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The Wittelsbach-Graff and Hope Diamonds: Not Cut from the Same Rough
THE WITTELSBACH-GRAFF AND HOPE DIAMONDS: NOT CUT FROM THE SAME ROUGH Eloïse Gaillou, Wuyi Wang, Jeffrey E. Post, John M. King, James E. Butler, Alan T. Collins, and Thomas M. Moses Two historic blue diamonds, the Hope and the Wittelsbach-Graff, appeared together for the first time at the Smithsonian Institution in 2010. Both diamonds were apparently purchased in India in the 17th century and later belonged to European royalty. In addition to the parallels in their histo- ries, their comparable color and bright, long-lasting orange-red phosphorescence have led to speculation that these two diamonds might have come from the same piece of rough. Although the diamonds are similar spectroscopically, their dislocation patterns observed with the DiamondView differ in scale and texture, and they do not show the same internal strain features. The results indicate that the two diamonds did not originate from the same crystal, though they likely experienced similar geologic histories. he earliest records of the famous Hope and Adornment (Toison d’Or de la Parure de Couleur) in Wittelsbach-Graff diamonds (figure 1) show 1749, but was stolen in 1792 during the French T them in the possession of prominent Revolution. Twenty years later, a 45.52 ct blue dia- European royal families in the mid-17th century. mond appeared for sale in London and eventually They were undoubtedly mined in India, the world’s became part of the collection of Henry Philip Hope. only commercial source of diamonds at that time. Recent computer modeling studies have established The original ancestor of the Hope diamond was that the Hope diamond was cut from the French an approximately 115 ct stone (the Tavernier Blue) Blue, presumably to disguise its identity after the that Jean-Baptiste Tavernier sold to Louis XIV of theft (Attaway, 2005; Farges et al., 2009; Sucher et France in 1668. -
Fall 1996 Gems & Gemology Gem News
GEM Editors Mary L. Johnson and John I. Koivula Contributing Editors Dino DeGhionno, Robert C. Kammerling, Shane F, McClure, GIA GTL, Santa Monica, California Henry A. Hanni, SSEF, Basel, Switzerland Karl Schmetzer, Petershausen, Germany DIAMONDS plus other types, whereas type Da near-colorless natural Chatham synthetic "white" diamonds at JCK show. diamonds are relatively rare. Three years ago, Tom Chatham of Chatham Created Energy-dispersive X-ray fluorescence (EDXRF] spec- Gems, San Francisco, California, announced that he troscopy disclosed both iron (Fe)and germanium (Gel in would be marketing "white" synthetic diamonds from all four crystals. GIA Research had not previously detect- Russia for jewelry use. Although it took longer than he ed germanium in any diamond, natural or synthetic. originally anticipated, Mr. Chatham offered for sale a They suspect that Ge is being added to the growth envi- number of near-colorless synthetic diamond crystals at ronment of these crystals to prevent nitrogen from incor- the June 1996 JCK show in Las Vegas, Nevada. porating into the crystal structure of the synthetic dia- Mr. Chatham offered GLA Research a brief opportu- monds, as the nitrogen would color them yellow. nity to examine about 100 of these synthetic diamond Although all of these properties indicated that these crystals (which ranged from about 10 points to almost a samples were synthetics, conclusive proof was provided carat) before the show. Most were of small size and had most readily by the metallic inclusions, which were eye- too many inclusions for faceting. Research Associate visible in all four samples, and were easily identified with Sam Muhlmeister and Research Gemologist Shane Elen magnification. -
Blue Diamond Prices Are on the Rise
This copy is for your personal, non-commercial use only. To order presentation-ready copies for distribution to your colleagues, clients or customers visit http://www.djreprints.com. https://www.barrons.com/articles/blue-diamond-prices-are-on-the-rise-1518037930 Blue Diamond Prices Are on the Rise By Ariel R. Shapiro Feb. 7, 2018 4:12 p.m. ET The fancy color diamond market is on the upswing, according to a report, with blue diamonds seeing the largest gains. Blue diamonds saw a 5.9% increase in value in the fourth quarter of 2017 in a year-over-year comparison, according to data published on Feb. 1 by the Fancy Color Research Foundation (FCRF). Pink and yellow diamond prices decreased slightly in the same period, at 0.8% and 1.8%, respectively. The market overall was up 0.1%. A fancy vivid blue diamond ring (est. $14-18 million) goes on view at Sotheby's on Oct. 13, 2017 in London. ILLUSTRATION: GETTY IMAGES FOR SOTHEBY'S In November 2017, Christie’s sold a 8.67-carat fancy intense blue diamond ring in Geneva, Switzerland for $13.2 million. The reason for this disparity has less to do with demand, than it does with the rarity of the stone, says FCRF Chairman Eden Rachminov. Demand for yellow and pink diamonds is actually higher, but the amount of blue diamonds being mined is decreasing. “Almost nothing is coming out of the ground,” he says. Pink diamonds have seen the highest gains in the last 13 years with an overall appreciation of 361.9%, according to FCRF’s index, which is compiled through survey data provided by manufacturers and brokers. -
