RUBIES and FANCY-COLOR SAPPHIRES from NEPAL by Christopher P
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Program Outline 434- Jewellery and Metalwork NUNAVUT INUIT LANGUAGES AND CULTURES Jewelry and Metalwork (and all fine arts) PROGRAM REPORT 434 Jewellery and Metalwork Start Term: No Specified End Date End Term: No Specified End Date Program Status: Approved Action Type: N/A Change Type: N/A Discontinued: No Latest Version: Yes Printed: 03/30/2015 1 Program Outline 434- Jewellery and Metalwork Program Details 434 - Jewellery and Metalwork Start Term: No Specified End Date End Term: No Specified End Date Program Details Code 434 Title Jewellery and Metalwork Start Term No Specified End Date End Term No Specified End Date Total Credits Institution Nunavut Faculty Inuit Languages and Cultures Department Jewelry and Metalwork (and all fine arts) General Information Eligible for RPL No Description The Program in Jewellery and Metalwork will enable students to develop their knowledge and skills of jewellery and metalwork production in a professional studio atmosphere. To this end the program stresses high standards of craftship and creativity, all the time encouraging and exposing students to a wide range of materials, techniques and concepts. This program is designed to allow the individual student to specialize in an area of study of particular interest. There is an emphasis on creative thinking and problem-solving throughout the program.The first year of the program provides an environment for the students to acquire the necessary skills that will enable them to translate their ideas into two and three dimensional jewellery and metalwork. This first year includes courses in: Drawing and Design, Inuit Art and Jewellery History, Lapidary and also Business and Communications. -
Preliminary Investigation of Purple Garnet from a New Deposit in Mozambique
GIT GEMSTONE UPDATE Preliminary Investigation of Purple Garnet from a New Deposit in Mozambique By GIT-Gem testing laboratory 11 May 2016 Introduction In March 2016, a group of Thai gem dealer led by Mr. Pichit Nilprapaporn paid a visit to the GIT and informed us about a new garnet deposit in Mozambique, that was discovered near the western border with Zimbabwe. They also displayed a large parcel of rough and a few cut stones claimed to be the material found in this new deposit (Figure 1). According to the stone’s owner, these garnet specimens were unearthed from an unconsolidated sediment layer, just a few meters below ground surface. This brief report is our preliminary investigation on the interesting vivid purple garnet from the new deposit in Mozambique. Figure 1: Mr. Pichit Nilprapaporn (center), the stone’s owner, showing a large parcel of purple gar- net roughs claimed to be from a new deposit in Mozambique to the GIT director (left). The Gem and Jewelry Institute of Thailand (Public Organization) 140, 140/1-3, 140/5 ITF-Tower Building. 1st - 4th and 6th Floor,Silom Road, Suriyawong, Bangrak, Bangkok 10500 Thailand Tel: +66 2634 4999 Fax: +66 2634 4970; Web: http://www.git.or.th; E-mail: [email protected] 11 May, 2016 Preliminary Investigation of Purple Garnet from a New Deposit in Mozambique 2 Samples and Testing Procedure The stone’s owners donated some specimens (one 6.10 ct oval-facetted stone and 13 rough samples weighing from 3.83 to 9.43 cts) to the GIT Gem Testing Laboratory for studying. -
HIGHLIGHTS and BREAKTHROUGHS Sapphire, A
1 HIGHLIGHTS AND BREAKTHROUGHS 2 Sapphire, a not so simple gemstone 3 F. LIN SUTHERLAND1* 4 1Geoscience, Australian Museum, 1 William Street, Sydney, NSW 2010, Australia. 5 *E-mail: [email protected] 6 Abstract: Sapphire is a gemstone of considerable reach and is much researched. It still delivers scientific surprises, as exemplified by a 7 recent paper in American Mineralogist that re-interprets the origin of needle-like rutile inclusions that form “silk” in sapphires. 