Spring 2000 Gems & Gemology
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Chemical Composition of Mn-And Cl-Rich Apatites from the Szklary
minerals Article Chemical Composition of Mn- and Cl-Rich Apatites from the Szklary Pegmatite, Central Sudetes, SW Poland: Taxonomic and Genetic Implications Adam Szuszkiewicz 1,* ID , Adam Pieczka 2, Bozena˙ Goł˛ebiowska 2, Magdalena Duma ´nska-Słowik 2 ID , Mariola Marszałek 2 and Eligiusz Szeł˛eg 3 1 Institute of Geological Sciences, University of Wrocław, pl. M. Borna 9, 50-204 Wrocław, Poland 2 Department of Mineralogy, Petrography and Geochemistry, AGH University of Science and Technology Mickiewicza 30, 30-059 Kraków, Poland; [email protected] (A.P.); [email protected] (B.G.); [email protected] (M.D.-S.); [email protected] (M.M.) 3 Department of Geochemistry, Mineralogy and Petrography, Faculty of Earth Sciences, University of Silesia, B˛edzi´nska60, 41-200 Sosnowiec, Poland; [email protected] * Correspondence: [email protected] Received: 6 July 2018; Accepted: 9 August 2018; Published: 14 August 2018 Abstract: Although calcium phosphates of the apatite group (apatites) with elevated contents of Mn are common accessory minerals in geochemically evolved granitic pegmatites, their Mn-dominant M1 M2 X analogues are poorly studied. Pieczkaite, Mn2 Mn3(PO4)3 Cl, is an exceptionally rare Mn analogue of chlorapatite known so far from only two occurrences in the world, i.e., granitic pegmatites at Cross Lake, Manitoba, Canada and Szklary, Sudetes, SW Poland. In this study, we present the data on the compositional variation and microtextural relationships of various apatites highly enriched in Mn and Cl from Szklary, with the main focus on compositions approaching or attaining the stoichiometry of pieczkaite (pieczkaite-like apatites). -
The Journal of Gemmology Data Depository Photomicrographs To
The Journal of Gemmology Data Depository Photomicrographs to accompany the article: Hänni H.A., Brunk R. and Franz L. 2021. An investigation of grinding hardness of some ornamental stones. Journal of Gemmology, 37(6), 2021, 632–643, https://doi.org/10.15506/JoG.2021.37.6.632. The following photomicrographs of thin sections of the samples were made with a Leica DFC490 camera mounted on a Leica DMRD polarising microscope with transmitted light. For each sample, figure A shows the sample in plane-polarised light (II Pol.) and figure B with crossed polarisers (X Pol.); the sample numbers correspond to those in the article. Photomicrographs © L. Franz. 1 1 Aventurine quartz, green: Foliated matrix with aligned quartz (Qz) grains, fuchsite (Fu) tablets and accessory zircon (Zrn). 2 2 Aventurine quartz, orangey red: Mylonitic fabric with quartz (Qz) ribbons and recrystallized grains as well as intergrowths of muscovite with hematite (Ms & Hem). 3 3 Chalcedony, light grey: Intensely interlocked chalcedony (Chc) crystals with random orientation. 4 4 Chrysoprase: In a matrix of tiny chalcedony (Chc) and quartz (Qz) crystals, larger quartz aggregates occur. In microfractures, palisade-shaped chalcedony crystals and quartz grains formed. 5 5 Dumortierite: A banded texture with layers rich in dumortierite (Dum), dumortierite and quartz (Dum & Qz), quartz (Qz) and tourmaline (Tur). 6 6 Granite: The holocrystalline fabric is made up of subhedral plagioclase (Pl), orthoclase (Or), biotite (Bt) and anhedral quartz (Qz). 7 7 Green quartz: A granoblastic texture made up of large quartz (Qz) crystals as well as a microfolded layer of fuchsite (Fu). 8 8 Heliotrope (bloodstone): Green, brown and colourless accumulations of chalcedony (Chc) are recognizable. -
Magnetic Susceptibility Index for Gemstones ©2010 Kirk Feral Magnetic Responses Are Standardized to 1/2" X 1/2" N-52 Magnet Cylinders
