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Stibiotantalite Sb(Ta, Nb)O4 C 2001-2005 Mineral Data Publishing, Version 1
Stibiotantalite Sb(Ta, Nb)O4 c 2001-2005 Mineral Data Publishing, version 1 Crystal Data: Orthorhombic. Point Group: mm2. Crystals prismatic k [010], flattened k to [001], may be equant, to 12 cm; {001} and {101} striated k [010]. Twinning: About [010] with composition plane {001}; polysynthetic. Physical Properties: Cleavage: {001}, distinct; {100} indistinct. Fracture: Subconchoidal. Tenacity: Brittle. Hardness = 5.5 D(meas.) = 7.53 (synthetic SbTaO4). D(calc.) = [7.58] Strongly pyroelectric. Optical Properties: Semitransparent. Color: Dark brown to light yellowish brown; reddish yellow, reddish brown, greenish yellow; in transmitted light, pale yellow-brown to brown, may be zoned. Streak: Pale yellow to yellow-brown. Luster: Resinous to adamantine. Optical Class: Biaxial (+). Orientation: X = a; Y = b; Z = c. Dispersion: r< v,strong. α = 2.374 β = 2.404 γ = 2.457 2V(meas.) = n.d. 2V(calc.) = 75◦50 Cell Data: Space Group: Pc21n (synthetic SbTaO4). a = 4.911 b = 11.814 c = 5.535 Z=4 X-ray Powder Pattern: Synthetic SbTaO4; nearly identical to stibiotantalite. 3.121 (100), 3.506 (38), 2.950 (34), 2.687 (22), 2.692 (21), 1.735 (19), 1.888 (17) Chemistry: (1) (2) (3) Nb2O5 1.79 11.3 Ta2O5 57.29 43.3 60.25 SiO2 0.1 Sb2O3 40.64 40.3 39.75 Bi2O3 0.30 3.8 CaO 0.1 Total 100.02 98.9 100.00 (1) Greenbushes, Western Australia. (2) Mesa Grande district, California, USA; by electron microprobe, corresponding to Sb1.00(Ta0.71Nb0.30)Σ=1.01O4. (3) SbTaO4. Mineral Group: Forms a series with stibiocolumbite. -
Spring 1982 Gems & Gemology
SPRING 1982 Volume 18 Number 1 TABLE OF CONTENTS EDITORIAL 1 The Gems & Gemology Most Valuable Article Award Richard T. Lid~licoat,Ir. FEATURE 3 The Jade Enigma ARTICLES \ill M. Hobbs 20 Jade Forms from Ancient China Evelyn Tucker 32 Some Observations on the Treatment of Lavender Jadeite Iohn I. Koivula NOTES 36 Cultured 314 Blister Pearls AND NEW Robert Crowningshield TECHNIQUES 39 The Natural Formation and Occurrence of Green Quartz Xhomas R. Paradise REGULAR 43 Editorial Forum FEATURES 44 Gem Trade Lab Notes 50 Gemological Abstracts 58 Gem News ABOUT THE COVER: The jadeite necklace and earrings illustrated here give some indication of the beauty and mystery of this material. The identification of jade and some of its simulants is comprehensively examined in the article by ]ill Hobbs. The motifs that the Chinese have used for centuries to carve jade-for example, these earrings have been formed in the shape of a pi, a symbol of heaven-are reviewed in the article by Evelyn Tucker. The natural green jadeite beads are 30 inches (75 cm) long; the largest bead is 9.5 mm in diameter. The natural green jadeite earrings are 25 mm in diameter. Courtesy of the Crystalite Corporation. Photograph s?Y81 Harold and Erica Van Pelt-Photographers, Los Angeles, CA. Composition for Gems & Gemology is by Printed Page Graphics, Fullerton, CA. The color separations are by Effective Graphics, Compton, CA. Printing is by Waverly Press, Easton, MD. "1982 Gemological Institute of America. All rights reserved. ISSN 001 6-626X EDITORIAL Editor-in-Chief Managing Editor Editor, Gem Trade Lab Notes STAFF Richard T. -
Bismutotantalite-Stibiotantalite-Stibiocolumbite Assemblage from Elbaite Pegmatites at Molo Near Momeik, Northern Shan State, Myanmar
Bismutotantalite-stibiotantalite-stibiocolumbite assemblage from elbaite pegmatites at Molo near Momeik, northern Shan State, Myanmar Novák Milan, Sejkora Jiří, Škoda Radek and Budina Václav With 5 figures and 2 tables Abstract: Bismutotantalite-stibiotantalite-stibiocolumbite (BSS) aggregates occur exclusively in pockets of the elbaite subtype pegmatites cutting serpentinized peridotite at Khetchel village, Molo quarter near Momeik Township, northeast of Mogok, Shan State, Myanmar (Burma). The pegmatites exhibit simple zoning with common pockets lined with K-feldspar, “mushroom-like” pink to red elbaite, beryl (aquamarine, morganite), petalite, phenakite, quartz, saccharoidal albite, adularia, hambergite and cookeite(?). The BSS aggregates consist of prismatic crystals of bismutotantalite-stibiotantalite (Bi/(Bi+Sb) = 0.47-0.51; Ta/(Ta+Nb) = 0.64-0.67; a = 5.6017(3), b = 11.7802(3), c = 4.9497(3) Å and V = 326.63(2) Å3), up to about 5 mm in size, and their aggregates, up to 3 cm in diameter, forming ~ 95 vol.