8 Understanding of variations in sapphire genesis continues to expand. Keywords: Sapphire, inclusions, trace elements, genesis 9 Sapphire as a gem variety of corundum has wide use in the gem trade as one of the more historically valuable colored gem stones 10 (CGS) and is mined from a great variety of continental gem deposits across the world. A masterly compendium on this gemstone and its 11 ramifications is recently available (Hughes 2017). As a gem, sapphire ranges through all the colors of corundum, except where 12 sufficient Cr enters its α-alumina crystal structure and causes the red color of the variety ruby. Sapphire, as a key pillar in a wide 13 economic network of gem enhancing treatments, jewelry and other manufacturing enterprises, has elicited numerous scientific and 14 gemological enquiries into its internal nature and natural genesis and subsequent treatments. A further use of sapphire as a synthetic 15 material with a great variety of purposes also has triggered a proliferation of detailed studies on its growth, properties and other element 16 substitutional effects (Dobrovinski et al. 2009). Even with this vast range of studies, this apparently simple gemstone still yields 17 controversies and breakthroughs in understanding its genetic formation. -
Distinctive Designs
Distinctive Designs Brides Ring in an Era of Self-Expression by Stacey Marcus Diamond rings have been sporting the hands of newly can elevate a traditional setting to an entirely new level. While engaged women since ancient times. In the mid 1940s, diamonds are always in vogue for engagement rings, millen- DeBeers revived the ritual with its famous “Diamonds Are nials are also opting for nontraditional stones, such as color- Forever” campaign. Today’s brides are blazing new trails by changing alexandrite, beautiful tanzanite, black opal, and even selecting nontraditional wedding rings that express their aquamarine. We are in an age when anything goes, and brides individual style. are embracing the idea of individuality and self-expression!” True Colors says Jordan Fine, CEO of JFINE. “Brides today want to be unique and they don’t mind taking Kathryn Money, vice president of strategy and merchandising chances with colors, settings, and stones. When it comes to at Brilliant Earth agrees: “Customers are seeking products that choosing an engagement ring, natural pink, blue, and even express their individuality and are increasingly drawn towards green diamonds are trending. These precious and rare dia- uniqueness. They want a ring that isn’t like everyone else’s, monds originate from only a few mines in the world, and they which we’re seeing manifested in many different ways, such 34 Spring 2018 BRIDE&GROOM as choosing a distinctive ring setting, using colored gemstones in lieu of a diamond, using a fancy (non-round) diamond, or opting for rose gold.” Money adds that 16% of respondents in a recent survey they conducted favored a colored gemstone engagement ring over a diamond. -
Examples from NYF Pegmatites of the Třebíč Pluton, Czech Republic
Journal of Geosciences, 65 (2020), 153–172 DOI: 10.3190/jgeosci.307 Original paper Beryllium minerals as monitors of geochemical evolution from magmatic to hydrothermal stage; examples from NYF pegmatites of the Třebíč Pluton, Czech Republic Adam ZACHAŘ*, Milan NOVÁK, Radek ŠKODA Department of Geological Sciences, Faculty of Sciences, Masaryk University, Kotlářská 2, Brno 611 37, Czech Republic; [email protected] * Corresponding author Mineral assemblages of primary and secondary Be-minerals were examined in intraplutonic euxenite-type NYF peg- matites of the Třebíč Pluton, Moldanubian Zone occurring between Třebíč and Vladislav south of the Třebíč fault. Primary magmatic Be-minerals crystallized mainly in massive pegmatite (paragenetic type I) including common beryl I, helvite-danalite I, and a rare phenakite I. Rare primary hydrothermal beryl II and phenakite II occur in miarolitic pockets (paragenetic type II). Secondary hydrothermal Be-minerals replaced primary precursors or filled fractures and secondary cavities, or they are associated with ,,adularia” and quartz (paragenetic type III). They include minerals of bohseite-ba- venite series, less abundant beryl III, bazzite III, helvite-danalite III, milarite-agakhanovite-(Y) III, phenakite III, and datolite-hingganite-(Y) III. Chemical composition of the individual minerals is characterized by elevated contents of Na, Cs, Mg, Fe, Sc in beryl I and II; Na, Ca, Mg, Fe, Al in bazzite III; REE in milarite-agakhanovite-(Y) III; variations in Fe/Mn in helvite-danalite and high variation of Al in bohseite-bavenite series. Replacement reactions of primary Be- -minerals are commonly complex and the sequence of crystallization of secondary Be-minerals is not defined; minerals of bohseite-bavenite series are mostly the latest. -
