 | | Journal (article/letter/editorial) | | unusual sapphire-zircon-magnetite xenolith from the Chanthaburi Gem Province, Thailand ROBERTR. COENRAADS...Mineral Resources, Rama 6 Road, Bangkok 10400, Thailand AND F. [.IN SUTHERLAND Division of Earth and...sapphire, zircon and magnetite-bearing xenolith from Khao Wua, near Chanthaburi in Thailand, conclusively...for the sapphire, zircon and magnetite found in alluvial deposits in the Chanthaburi gem fields. The original...immiscible liquid. Uranium-lead isotope dating of zircon in the xenolith gives an age of 1 - 2 (_+ <1) million |  | | Journal (issue) | | Franks, B.Sc., Ph.D., F.G.A. South Yorkshire & District Branch: J. L Platts, F.G.A. Examiners: E. A. Jobbins...Dt.Gemmol.Ges., 23, 3, 178-9. Webster, R. (1975): GemsâTheir Sources, Descriptions and Identification,...INTENSIVE YELLOW TSILAISITE (MANGANESE TOURMALINE) OF GEM QUALITY FROM ZAMBIA By Dr KARL SCHMETZER* and Prof...â Idar-Oberstein, West Germany ABSTRACT Transparent gem tourmalines with an intensive yellow coloration from...members of the series dravite-uvite. In both groups of gem tourmalines small amounts of iron, i.e., small percentages |  | | Journal (article/letter/editorial) | | Road, Khlong Toey Nua, Watthana, Bangkok 10110, Thailand *Corresponding author, e-mail: seriwat@hotmail...inclusions and coexisting minerals of gem corundum from the Thailand area analysed by SEM-EDS in this study...includes alkali feldspar (sanidine), nepheline, zircon, hercynite-spinel series and magnetite-hercynite...chemistry, SEM-EDS, corundum, ruby, sapphire, Thailand, origin. 1. Introduction Sutherland et al. (1998a)...contains primary mineral inclusions of feldspars, zircon, Fe-Ti oxides, Nb-Ta oxides, U-Th oxides and rare-earth |  | | Journal (issue) | | Blanche of Lancaster Black Spinel from Thailand Camera-Drone Gem Exploration Volume 37 / No. 1 / 2020...Report 2019 | Gold Demand Trends 2019 | ID of Green Gems with Portable Instruments | The Journalâs Cumulative...| Maine (USA) Mineral & Gem Museum Gem Notes Hessonite from Kunar Province, Afghanistan | Olshanskyite...26â64 of this issue describes its history and the gems it contains, which consist of blue and pink sapphires...and Gem Materials By Karl Schmetzer and H. Albert Gilg Black SpinelâA Gem Material from Bo Phloi, Thailand |  | Peucat, J.J., Ruffault, P., Fritsch, E., Bouhnik-Le Coz, M., Simonet, C., Lasnier, B. (2007) Ga/Mg ratio as a new geochemical tool to differentiate magmatic from metamorphic blue sapphires. Lithos, 98 (1) 261-274 doi:10.1016/j.lithos.2007.05.001 | Journal (article/letter/editorial) | | trace elements can act as the signature of a single gem-deposit as did oxygen isotope composition (Yui et...submicroscopic inclusions of columbo-tantalite and zircon respectively. Less common trace elements (e.g....9000 ppm) and Ti (50 to 120 ppm). In Chantaburi (Thailand), sapphires are related to 3 My old alkali basalts...of Cr. In Bo Phloi (Thailand), the alluvial deposit is located 30 km north of Kanchanaburi and appears...Laos) Blue Bluegreen 1 â Chantaburi (Thailand) 4 â Bo Phloi (Thailand) 5 â Hainan 6 â Fudjian 7 â Shandong |  | Yui, Tzen-Fu, Wu, Chao-Ming, Limtrakun, Phisit, Sricharn, Weerapan, Boonsoong, Apichet (2006) Oxygen isotope studies on placer sapphire and ruby in the Chanthaburi-Trat alkali basaltic gemfield, Thailand. Lithos, 86 (3) 197-211 doi:10.1016/j.lithos.2005.06.002 | Journal (article/letter/editorial) | | the Chanthaburi-Trat alkali basaltic gemfield, Thailand Tzen-Fu Yui a,*, Chao-Ming Wu b, Phisit Limtrakun...Science, Chiang Mai University, Chiang Mai 50200, Thailand Received 6 April 2005; accepted 8 June 2005 Available...(C-T) alkali basaltic gemfield in southeastern Thailand. Sapphires have O-isotope composition in the range...4.8x to +5.0x, demonstrating that the C-T placer gem corundums cannot be phenocrysts of these basalts...sub-continental mantle as the primary source for these placer gem corundums is tentatively proposed. The surface distribution |  | | Journal (issue) | | 7 July 2003 The Gemmological Association and Gem Testing Laboratory of Great Britain ~ ~~ . âą~..., ~ '.