Some Uncommon Sapphire “Imitations”: Blue Co-Zirconia, Kyanite & Blue Dumortierite Dr Michael S
Some Uncommon Sapphire “Imitations”: Blue Co-zirconia, Kyanite & Blue Dumortierite Dr Michael S. Krzemnicki Swiss Gemmological Institute SSEF [email protected] 筆者滙報數個瑞士珠寶研究院(SSEF)近期收到 in the ring showed a negative RI reading 要求鑑證的藍色寶石,經檢測後確定其中包括 (above 1.79), an isotropic optical character 一些非常罕見的藍寶石模擬石:含錮氧化鋯、 (polariscope) and thus no pleochroism at all. 藍晶石及藍線石等。 Under the microscope, we saw no inclusions, however a slightly greenish reaction under Sapphires are among the most abundant gems the LWSW and there was a weaker similar we receive at the Swiss Gemmological Institute reaction under SWUV lamps. Based on these (SSEF) for testing. From time to time, however, properties and a chemical analysis by X-ray we are quite surprised by the imitations which fluorescence (EDXRF), the blue stone was we find among the goods sent in and this can readily identified as cubic zirconia (ZrO2). then be disappointing news for the clients. In Having seen this artificial product in a wide the following short note, the author presents a range of colours, the author had not previously few uncommon imitations identified recently at seen one of such a saturated and attractive the SSEF. Identification of these imitations is blue. Based on literature (Nassau 1981) the straightforward and should be no problem for analysed traces of cobalt in that stone have any experienced gemmologist. been identified as the colouring element in this specimen. The absorption spectrum of the stone The first case is that of an attractive blue (Fig. 2) – although superposed by several rare faceted stone of approximately 1.4 ct, set in a ring with diamonds (Fig. -
Compilation of Reported Sapphire Occurrences in Montana
Report of Investigation 23 Compilation of Reported Sapphire Occurrences in Montana Richard B. Berg 2015 Cover photo by Richard Berg. Sapphires (very pale green and colorless) concentrated by panning. The small red grains are garnets, commonly found with sapphires in western Montana, and the black sand is mainly magnetite. Compilation of Reported Sapphire Occurrences, RI 23 Compilation of Reported Sapphire Occurrences in Montana Richard B. Berg Montana Bureau of Mines and Geology MBMG Report of Investigation 23 2015 i Compilation of Reported Sapphire Occurrences, RI 23 TABLE OF CONTENTS Introduction ............................................................................................................................1 Descriptions of Occurrences ..................................................................................................7 Selected Bibliography of Articles on Montana Sapphires ................................................... 75 General Montana ............................................................................................................75 Yogo ................................................................................................................................ 75 Southwestern Montana Alluvial Deposits........................................................................ 76 Specifi cally Rock Creek sapphire district ........................................................................ 76 Specifi cally Dry Cottonwood Creek deposit and the Butte area .................................... -
HK Fancy Sapphire