The World of Pink Diamonds and Identifying Them
GEMOLOGY GEMOLOGY as to what dealers can do to spot them using standard, geologists from Ashton Joint Venture found certain indicator The World of Pink Diamonds inexpensive instruments. The commercial signifcance of minerals (such as ilmenite, chromite, chrome diopside, the various types will also be touched on. and pyrope garnet) in stream-gravel concentrates which indicated the presence of diamond-bearing host rocks. and Identifying Them Impact of Auction Sales Lamproites are special ultrapotassic magnesium-rich In the late 1980s, the public perception surrounding fancy- mantle-derived volcanic rocks with low CaO, Al2O3, Na2O colored diamonds began to change when the 0.95-carat and high K2O. Leucite, glass, K-richterite, K-feldspar and Cr- By Branko Deljanin, Dr Adolf Peretti, ‘Hancock Red’ from Brazil was sold for almost $1 million per spinel are unique to lamproites and are not associated with and Matthias Alessandri carat at a Christie’s auction. This stone was studied by one kimberlites. The diamonds in lamproites are considered to be of the authors (Dr. Adolf Peretti) at that time. Since then, xenocrysts and derived from parts of the lithospheric mantle Dr. Peretti has documented the extreme impact this one that lies above the regions of lamproite genesis. Kimberlites sale has had on subsequent prices and the corresponding are also magmatic rocks but have a different composition recognition of fancy diamonds as a desirable asset class. The and could contain non-Argyle origin pink diamonds. demand for rare colors increased and the media began to play a more active role in showcasing new and previously Impact of Mining Activities unknown such stones. -
Gem Crystal Surface Features Spherical Cultured Pearls Aquamarine
Gems&Jeweller y Spring 2012 / Volume 21 / No. 1 Gem crystal Spherical Aquamarine- surface features cultured pearls coloured glass The Gemmological Association of Great Britain MARCUS MCCALLUM FGA PRECIOUS STONES, BEADS & PEARLS A wide range of precious and semi-precious stones, beads and freshwater pearls, personally selected from around the world. Unusual stones a speciality. ROOM 27-31, NEW HOUSE 67-68 HATTON GARDEN, LONDON EC1N 8JY TELEPHONE: +44(0)20 7405 2169 FACSIMILE: +44(0)20 7405 9385 email:[email protected] www.marcusmccallum.com Gems&Jewellery / Spring 2012 / Volume 21 / No. 1 Gem-A CalendarEditorial Gems&Jewellery Winds of change This year is turning in to a busy one for Gem-A. As reported in Gem-A News and Views (page Spring 40), we have a lease renewal on our Greville Street premises which will lead to a thorough refurbishment — something which those of you who know the building will agree is much needed. This will provide an excellent opportunity to reinvigorate both our onsite teaching facilities and the services we can offer members. How can we afford this you may ask, when only a very few years 12 ago the Association was in poor health financially? The fact is that over the last few years we have run a very tight ship knowing we had these costs looming. We have focused on what we are good Contents at and the things which are the core aspects of our business. This has led to the ceasing of loss- making operations, such as the laboratory, and an increase in students and thus revenue from our education, though it must be qualified that this increase is from overseas rather than the UK. -
1469 Vol 43#5 Art 03.Indd
