before Page 8 MSDC President u Evidence of Ancient 'Geological Brexit' Revealed Page 9 Sapphire Rush Near Ambatondrazaka, Madagascar Page 10 A Photo-Tour of Garnets...Now in Every Color! Page 11 Blue Dravite-Uvite Tourmaline from Koksha Valley, pring is finally here. It was just Page 16 t Afghanistan pretending for the first couple of Mineral of the Month - Platinum Page 18 Sweeks but by the first week in April, Minerals of Ireland Page 19 IT IS HERE. Our garden is getting really pretty as about a third of our plants are e Geologist of the Month – John Sinkankas Page 20 in bloom. Please join us on 30 April from In Memorium - George Reimherr Page 22 1-5PM for our open house where you Mineralogical Society of America EditorsÊ Picks Page 23 can see our mineral collection, wander Upcoming Geology Events Page 24 through our 2 ½ acre garden, while carrying fluids of your choice. Reach out s Useful Mineral Links Page 24 and we can send you directions. -
Volume 35 / No. 7 / 2017
GemmologyThe Journal of Volume 35 / No. 7 / 2017 The Gemmological Association of Great Britain Contents GemmologyThe Journal of Volume 35 / No. 7 / 2017 COLUMNS p. 581 569 What’s New AMS2 melee diamond tester| p. 586 MiNi photography system| Spectra diamond colorimeter| Lab Information Circular| Gemmological Society of Japan abstracts|Bead-cultured blister pearls from Pinctada maculata|Rubies from Cambo- dia and Thailand|Goldsmiths’ S. Bruce-Lockhart photo Review|Topaz and synthetic moissanite imitating rough diamonds|Santa Fe Symposium proceedings|Colour-change ARTICLES glass imitating garnet rough| Thanh Nhan Bui photo M2M diamond-origin tracking service|More historical reading Feature Articles lists 598 The Linkage Between Garnets Found in India at the 572 Gem Notes Arikamedu Archaeological Site and Their Source at Cat’s-eye aquamarine from Meru, the Garibpet Deposit Kenya|Colour-zoned beryl from By Karl Schmetzer, H. Albert Gilg, Ulrich Schüssler, Jayshree Pakistan|Coloration of green dravite from Tanzania|Enstatite Panjikar, Thomas Calligaro and Patrick Périn from Emali, Kenya|Grossular from Tanga, Tanzania|Natrolite 628 Simultaneous X-Radiography, Phase-Contrast from Portugal|Large matrix opal and Darkfield Imaging to Separate Natural from carving|Sapphires from Tigray, Cultured Pearls northern Ethiopia|Whewellite from the Czech Republic| By Michael S. Krzemnicki, Carina S. Hanser and Vincent Revol Inclusions in sunstone feldspar from Norway and topaz from Sri 640 Camels, Courts and Financing the French Blue Lanka|Quartz with a tourmaline -
His Exhibition Features More Than Two Hundred Pieces of Jewelry Created Between 1880 and Around 1930. During This Vibrant Period
his exhibition features more than two hundred pieces of jewelry created between 1880 and around 1930. During this vibrant period, jewelry makers in the world’s centers of design created audacious new styles in response to growing industrialization and the changing Trole of women in society. Their “alternative” designs—boldly artistic, exquisitely detailed, hand wrought, and inspired by nature—became known as art jewelry. Maker & Muse explores five different regions of art jewelry design and fabrication: • Arts and Crafts in Britain • Art Nouveau in France • Jugendstil and Wiener Werkstätte in Germany and Austria • Louis Comfort Tiffany in New York • American Arts and Crafts in Chicago Examples by both men and women are displayed together to highlight commonalities while illustrating each maker’s distinctive approach. In regions where few women were present in the workshop, they remained unquestionably present in the mind of the designer. For not only were these pieces intended to accent the fashionable clothing and natural beauty of the wearer, women were also often represented within the work itself. Drawn from the extensive jewelry holdings of collector Richard H. Driehaus and other prominent public and private collections, this exhibition celebrates the beauty, craftsmanship and innovation of art jewelry. WHAT’S IN A LABEL? As you walk through the exhibition Maker and Muse: Women and Early Guest Labels were written by: Twentieth Century Art Jewelry you’ll Caito Amorose notice a number of blue labels hanging Jon Anderson from the cases. We’ve supplemented Jennifer Baron our typical museum labels for this Keith Belles exhibition by adding labels written by Nisha Blackwell local makers, social historians, and Melissa Frost fashion experts.