% of the overall BSS aggregate. Oval to irregular grains blebs of stibiotantalite (Bi/(Bi+Sb) = 0.04-0.08; Ta/(Ta+Nb) = 0.62-0.68), up to 100 μm in diameter, scarcely occur in bismutotantalite-stibiotantalite. Thin veinlets of stibiocolumbite (Bi/(Bi+Sb) = 0.01-0.05; Ta/(Ta+Nb) = 0.40-0.49) with brecciated textures, up to 30 μm thick, cut bismutotantalite-stibiotantalite and rarely also stibiotantalite blebs. Two distinct compositions were found in the stibiocolumbite veinlets, W-poor and rare W-rich (up to 19.34 wt.% WO3). Late stibiocolumbite overgrowths (Bi/(Bi+Sb) = 0.01-0.03; Ta/(Ta+Nb) = 0.17-0.33) on crystals of bismutotantalite-stibiotantalite reach up to 20 μm in size. -
Z Thornton Sep 14.Qxp
Fig 2. A late 19thC Scottish dirk brooch, with three Fig 5. A lava cameo bracelet, designed as a series tiered hardstone and smokey quartz panels, to the of oval-shape vari-shade cameos depicting various faceted smokey quartz terminal, with engraved profiles of gentlemen in period dress, some with detail. £200. laurel details. £190. Victorian Vintage Jewellery Fig 3. A selection of Scottish jewellery, to include a hardstone rectangular panel bracelet and twelve brooches, four brooches of thistle design, ten with and Accesories at Fellows marks to indicate silver. £180. By Zita Thornton Victorian jewellery was very well represented who were clamouring for cameos. Shell was at Fellows in May. The choice included Scottish softer and easier to carve and cameos could be agate pieces, cameos, lockets, momento and produced more quickly and cheaply. In the mid sentimental items. There was also a selection of nineteenth century a shell cameo was likely to decorative jewellery in gold or silver, set with cost around £1-£8 compared to a hardstone gems or carved from ivory, jet, jade and coral. cameo at £5-£40. Victorian cameo jewellery was Agate and other hardstone jewellery was a most often set into gold mounts with closed or favourite of the Victorians and was made in open backs. The more elaborate the setting, the Scotland using locally found stones. Bands of more expensive the cameo, then as now. Values coloured agate, carnelian or bloodstone would for a shell cameo in the Fellows sale reached be set, usually in silver, in traditional shapes £500, Fig 4, for a cameo brooch mounted in an such as an anchor or shield, or might encircle a elaborate 18ct gold surround with blue enamel cut stone such as smokey quartz. -
New Mineral Names*,†
American Mineralogist, Volume 106, pages 1186–1191, 2021 New Mineral Names*,† Dmitriy I. Belakovskiy1 and Yulia Uvarova2 1Fersman Mineralogical Museum, Russian Academy of Sciences, Leninskiy Prospekt 18 korp. 2, Moscow 119071, Russia 2CSIRO Mineral Resources, ARRC, 26 Dick Perry Avenue, Kensington, Western Australia 6151, Australia In this issue This New Mineral Names has entries for 10 new species, including huenite, laverovite, pandoraite-Ba, pandoraite- Ca, and six new species of pyrochlore supergroup: cesiokenomicrolite, hydrokenopyrochlore, hydroxyplumbo- pyrochlore, kenoplumbomicrolite, oxybismutomicrolite, and oxycalciomicrolite. Huenite* hkl)]: 6.786 (25; 100), 5.372 (25, 101), 3.810 (51; 110), 2.974 (100; 112), P. Vignola, N. Rotiroti, G.D. Gatta, A. Risplendente, F. Hatert, D. Bersani, 2.702 (41; 202), 2.497 (38; 210), 2.203 (24; 300), 1.712 (60; 312), 1.450 (37; 314). The crystal structure was solved by direct methods and refined and V. Mattioli (2019) Huenite, Cu4Mo3O12(OH)2, a new copper- molybdenum oxy-hydroxide mineral from the San Samuel Mine, to R1 = 3.4% using the synchrotron light source. Huenite is trigonal, 3 Carrera Pinto, Cachiyuyo de Llampos district, Copiapó Province, P31/c, a = 7.653(5), c = 9.411(6) Å, V = 477.4 Å , Z = 2. The structure Atacama Region, Chile. Canadian Mineralogist, 57(4), 467–474. is based on clusters of Mo3O12(OH) and Cu4O16(OH)2 units. Three edge- sharing Mo octahedra form the Mo3O12(OH) unit, and four edge-sharing Cu-octahedra form the Cu4O16(OH)2 units of a “U” shape, which are in Huenite (IMA 2015-122), ideally Cu4Mo3O12(OH)2, trigonal, is a new mineral discovered on lindgrenite specimens from the San Samuel turn share edges to form a sheet of Cu octahedra parallel to (001). -