1469 The Canadian Mineralogist Vol. 43, pp. 1469-1487 (2005) BORATE MINERALS OF THE PENOBSQUIS AND MILLSTREAM DEPOSITS, SOUTHERN NEW BRUNSWICK, CANADA JOEL D. GRICE§, ROBERT A. GAULT AND JERRY VAN VELTHUIZEN† Research Division, Canadian Museum of Nature, P.O. Box 3443, Station D, Ottawa, Ontario K1P 6P4, Canada ABSTRACT The borate minerals found in two potash deposits, at Penobsquis and Millstream, Kings County, New Brunswick, are described in detail. These deposits are located in the Moncton Subbasin, which forms the eastern portion of the extensive Maritimes Basin. These marine evaporites consist of an early carbonate unit, followed by a sulfate, and fi nally, a salt unit. The borate assemblages occur in specifi c beds of halite and sylvite that were the last units to form in the evaporite sequence. Species identifi ed from drill-core sections include: boracite, brianroulstonite, chambersite, colemanite, congolite, danburite, hilgardite, howlite, hydroboracite, kurgantaite, penobsquisite, pringleite, ruitenbergite, strontioginorite, szaibélyite, trembathite, veatchite, volkovskite and walkerite. In addition, 41 non-borate species have been identifi ed, including magnesite, monohydrocalcite, sellaite, kieserite and fl uorite. The borate assemblages in the two deposits differ, and in each deposit, they vary stratigraphically. At Millstream, boracite is the most common borate in the sylvite + carnallite beds, with hilgardite in the lower halite strata. At Penobsquis, there is an upper unit of hilgardite + volkovskite + trembathite in halite and a lower unit of hydroboracite + volkov- skite + trembathite–congolite in halite–sylvite. At both deposits, values of the ratio of B isotopes [␦11B] range from 21.5 to 37.8‰ [21 analyses] and are consistent with a seawater source, without any need for a more exotic interpretation. -
NVMC Nov 2019 Newsletter.Pdf
The Mineral Newsletter Meeting: November 18 Time: 7:45 p.m. Long Branch Nature Center, 625 S. Carlin Springs Rd., Arlington, VA 22204 Volume 60, No. 9 November 2019 Explore our website! November Meeting Program: Making Sugarloaf Mountain (details on page 5) In this issue … Mineral of the month: Datolite ................. p. 2 November program details ........................ p. 5 Annual Holiday Party coming up! ............. p. 5 President’s collected thoughts .................. p. 5 October meeting minutes .......................... p. 7 Nominations for 2019 club officers ........... p. 8 Datolite nodule Club show volunteers needed! .................. p. 8 Quincy Mine, Michigan Bench tip: Sheet wax with adhesives ......... p. 9 Source: Brandes (2019). Photo: Paul T. Brandes. Annual show coming up—Help needed! .. p. 10 EFMLS: Wildacres—finally! ........................ p. 12 AFMS: Scam targets mineral clubs ............ p. 13 Safety: Be prepared ................................... p. 13 Deadline for Submissions Field trip opportunity ................................. p. 14 November 20 Manassas quarry geology, pt. 2 ................. p. 15 Please make your submission by the 20th of the month! Upcoming events ....................................... p. 20 Submissions received later might go into a later newsletter. 28th Annual Show flyer ............................. p. 21 Mineral of the Month Datolite by Sue Marcus Datolite, our mineral this month, is not a zeolite, alt- hough it often occurs with minerals of the Zeolite Group. It can form lustrous crystals or attractive masses that take a nice polish. And, for collectors like Northern Virginia Mineral Club me, it is attainable! members, Etymology Please join our guest speaker, Joe Marx, for dinner at Datolite was named in 1806 by Jens Esmark, a Danish- the Olive Garden on November 18 at 6 p.m. -
On Crystalhzed Danburite from Russell, St. Law Rence County, New York,- by GEO
111 ART. XV. - On Crystalhzed Danburite from Russell, St. Law rence County, New York,- by GEO. J. BRUSH and EDWARD S. DANA. H£siorical Note.--In December last (1879) we received a box of minerals from Mr. C. D. Nims, the well-known mineral col lector of Northern New York, containing several specimens labelled "unknown." Among these were a few prismatic white weathered crystals that had been considered to be feld spar, to which our attention was specially called by Mr. Nims. On a pyrognostic examination this substance proved to be an anhydrous boro-silicate, corresponding in physical characters with the rare species danburite. Mr. Nims at that time gener ously placed at our disposal all of the small amount of this material he had in his possession, for scientific examination_ These specimens we investigated as thoroughly as they allowed both chemically and crystallographically, and the conclusions reached were identical with those described in this paper. Upon learning further from Mr. Nims that there w·as a proba bility of his being able to obtain, in the following spring, more abundant material and of better quality, we deferred publica tion. Our expectations and those of Mr. Nims have been fully 112 Brush and Dana-Danburitefrom Russell, N. Y realized, and the material which he has forwarded to us, as the result of his recent active explorations, is all that could be de sired both as to quantity and quality. We take pleasure in acknowledging here our indebtedness to him for his prompt ness and liberality. Method of occurrence.