~ ,:~ , Gemmological Association and Gem Testing Laboratory of Great Britain 27 Greville Street...(Figure 1) were purchased by a German gem merchant in northern Thailand and were said to originate from Myanmar...Myanmar by local dealers. During further trips to Thailand, our supplier was able to obtain some similar...photo by M. Glas. © Gemmological Association and Gem Testing Laboratory of Great Britain ISSN: 1355-4565 |  | Graham, Ian, Sutherland, Lin, Zaw, Khin, Nechaev, Victor, Khanchuk, Alexander (2008) Advances in our understanding of the gem corundum deposits of the West Pacific continental margins intraplate basaltic fields. Ore Geology Reviews, 34 (1) 200-215 doi:10.1016/j.oregeorev.2008.04.006 | Journal (article/letter/editorial) | | g e o r ev Advances in our understanding of the gem corundum deposits of the West PaciïŹc continental...online 3 June 2008 Keywords: Basalt Sapphire Ruby Zircon Continental margins West PaciïŹc A B S T R A C...increased our knowledge of the basalt-derived gem sapphireârubyâzircon deposits. In this paper we focus on the... We also critically review existing data on the gem corundum deposits, in order to further reïŹne a model...syngenetic inclusions of columbite-group phases, zircon, spinel and rutile, some contain additional nepheline |  | Piilonen, Paula, Sutherland, F., DaniĆĄĂk, Martin, Poirier, Glenn, Valley, John, Rowe, Ralph (2018) Zircon Xenocrysts from Cenozoic Alkaline Basalts of the Ratanakiri Volcanic Province (Cambodia), Southeast AsiaâTrace Element Geochemistry, O-Hf Isotopic Composition, U-Pb and (U-Th)/He GeochronologyâRevelations into the Underlying Lithospheric Mantle. Minerals, 8 (12) 556 doi:10.3390/min8120556 | Journal (article/letter/editorial) | | Article Zircon Xenocrysts from Cenozoic Alkaline Basalts of the Ratanakiri Volcanic Province (Cambodia)...Southeastfrom AsiaâTrace ElementBasalts Geochemistry, Zircon Xenocrysts Cenozoic Alkaline of O-Hf Isotopic U-Pb...(U-Th)/He the Ratanakiri Volcanic Composition, Province (Cambodia), GeochronologyâRevelations intoO-Hf...Published: date Abstract: Zircon xenocrysts from alkali basalts in Ratanakiri Province, Cambodia represent...represent a unique low-Hf zircon from within a 12,000 kminlong Indo-Pacific megacryst zone. Colorless, yellow |  | | Journal (article/letter/editorial) | | feldspar, low-Ca plagioclase (albiteoligoclase) and zircon. Rare inclusions include Fe,Cusulphide (low in...terrains sparsely distributed in eastern Australia, Thailand and eastern China. The lack of understanding of...alluvial processes resulted in economic deposits of the gem-quality variety sapphire in eastern Australia, eastern...China, the Indochina region of southeastern Asia (Thailand, Vietnam and Cambodia) and northern Africa (Kenya...corundum crystals in basalts of the Hoy Volcanic Province in central Queensland, Australia. At two localities |  | | Journal (article/letter/editorial) | | AND GEOCHEMISTRY OF THE DENCHAI BASALT, NORTHERN THAILAND SANDRA M. BARR Department of Geology, Acadia University...northern Thailand is part of a large continental alkalic basaltic province extending through Thailand into...basanite. The basanite is the probable source of gem-quality zircon and sapphire mined from placer deposits associated...f about 70 km 2 south o f Denchai in northern Thailand (Fig. 1). These basalts are part o f a large Late...Late Cenozoic continental basaltic province extending through Thailand, Kampuchea, Laos, and Vietnam. Petrologic |  | | Journal (article/letter/editorial) | | 92008, SC *aaron.palke@gia.edu Montana Bureau of Mines and Geology, Montana Tech, 1300 West Park Street...from their melt inclusions 59701 MA ABSTRACT Gem corundum (sapphire) has been mined from an ultramafic...deposit in central Montana has produced exceptional gem- SC quality corundum (sapphire) for more than 100...lamprophyre-hosted sapphire deposit. However, the association of gem corundum (ruby and sapphire) with mafic, ultramafic...that the genesis of some sapphires from Kanchanaburi, Thailand is