Antique Italian Pietra Dura Brass & Alabaster Comport Dish
anticSwiss 26/09/2021 14:08:10 http://www.anticswiss.com Antique Italian Pietra Dura Brass & Alabaster Comport Dish FOR SALE ANTIQUE DEALER Period: 19° secolo - 1800 Regent Antiques London Style: Altri stili +44 2088099605 447836294074 Height:8cm Width:29cm Depth:29cm Price:700€ DETAILED DESCRIPTION: This is a superb quality antique Italian Pietra Dura mounted, gilt brass and alabaster table-centre comport dish, dating from the late 19th Century. With striking pierced Neo-Gothic chased brass mounts this splendid alabaster dish is set with six highly decorative pietra dura roundels depicting various floral decoration. It is raised on a sturdy circular brass base. It is a sumptuous piece which will make a great statement in any special room. Condition: In really excellent condition, please see photos for confirmation. Dimensions in cm: Height 8 x Width 29 x Depth 29 Dimensions in inches: Height 3.1 x Width 11.4 x Depth 11.4 Pietra dura is a term for the inlay technique of using cut and fitted, highly polished coloured stones to create images. It is considered a decorative art. Pietre dure is an Italian plural meaning "hard rocks" or hardstones; the singular pietra dura is also encountered in Italian. In Italian, but not in English, the term embraces all gem engraving and hardstone carving, which is the artistic carving of three-dimensional objects in semi-precious stone, normally from a single piece, for example in Chinese jade. The traditional convention in English has been to use the singular pietra dura just to denote multi-colored inlay work. However, in recent years there has been a trend to use pietre dure as a term for the same thing, but not for all of the techniques it covers, in Italian. -
Title Studies on the Metamictization of Radioactive Minerals Author(S
Title Studies on the Metamictization of Radioactive Minerals Author(s) Ueda, Tateo Memoirs of the College of Science, University of Kyoto. Series Citation B (1957), 24(2): 81-120 Issue Date 1957-10-15 URL http://hdl.handle.net/2433/258495 Right Type Departmental Bulletin Paper Textversion publisher Kyoto University MEMolRS oF r!{E ComEGE oF SclENcE, UNIvERslTy OF KyoTo, SERIEs B, Vol. XXIV, No. 2 Geology and Minera!ogy, Article 1, 1957 Studies oR the Metamictization of Radioactive Minerals By [rateo UEDA Geological and Mineralogical Institute, University of Kyoto (Received June 29, 1957) Abstract Radioactive minerals are melted, portion by portien, by the irradiation arising from dis- integration of the radioactive elements contained in these minera}s. The melted portion solidifies later on. The solidification occurres in twe ways. One is that taking place in an original crystalline phase and in this case metamictization dees not proceed, the other is that not doing and in this case metamictization proceeds. !ntroduetion Mest of radioactive minerals are in the course of time transformed into a metamict state. In a metamict state lattices are broken down and the minera}s are amorphous, retaining their crystal forms. As the agent causing the metamict state is accepted the irradiation arising from disintegration of the radioactive elements contained in the minerals. Since, however, certain radioactive minerais have not been found in an amorphous state, there must be another agent in the metamicti- zation. Recently, much of the interest in irradiation effects has been aroused by the increasing need for shielding materials suitable for the applications of nuclear science. -
Zircon, Monazite and Other Minerals Used in the Production of Chemical Com- Pounds Employed in the Manufac- Ture of Lighting Apparatus