Magnetic Susceptibility Index for Gemstones ©2010 Kirk Feral Magnetic responses are standardized to 1/2" X 1/2" N-52 magnet cylinders. Colorless and extremely pale stones of any species tend to be Inert (diamagnetic). Black opaque stones of many species are strongly magnetic and may Pick Up or Drag. Pick Up and Drag responses are weight-dependent. Direct responses on the Index apply to gems 1-4cts. Larger gems may be too heavy to Pick Up or Drag. Smaller non-Garnet gems with strong magnetism may Pick Up. Gemstone Response Range SI X 10 (-6) Range Cause of Color Actinolite Nephrite Jade (black) Strong to Drags 321-577 SI Iron Nephrite Jade (green) Moderate to Drags 91-343 Iron, Chromium Nephrite Jade (white, yellow) Inert < 0 (diamagnetic) Iron Pargasite (green) Inert < 0 (diamagnetic) Iron, Vanadium Pargasite (orangey brown) Weak 35 SI Iron Afghanite (blue) Inert < 0 (diamagnetic) Chromium, Vanadium Amber (any color) Inert < 0 (diamagnetic) Charge Transfer involving Organic Compounds Amblygonite-Montebrasite (blue, green) Inert < 0 (diamagnetic) Iron, Manganese Andalusite Inert to Weak < 0 -26 Iron-Oxygen-Titanium Charge Transfer Apatite Transparent blue, green, yellow Inert (Weak in rare cases) < 0 (diamagnetic) Mang., Rare-earth, Charge Transfer, Color Centers Cat's eye translucent yellow, yellowish brown Weak to Strong < 20 - >120 Rare-earth Metals Astrophyllite Strong 1146-1328 Iron, Manganese Axinite Drags 603-616 SI Iron Azurite (opaque) Strong 382 SI Copper Barite (pale brown, blue) Inert < 0 (diamagnetic) Color Centers Bastnasite -
An Exploration of Jade Maria Jones
Eastern Michigan University DigitalCommons@EMU Senior Honors Theses Honors College 2004 An Exploration of Jade Maria Jones Follow this and additional works at: http://commons.emich.edu/honors Recommended Citation Jones, Maria, "An Exploration of Jade" (2004). Senior Honors Theses. 85. http://commons.emich.edu/honors/85 This Open Access Senior Honors Thesis is brought to you for free and open access by the Honors College at DigitalCommons@EMU. It has been accepted for inclusion in Senior Honors Theses by an authorized administrator of DigitalCommons@EMU. For more information, please contact lib- [email protected]. An Exploration of Jade Abstract Abstract: This is a research paper studying the history of Jade carving during the Chinese Han Dynasty from 206 B.C to 220 A.D. The ap per explains the meaning of jade to the Chinese people and examines the origin of the precious stone for the Han people and other generations of dynasties. There is an accurate telling of Han beliefs followed by a descriptive passage on the history of religious influence on the Han people. There is an extensive study on the history of the Han people in general and a lengthy report on the different forms of jade and their functions for the Han people. Degree Type Open Access Senior Honors Thesis Department Art First Advisor Dr. Richard Rubenfeld Second Advisor Leslie Atzmon Keywords Jade art objects, Art objects, Chinese, Jade This open access senior honors thesis is available at DigitalCommons@EMU: http://commons.emich.edu/honors/85 AN EXPLORATION OFJ/\DL: by :'vlariaJones A St~nior ThcsIs Submitted to the !:astern tv1ichigan Umversny 1ionors Program In Partial Fulfillment of the Requiremems for Graduation With Honors in Fine Art: CcHJCcntratinnin Graphic Design 1 I I ! ~--'~""'-"""'- ,,=.. -
English-Spanish (Dictionnaire)
English−spanish (dictionnaire) English−spanish Dictionary éditions eBooksFrance www.ebooksfrance.com English−spanish Dictionary 1 English−spanish (dictionnaire) Adapted from : http://www.freedict.com/dictionary/index. -
Economic Dimensions of Precious Metals, Stones, and Feathers: the Aztec State Society