directly related to the intrusion of |  | | Journal (issue) | | cabochon-cut star sapphire samples from the brown zircon and translucent to opaque dark green North-West...have been known to produce district of the Northern Rift Valley Province, and corundum in all possible...northwards through the Sudan appeared on the Kenyan gem market of which and Ethiopia (Bridges, 1982). some...stretches from the turn off the never appeared on the gem market. main Lodwar road to the Sudan. This is a...and peneplanation of hills, namely bluish-green gems. Lower grade rough can be used Pelekesh (1794m) |  | | Conference Proceedings | | term cultured pearl. Experts from various European gem testing laboratories were invited to attend a series...per country; this member being the Director of a Gem Testing Laboratory, or a gemmologist of the calibre...Stellenboch (1991), Paris, France (1993); Bangkok, Thailand (1995); Idar Oberstein, Germany (1997); Goa, India...Spain, Sri Lanka, Switzerland, Sweden, Tanzania, Thailand, U.S.A., Vietnam and Zimbabwe. During the 20th...14:40 Alessandra Costanzo , Martin Feely: Review gem-materials from Connemara, Western Ireland. 14:40 |  | | Journal (issue) | | Association and Gem Testing Laboratory of Great Britain The Gemmological Association and Gem Testing Laboratory...3334 l Fax: +44 (0)20 7404 8843 e-mail: information@gem-a.info l Website: www.gem-a.info President: E A Jobbins...very likely also be © Gemmological Association and Gem Testing Laboratory of Great Britain ISSN: 1355-4565...for alexandrite effect. Alexandrite effect (AE) Gem minerals changing colour between daylight and incandescent...first observed in a mineral found in the emerald mines at Tokowaia in the Urals (Wörth, 1842; Kokscharow |  | | Journal (issue) | | JOURNAL OF THE GEMOLOGICAL INSTITUTE OF AMERICA Gem Art of the Taj Mahal and the Mughal Era Characteristics...in Corundum from Bo Welu, Thailand Fall 2019 VOLUME 55, No. 3 EDITORIAL 293 Gem Art of the Taj Mahal...Chris L. Rogers, and Robert Weldon A look at the gem ornamentation of this landmark, as well as the jewels...in Ruby and Sapphire from the Bo Welu Gem Deposit in Chanthaburi, Thailand Supparat Promwongnan and Chakkaphan...and Color of Cultured Half-Pearls from Phuket, Thailand Kannika Kanjanachatree, Napapit Limsathapornkul |  | Baldwin, L. C., Tomaschek, F., Ballhaus, C., Gerdes, A., Fonseca, R. O. C., Wirth, R., Geisler, T., Nagel, T. (2017) Petrogenesis of alkaline basalt-hosted sapphire megacrysts. Petrological and geochemical investigations of in situ sapphire occurrences from the Siebengebirge Volcanic Field, Germany. Contributions to Mineralogy and Petrology, 172 (6) doi:10.1007/s00410-017-1362-0 | Journal (article/letter/editorial) | | Carbonatite Introduction Sapphire and ruby are gem varieties of corundum (α-Al2O3) and belong to the...gemstones, along with diamond and emerald. Deposits of gem-quality corundum are well distributed around the...g., Hughes 1997). A review of the literature on gem corundum shows that corundum occurs in various geological...volcanism as these are among the worldâs largest gem corundum suppliers (e.g., Guo et al. 1996; Limtrakun...et al. 2015), while numerous corundum, including gem crystals, were recorded in extensive flows south |  | | Journal (article/letter/editorial) | | Accepted 3 May 2017 Introduction Sapphire and ruby are gem varieties of corundum (αAl2O3): rubies are red, and...plate tectonic processes (Stern et al. 2013). These gems are concentrated in SE Asia (Yui et al. 2006; Khamloet...sapphires, compared with magmatic and metamorphic zircon ÎŽ18O. Data for rubies and sapphires are from Kerrich...in Figure 1 a comparison with a compilation of zircon ÎŽ18O. See Supplemental data for the full compiled...metamorphic zircon (Figure 1), although Groups 1B and 2B have overall greater ÎŽ18O than metamorphic zircon. Groups |  | | Journal (issue) | | and G u o Jingfeng REGULAR FEATURES Gem Trade Lab Notes Gem News Book Reviews Gemological Abstracts...Pelt-Photographers, Los Angeles, CA. Typesetting for Gems & Gemology is by Scientific