Hong Kong, March 2011 Fancy Coloured Sapphires: The Beauty beyond "Blue" of Sapphire and "Red" of Ruby Dr. Michael S. Krzemnicki Swiss Gemmological Institute SSEF Switzerland All photos © M.S. Krzemnicki, SSEF except where indicated. The range of colours... © Swiss Gemmological Institute SSEF 1 The range of colours... © Swiss Gemmological Institute SSEF The range of colours... © Swiss Gemmological Institute SSEF 2 The range of colours... © Swiss Gemmological Institute SSEF The range of colours... © Swiss Gemmological Institute SSEF 3 The range of colours... © Swiss Gemmological Institute SSEF The range of colours... © Swiss Gemmological Institute SSEF 4 The range of colours... © Swiss Gemmological Institute SSEF The range of colours... © Swiss Gemmological Institute SSEF 5 The range of colours... © Swiss Gemmological Institute SSEF The range of colours... © Swiss Gemmological Institute SSEF 6 The range of colours... © Swiss Gemmological Institute SSEF The range of colours... © Swiss Gemmological Institute SSEF 7 The range of colours... © Swiss Gemmological Institute SSEF The range of colours... © Swiss Gemmological Institute SSEF 8 The range of colours... © Swiss Gemmological Institute SSEF The range of colours... Fancy sapphires: The colour range beyond red of rubies and blue of sapphires © Swiss Gemmological Institute SSEF 9 The range of colours... Photo: © SilkenEast Ltd, Bangkok © Swiss Gemmological Institute SSEF The range of colours... Collection: SilkenEast Ltd, Bangkok © Swiss Gemmological Institute SSEF 10 Jewellery with fancy sapphires Photos © Luc Phan, SSEF © Swiss Gemmological Institute SSEF © Swiss Gemmological PhotoInstitute © Luc SSEF Phan, SSEF 11 Corundum Chemical composition: aluminium oxide, Al2O3 Chemical pure aluminium oxide is colourless © Wikipedia In nature always with trace elements (chemical impurities), usually: - Mg, Ti, V, Cr, Fe, Ga - and occasionally rare HFS-elements such as Nb, Sn, Ta, Th Not all trace elements are affecting the colour (e.g. -
Metamorphic and Metasomatic Kyanite-Bearing Mineral
Metamorphic and Metasomatic Kyanite-Bearing Mineral Assemblages of Thassos Island (Rhodope, Greece) Alexandre Tarantola, Panagiotis Voudouris, Aurélien Eglinger, Christophe Scheffer, Kimberly Trebus, Marie Bitte, Benjamin Rondeau, Constantinos Mavrogonatos, Ian Graham, Marius Etienne, et al. To cite this version: Alexandre Tarantola, Panagiotis Voudouris, Aurélien Eglinger, Christophe Scheffer, Kimberly Tre- bus, et al.. Metamorphic and Metasomatic Kyanite-Bearing Mineral Assemblages of Thassos Island (Rhodope, Greece). Minerals, MDPI, 2019, 10.3390/min9040252. hal-02932247 HAL Id: hal-02932247 https://hal.archives-ouvertes.fr/hal-02932247 Submitted on 7 Sep 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. minerals Article Metamorphic and Metasomatic Kyanite-Bearing Mineral Assemblages of Thassos Island (Rhodope, Greece) Alexandre Tarantola 1,* , Panagiotis Voudouris 2 , Aurélien Eglinger 1, Christophe Scheffer 1,3, Kimberly Trebus 1, Marie Bitte 1, Benjamin Rondeau 4 , Constantinos Mavrogonatos 2 , Ian Graham 5, Marius Etienne 1 and Chantal Peiffert -
Scientific Communication
SCIENTIFIC COMMUNICATION NOTES ON FLUID INCLUSIONS OF VANADIFEROUS ZOISITE (TANZANITE) AND GREEN GROSSULAR IN MERELANI AREA, NORTHERN TANZANIA ELIAS MALISA; KARI KINNUNEN and TAPIO KOLJONEN Elias Malisa: University of Helsinki, Department of Geology, SF-00170 Helsinki, Finland. Kari Kinnunen and Tapio Koljonen: Geological Survey of Finland, SF-02150 Espoo, Finland. Tanzanite is a trade name for a gem-quality has been reported in Lalatema and Morogoro in vanadiferous zoisite of deep sapphire-blue colour Tanzania and in Lualenyi and Lilani in Kenya discovered in Merelani area, Tanzania in 1967. (Naeser and Saul 1974; Dolenc 1976; Pohl and This mineral was first described as a strontium Niedermayr 1978). -bearing zoisite by Bank, H. & Berdesinski, W., Crystals of tanzanite occur mainly in bou- 1967. Other minor occurrences of this mineral dinaged pegmatitic veins and hydrothermal frac- Fig. 1. Tanzanite-bearing horizon in the graphite-rich diopside gneiss. The yellow colour indicates hydrothermal alteration, which can be used in pros- pecting for tanzanite. Length of photo ca. 8 m. 54 Elias Malisa, Kari Kinnunen and Tapio Koljonen given as Ca2Al3Si30120H (Ghose & Tsang 1971). The chemical compositions of tanzanites studied are given in Table 1. Unit cell dimensions, measured by X-ray dif- fraction, are a = 16.21, b = 5.55, c = 10.03 ± 0.01 Å in agreement with Hurlbut (1969). Zoisite shows diffraction symmetry mmmPn-a, which limits the possible space groups to Pnma if centric or Pn2, if acentric (Dallace 1968). The most striking property of tanzanite is its pleochroism, which changes from trichroic to dichroic on heating; normally its pleochroism varies: X = red-violet, Y = c = deep blue, Z = a = yellow- Fig. -
VOLUME 45, NO. 80 PLEOCHRONIC MINERALS Wednesday July 28 7:00—9:00 Pm Makiki District Park Administration Building NEXT MONTH