ECONOMIC DIMENSIONS OF PRECIOUS METALS, STONES, AND FEATHERS: THE AZTEC STATE SOCIETY FRANCES F. BERDAN In the spring of 1519, Hernán Cortés and his band of Spanish conquistadores feasted their eyes on the wealth of an empire. While resting on the coast of Veracruz, before venturing inland, Cortés was presented with lavish gifts from the famed Aztec emperor Mocte· zuma IV- While only suggestive of the vastness of imperial wealth, these presents included objects of exquisite workmanship fashioned of prized materials: gold, silver, feathers, jadeite, turquoise.2 There was an enormous wheel of gold, and a smaller one of silver, one said to represent the sun, the other the moon. There were two impressive collars (necklaces) of gold and stone mosaic work: they combined red stones, green stones, and gold bells. s There were fans and other elabo 1 Saville (1920: 20-39, 191-206) provides a detailed summary of the many accounts of the gifts presented to Cortés on this occasion. 2 Up to this point in their adventure, sorne of the conquistadores apparently had been sorely disappointed in the mainland's wealth. Bernal Diaz del Castillo repeatedly refers to the gold encountered by the Hernández de Córdova and Gri jalva expeditions (1517 and 1518, respectively) as "Iow grade" or "inferior", and small in quantity (Díaz del Castillo, 1956: 8, 22,23, 25, 28). While Díaz, writing many years after the events he describes, seems especially critical of the quality of the gold avaiJable on the coast, the friar Juan Díaz's account of the Grijalva ex pedition betrays no such dísappointment. -
Mineral Processing
Mineral Processing Foundations of theory and practice of minerallurgy 1st English edition JAN DRZYMALA, C. Eng., Ph.D., D.Sc. Member of the Polish Mineral Processing Society Wroclaw University of Technology 2007 Translation: J. Drzymala, A. Swatek Reviewer: A. Luszczkiewicz Published as supplied by the author ©Copyright by Jan Drzymala, Wroclaw 2007 Computer typesetting: Danuta Szyszka Cover design: Danuta Szyszka Cover photo: Sebastian Bożek Oficyna Wydawnicza Politechniki Wrocławskiej Wybrzeze Wyspianskiego 27 50-370 Wroclaw Any part of this publication can be used in any form by any means provided that the usage is acknowledged by the citation: Drzymala, J., Mineral Processing, Foundations of theory and practice of minerallurgy, Oficyna Wydawnicza PWr., 2007, www.ig.pwr.wroc.pl/minproc ISBN 978-83-7493-362-9 Contents Introduction ....................................................................................................................9 Part I Introduction to mineral processing .....................................................................13 1. From the Big Bang to mineral processing................................................................14 1.1. The formation of matter ...................................................................................14 1.2. Elementary particles.........................................................................................16 1.3. Molecules .........................................................................................................18 1.4. Solids................................................................................................................19 -
Chromite Crystal Structure and Chemistry Applied As an Exploration Tool