North Carolina State Library GIFT OF \*J.^. M «v* Digitized by the Internet Archive in 2013 http://archive.org/details/zirconmonaziteot25prat V C*> ttonh Carolina Stat© ^vtef <^ Raleigh NORTH CAROLINA GEOLOGICAL AND ECONOMIC SURVEY JOSEPH HYDE PRATT, State Geologist BULLETIN No. 25 Zircon, Monazite and Other Minerals Used in the Production of Chemical Com- pounds Employed in the Manufac- ture of Lighting Apparatus BY JOSEPH HYDE PRATT, Ph.D. Raleigh, N. 0. Edwards & Broughton Printing Co. State Printers and Binders 1916 GEOLOGICAL BOARD Governor Locke Craig, ex officio chairman Raleigh Frank R. Hewitt Asheville Hugh MacRae Wilmington Henry E. Fries ". Winston-Salem John Sprunt Hill Durham Joseph Hyde Pratt, State Geologist Chapel Hill ^5 LETTER OF TRANSMITTAL Chapel Hill, M". C, October 1, 1915. To His Excellency , Honorable Locke Craig, Governor of North Carolina. Sir :—I have the honor to submit herewith for publication as Bulletin 25 a report on Zircon, Monazite and other Minerals Used in the Pro- duction of Chemical Compounds Employed in the Manufacture of Light- ing Apparatus. There is a renewed interest in the deposits of these min- erals in North Carolina, and the present report takes up not only a description of the localities in which these minerals are found, but is a technical review of the development of the lighting industry. Very truly yours, Joseph Hyde Pratt, State Geologist. ±o 5 ,3 3 2 7 CONTENTS PAGE Introduction 7 Zircon 7 Sources of Zirconia 10 Zircon 10 Baddeleyite 10 Other Zirconia-bearing Minerals 11 Occurrences and localities of Zircon 13 Zircon from Henderson County, N. -
Updated 2012
American Federation of Mineralogical Societies AFMS Approved Reference List of Lapidary Material Names “Gem List” August 1996 Updated January 2003 AFMS Pubications Committee B. Jay Bowman, Chair Internet version of Approved Lapidary Material Names. This document can only be downloaded at http://www.amfed.org/rules APPROVED NAMES FOR LAPIDARY LABELS Prepared by the American Federation Nomenclature Committee and approved by the American Federa- tion Uniform Rules Committee, this list is the authorized guide and authority for Lapidary Label Names for exhibitors and judges in all competition under AFMS Uniform Rules. All materials are listed alpha- betically with two columns on a page. The following criteria are to assist in the selection and judging of material names on exhibit labels. 1. The name of any listed material (except tigereye), which has been cut to show a single chatoyant ray, may be preceded by “CAT’S-EYE”; the name of any material which has been cut to show asterism (two or more crossed rays) may be preceded by “STAR”, i.e.: CATS-EYE DIOPSIDE, CAT’S-EYE QUARTZ, STAR BERYL, STAR GARNET, etc. 2. This list is not all-inclusive as to the names of Lapidary materials which may at some time be exhibited. If a mineral or rock not included in this list is exhibited, the recognized mineralogical or petrological name must be used. The names of valid minerals and valid mineral varieties listed in the latest edition of the Glossary of Mineral Species by Michael Fleisher, or any other authorized reference, will be acceptable as Lapidary names. Varieties need only have variety name listed and not the root species. -
Jewellery Series Part I. Cameos
Jewellery Victorian lava cameo bracelet. Seven vari- coloured oval panels depicting various Oval shell cameo brooch of the goddess Nix classical deities and heroes. Sold, together riding an airborne bat, holding two peacock with other lava jewellery, Bonhams Oxford, feathers, in gold mount with rope twist. Sold June 2007, £520. Carved shell brooch. Sold Bonhams Oxford, Bonhams Oxford, June 2007, £1,150. June 2007, £300. Jewellery Series Part I. Cameos by Zita Thornton Souvenirs bought by tourists visiting Rome, most likely on one of the new ‘Cook’s Tours’ in the nineteenth century, inspired the Victorian fashion for cameo jewellery. Following in the footsteps of earlier aristocratic travellers doing the ‘Grand Tour’, the new wealthy middle classes sought cultural enrichment by visiting the ancient sites in Rome and Pompeii. These tourists were not quite wealthy enough to commission a Neo-Classical sculpture or bust so craftsmen satisfied their appetite for classical art by reviving