VOLUME 45, NO. 80 JULY 2010 PLEOCHRONIC MINERALS MEETING BY DEAN SAKABE Wednesday Pleochroic minerals are miner- July 28 als that show different colors 7:00—9:00 pm depending on what direction Makiki District you are observing the crystal. Park In order to view pleochroism Administration you need an individual transpar- Building ent crystal. This effect can be very dramatic. Many minerals NEXT MONTH are technically pleochroic, but Wednesday most often the color change is August 25, 2010 so small that it can be barely detected. For those few other LAPIDARY minerals, the color change is very, very obvious. The great- Every Thursday est change is limited to three 6:30-8:30pm colors and is called trichroic(1-3). Second-floor Arts A two color change occurrence and Crafts Bldg is called dichroic (4-5). Pleo- Makiki District chroic, which means "many col- Park ors", is used to cover both of 1-3 Tanzanite with all 3 colors of the natural these color changes. Most of trichroic crystal present and strongly show- ing down different axes of view the time, the color change is MEMBERSHIP limited to shade changes such COSTS as from pale pink to dark pink. 2008 Single: $10.00 Family: $15.00 Rock and Mineral Society of Hawai‛i INC. PLEOCHRONIC MINERALS , PAGE 2 rhombic, monoclinic, and triclinic minerals that can be trichroic. This is because they have three unique axes of symmetry and therefore three unique directions that can absorb light in three different ways. The most famous dichroic mineral is Cordierite, a Magne- sium Aluminum Silicate. -
Queer Utopia in Steven Universe Mandy Elizabeth Moore University of Florida, [email protected]
Research on Diversity in Youth Literature Volume 2 | Issue 1 Article 5 June 2019 Future Visions: Queer Utopia in Steven Universe Mandy Elizabeth Moore University of Florida, [email protected] Follow this and additional works at: http://sophia.stkate.edu/rdyl Recommended Citation Moore, Mandy Elizabeth (2019) "Future Visions: Queer Utopia in Steven Universe," Research on Diversity in Youth Literature: Vol. 2 : Iss. 1 , Article 5. Available at: http://sophia.stkate.edu/rdyl/vol2/iss1/5 This Article is brought to you for free and open access by SOPHIA. It has been accepted for inclusion in Research on Diversity in Youth Literature by an authorized editor of SOPHIA. For more information, please contact [email protected]. Moore: Future Visions: Queer Utopia in Steven Universe Since it premiered on Cartoon Network in 2013, Steven Universe has garnered both praise and criticism for its portrayal of queer characters and its flexible approach to gender. Created by Rebecca Sugar, a bisexual and nonbinary artist, the show tells the story of Steven, a half-human, half-alien teenager raised by a trio of alien parental figures called the Crystal Gems. Steven’s adventures range from helping his friends at the local donut shop to defending Earth from the colonizing forces of the Gem Homeworld. Across its five seasons, this series has celebrated many queer firsts for animated children’s content. In 2018, Steven Universe aired one of the first cartoon same-sex wedding scenes (“Reunited”), and in 2019, it became the first animated show to win a Gay and Lesbian Alliance Against Defamation (GLAAD) award, taking home the prize for Outstanding Kids and Family Programming. -
Evaluation of Brilliance, Fire, and Scintillation in Round Brilliant
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. -
Quartz: a Bull's Eye on Optical Activity
Quartz: a Bull’s Eye on Optical Activity Elise A. Skalwold The Mineralogical Society of America William A. Bassett Title: Quartz: a Bull’s Eye on Optical Activity Authors: Elise Ann Skalwold & William Akers Bassett Edition: First edition Publisher: Mineralogical Society of America, Chantilly, Virginia, USA Copyright: © 2015 by the authors, artists, and photographers. Reproduced with permission. All Rights Reserved. ISBN: 978-0-939950-00-3 Photographer & Designer: Elise A. Skalwold Front cover: Natural quartz crystal 60 x 65 x 40 mm; Hot Springs, Arkansas; ex. Dr. R.W.M. Woodside collection. Back cover: Lab-grown quartz cluster, 140 mm x 90 mm (hydrothermally grown by Mila and Vladimir A. Klipov, R&D XTALS, Inc.). Below: Natural quartz crystals and basal sections. On-going collaboration with Cornell’s Professor Emeritus William A. Bassett is truly priceless to me for this and other projects in the wings, as well as for those over the past eight years of work and research together. Bill shares my enthusi- asm for exploring the fascinating aspects of the classical science of mineralogy, and as my co-author he sets the highest bar for accuracy. All students should be so lucky to have such a mentor. Elise A. Skalwold, 2015 Ithaca, New York Mineralogical Society of America Quartz: a Bull’s Eye on Optical Activity Elise A. Skalwold [email protected] William A. Bassett [email protected] Both Authors: Department of Earth & Atmospheric Sciences Snee Hall, Cornell University Ithaca, NY 14853 All photographs: Elise A. Skalwold Figure 1. The “bull’s eye” uniaxial optic figure characteristic of quartz is indicative of its optical activity.