-The mineral occurs both crystallized and massive, imbedded in what Mr. -
FLUORINE in HAMBERGITE] Groncb Swrtzrt, Rov S. Clenxo, Jn., T/. S. L
THE AMERICAN MINERALOGIST, VOL. .50, JANUARY-FEBRUARY, 1965 FLUORINE IN HAMBERGITE] GroncB Swrtzrt, Rov S. Clenxo, Jn., t/. S. l{otional Museum, W ashington,D. C.; Jonu SrNxeNxes, Scripps Institute of Oceanography,Lin'iz:ersity oJ CaliJornio, La Jolla; aNt HBT.BNW. WonrurNc, [/. S' Geologi,cal S wrttey, Il/ ashi,ngton,D. C. Aesrnecr A chemical analysis of hambergite [Be:(OH, F)(BOt] from the Little Three mine, near Ramona, San Diego County, California, disciosed that the minerai from this Iocality contains 6.0 per cent fluorine. Hambergite from a secondCalifornia localitl., the Himalaya mine near Mesa Grande, contains 0.2 per cent fluorine Fluorine $'as not reported in analyses in the ]iterature of hambergite from Madagascar, Norway, and Kashmir' New analyses of Madagascar and Norway hambergite gave 1 0 and 0 15 per cent fluorine, re- spectively. No material from Kashmir u'as available for study. New data on hambergite from Anjanabanoana, Madagascar, and the Little Three mine, California, follow: Madagascar-BeO 53.6, 8z0136.0,HrO 8.8, F 1.0, iessO-F 0.4, sum 99.0 per cent; orthorhombic,a:9.76+O.Ol, b:12.23+O-01' c:4.43*0.01 A. Cali- fornia-BeO 529,82Ot36.6, HrO 6.7,F 6 0, O=F 2.5, sum 99'4per centlorthorhombic, a:9 78+0.01,b:12.40+0.01 , c:447+0.014; density2.372 (obs) gms/cm3;a:1.543, B:1.580, "r:1 617+0.001,2Y:90o. Crystals from the Little Three mine shou'two new forms, 13401and {341}. -
Mineralogy and Geochemical Evolution of the Little Three
American Mineralogist, Volume 71, pages 406427, 1986 Mineralogy and geochemicalevolution of the Little Three pegmatite-aplite layered intrusive, Ramona,California L. A. SrnnN,t G. E. BnowN, Jn., D. K. Brno, R. H. J*rNs2 Department of Geology, Stanford University, Stanford, California 94305 E. E. Foono Branch of Central Mineral Resources,U.S. Geological Survey, Denver, Colorado 80225 J. E. Snrcr,nv ResearchDepartment, Gemological Institute of America, 1660 Stewart Street,Santa Monica, California 90404 L. B. Sp.c,uLDrNG" JR. P.O. Box 807, Ramona,California 92065 AssrRAcr Severallayered pegmatite-aplite intrusives exposedat the Little Three mine, Ramona, California, U.S.A., display closelyassociated fine-grained to giant-texturedmineral assem- blageswhich are believed to have co-evolved from a hydrous aluminosilicate residual melt with an exsolved supercriticalvapor phase.The asymmetrically zoned intrusive known as the Little Three main dike consists of a basal sodic aplite with overlying quartz-albite- perthite pegmatite and quartz-perthite graphic pegmatite. Muscovite, spessartine,and schorl are subordinate but stable phasesdistributed through both the aplitic footwall and peg- matitic hanging wall. Although the bulk composition of the intrusive lies near the haplo- granite minimum, centrally located pockets concentratethe rarer alkalis (Li, Rb, Cs) and metals (Mn, Nb, Ta, Bi, Ti) of the system, and commonly host a giant-textured suite of minerals including quartz, alkali feldspars, muscovite or F-rich lepidolite, moderately F-rich topaz, and Mn-rich elbaite. Less commonly, pockets contain apatite, microlite- uranmicrolite, and stibio-bismuto-columbite-tantalite.Several ofthe largerand more richly mineralized pockets of the intrusive, which yield particularly high concentrationsof F, B, and Li within the pocket-mineral assemblages,display a marked internal mineral segre- gation and major alkali partitioning which is curiously inconsistent with the overall alkali partitioning of the system.