Composition, Los Angeles...Japanese translation of Gems o) Gemologx contact the Association of Japan Gem Trust, Okachimachi Cy Bldg...Taito-ku, Tokyo 110, Japan. MANUSCRIPT SUBMISSIONS Gems eJ Gemology welcomes the submission of articles...editor for a copy. Letters on articles published in Gems d Geniology and other relevant matters are also |  | | Journal (article/letter/editorial) | | collected LAâICPâMS UâPb and traceelement data from zircon megacrysts at Weldborough, Tasmania, which is also...gemstone belt, subduction zone, zircon. Introduction SAPPHIRES and rubies are gem varieties of corundum (Al2O3)...2017 The Mineralogical Society accompanying gem-quality zircon (e.g. Graham et al., 2008; Giuliani et al...between intraplate Cenozoic basalts (black areas) and gem corundum deposits (unfilled hexagons). Taken and...for volcanic provinces from Raymond et al. (2012). Gem deposits compiled from Sutherland and Abduriyim (2009) |  | Giuliani, Gaston, Groat, Lee, Fallick, Anthony, Pignatelli, Isabella, Pardieu, Vincent (2020) Ruby Deposits: A Review and Geological Classification. Minerals, 10 (7) 597 doi:10.3390/min10070597 | Journal (article/letter/editorial) | | uncommon on Earth but the gem varieties of ruby and sapphire are relatively rare. Gem corundum deposits are...specifically Type IA where xenocrysts or xenoliths of gem ruby of metamorphic (sometimes magmatic) origin are...models; exploration 1. Introduction Ruby is the red gem variety of the mineral corundum. The name corundum...Rubyâ for gems mined from the modern-day Tajikistan (spinel), and âBohemian rubyâ was used for gems coming...science, but also about history, art, and trade, these gems are still called by their historic ârubyâ name, |  | | Report (issue) | | GEOLOGICAL SURVEY Geology and mineral deposits of Thailand by I/ D. R. Shawe Open-File Report 84- Prepared...Prepared on behalf of the Government of Thailand and the Agency for International Development, U.S. Department..................................... GEOLOGY OF THAILAND.................................................framework of the region surrounding Thailand..... Geologic history of Thailand............................................................................... Gem minerals........................................ |  | | 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...Asian Institute of Gemological Sciences, Bangkok, Thailand Butterworth-Heinemann London Boston Singapore...Corundum/Richard W. Hughes. p. cm.-{Butterworths gem books) Bibliography: p. Includes index ISB!'i 0-7506-1006-9:...(colour swirls), etc. Major sources: Burma, Thailand, Cambodia, Sri Lanka, India, Australia, Kenya |  | | Journal (issue) | | Phillips and Anatoly S. Talantsev Opal from Shewa Province, Ethiopia Mary L. Johnson, Robert C. Kammerling...and John I. Koivula REGULAR FEATURES Gem Trade Lab Notes Gem News Thank you, Donors Book Reviews Gemological...Guidelines for Authors ABOUT THE COVER: Perhaps no gem material in modern times carries the mystique of...Communist Russia, however, demantoids-like other gems-fell out of favor. With virtually no mining for...Pelt-Photographers, Los Angeles, CA. Color separations for Gems & Gemology are by Effective Graphics, Compton, CA |  | Palke, Aaron C., Wong, Jacqueline, Verdel, Charles, Ăvila, JanaĂna N. (2018) A common origin for Thai/Cambodian rubies and blue and violet sapphires from Yogo Gulch, Montana, U.S.A.?. American Mineralogist, 103 (3) 469-479 doi:10.2138/am-2018-6164 | Journal (article/letter/editorial) | | with rubies from the Chantaburi-Trat region of Thailand and the Pailin region of Cambodia. The similarities...rubies and Yogo sapphires suggest a common origin for gem corundum from both deposits. Specifically, we advance...the lamprophyre or basalts that transported the gem corundum to the surface partially melted Al-rich...transported them to the surface. The similarities in these gem corundum deposits suggests that the partial melting...previously realized. Importantly, in both cases the gem corundum has an ostensibly âmetamorphicâ trace element |
|