the ancient tradition widely used in Rome and Greece of carving cameos. Ancient cameos were, and still are, highly prized. Their ancient images portrayed important social customs, events and figures. Wearing a cameo was a means of showing loyalty and they were worn by men as well as women. In 2004 Sotheby’s sold an important Roman cameo, from the first or second century for £78,000. The form of a horse had been carved in sardonyx and set in a Murghal jade button in the seventeenth century. The Murghals greatly appreciated cameos. They were presented to princes and emperors. Their popularity only lessened with the decline of the Murghal court itself. -
EFFECTS of SILLIMANITE-GRADE MET AMORPHISM and SHEARING on Nb-Ta OXIDE MINERALS in GRANITIC PEGMATITES
699 Canadian Mineralogist Vol. 30, pp. 699-718 (1992) EFFECTS OF SILLIMANITE-GRADE METAMORPHISM AND SHEARING ON Nb-Ta OXIDE MINERALS IN GRANITIC PEGMATITES: MARS(KOV, NORTHERN MORAVIA, CZECHOSLOVAKIA PETR CERNY Department of Geological Scien ces, Un iversity of Man itoba, Winnipeg, Man itoba R3T 2N2 MILAN NOVAK Department of Mineralogy and Petrography, Moravian Museum, Ze/ny trh 6, 65937 Brno, Czechoslovakia RON CHAPMAN Department of Geological Scien ces, Un iversity of Manitoba, Winnipeg, Man itoba R3T 2N2 ABSTRACT The (Be,Nb,Ta)-bearing albite-muscovite pegmatites at Mar5ikov, in the Hruby Jesenik Mountains pegmatite field of northern Moravia, Czechoslovakia, were subjected to a two-stage, sillimanite-grade, regional metamorphism that reached about 600°C and 4-6 kbar, P(total) > > P(fluid). The first stage generated chrysoberyl at the expense of beryl, under relatively static conditions (pegmatite 1), whereas extensive shearing during a second stage produced a second generation of chrysoberyl, abundant sillimanite and a foliation (pegmatite III). The primary assemblage of the Nb-Ta oxide minerals consisted of manganocolumbite-manganotantalite displaying oscillatory zoning in terms of Nb and Ta, replaced by fersmite and rnicrolite (rarely pyrochlore). The columbite-tantalite was first recrystallized into "bird's-eye" oscillatory-zoned textures or heterogeneous granular aggregates. The original range of Ta/(Ta + Nb) values was commonly reduced, although locally expanded by contribution of additional Nb or Ta from incipient breakdown of fersrnite or microlite, respectively. Mn/(Mn +Fe) largely decreased, by as much as 0.40, by introduction of Fe from the host hornblende gneiss; Mg and Ti also were enriched. -
Mineral Resources of Western
MINERAL RESOURCES OF WESTERN AUSTRALIA DEPARTMENT OF MINES PERTH, WESTERN AUSTRALIA 1980 Issued under the authority of the Hon. P. V. Jones, M.L.A. Minister for Mines 89686-1 Since the publication of the last issue of this booklet in 1966 a major expansion of mineral production in Western Australia has been achieved. Deposits of iron, nickel, natural gas, bauxite, heavy mineral sands, uranium and diamond are now being worked or are known to be commercial. Over the period 1966 to 1971, following the initial discovery of nickel sulphide at Kambalda, a speculative boom in base metal exploration developed that could only be likened to the gold rush days around the turn of the century. Although not all of the exploration activity in this period was well directed, many new discoveries were made as a result of the ready availability of risk capital. In the wake of the boom it is mainly the true prospectors that remain-the individual, to whom the still sparsely populated areas of the State hold an irresistible appeal and the chance of rich bonanza, and the established and dedicated mining companies for whom exploration is a necessary and vital part of the minerals industry. 1 am confident that the persistence of these prospectors will be rewarded with yet further discoveries of economic mineral deposits. Western Australia, with an area of over 2.5 million square kilometres, has a wide diversity of rocks representing all geological periods, and vast areas have been incompletely prospected. This booklet presents an up to date account of the minerals that are, or have been, economically exploited in Western Australia.