Western University Scholarship@Western Electronic Thesis and Dissertation Repository February 2015 Chromite Crystal Structure and Chemistry applied as an Exploration Tool Patrick H.M. Shepherd The University of Western Ontario Supervisor Dr. Roberta L. Flemming The University of Western Ontario Graduate Program in Geology A thesis submitted in partial fulfillment of the equirr ements for the degree in Master of Science © Patrick H.M. Shepherd 2015 Follow this and additional works at: https://ir.lib.uwo.ca/etd Part of the Geology Commons Recommended Citation Shepherd, Patrick H.M., "Chromite Crystal Structure and Chemistry applied as an Exploration Tool" (2015). Electronic Thesis and Dissertation Repository. 2685. https://ir.lib.uwo.ca/etd/2685 This Dissertation/Thesis is brought to you for free and open access by Scholarship@Western. It has been accepted for inclusion in Electronic Thesis and Dissertation Repository by an authorized administrator of Scholarship@Western. For more information, please contact [email protected]. Western University Scholarship@Western University of Western Ontario - Electronic Thesis and Dissertation Repository Chromite Crystal Structure and Chemistry Applied as an Exploration Tool Patrick H.M. Shepherd Supervisor Roberta Flemming The University of Western Ontario Follow this and additional works at: http://ir.lib.uwo.ca/etd Part of the Geology Commons This Thesis is brought to you for free and open access by Scholarship@Western. It has been accepted for inclusion in University of Western Ontario - Electronic Thesis and Dissertation Repository by an authorized administrator of Scholarship@Western. For more information, please contact [email protected]. Chromite Crystal Structure and Chemistry Applied as an Exploration Tool (Thesis format: Integrated Article) by Patrick H.M. -
Christie's Presents Jewels: the Hong Kong Sale
FOR IMMEDIATE RELEASE October 28, 2008 Contact: Kate Swan Malin +852 2978 9966 [email protected] CHRISTIE’S PRESENTS JEWELS: THE HONG KONG SALE Jewels: The Hong Kong Sale Tuesday, December 2 Christie’s Hong Kong Hong Kong – Christie’s announces the fall sale of magnificent jewellery, Jewels: The Hong Kong Sale, which will take place on December 2 at the Hong Kong Convention and Exhibition Centre. This sale features an exquisite selection of over 300 extraordinary jewels across a spectrum of taste and style, from masterpieces of the Belle Époque to contemporary creations, and from the rarest of white and coloured diamonds to important coloured stones. COLOURLESS DIAMONDS Leading the auction is a rare pair of D colour, Flawless diamonds weighing 16.11 and 16.08 carats (illustrated right, estimate: HK$40,000,000-60,000,000 / US$5,000,000-8,000,000). These marvellous stones are also graded ‘Excellent’ for polish, symmetry and cut grade, making them exceedingly rare for their superb quality. Classified as Type IIa, these diamonds are the most the chemically pure type of diamonds known, with no traces of the colorant nitrogen. The absence of this element, seen in 98% of diamonds, gives these stones a purity of colour and degree of transparency that is observed only in the finest white diamonds. The modern round brilliant cut is the diamond’s most basic and popular shape, as it allows the potential for the highest degree of light return. But more importantly, the round diamond sustains the highest value as its production requires riddance of the greatest amount of diamond rough. -
List of New Mineral Names: with an Index of Authors
415 A (fifth) list of new mineral names: with an index of authors. 1 By L. J. S~v.scs~, M.A., F.G.S. Assistant in the ~Iineral Department of the,Brltish Museum. [Communicated June 7, 1910.] Aglaurito. R. Handmann, 1907. Zeita. Min. Geol. Stuttgart, col. i, p. 78. Orthoc]ase-felspar with a fine blue reflection forming a constituent of quartz-porphyry (Aglauritporphyr) from Teplitz, Bohemia. Named from ~,Xavpo~ ---- ~Xa&, bright. Alaito. K. A. ~Yenadkevi~, 1909. BuU. Acad. Sci. Saint-P6tersbourg, ser. 6, col. iii, p. 185 (A~am~s). Hydrate~l vanadic oxide, V205. H~O, forming blood=red, mossy growths with silky lustre. Founi] with turanite (q. v.) in thct neighbourhood of the Alai Mountains, Russian Central Asia. Alamosite. C. Palaehe and H. E. Merwin, 1909. Amer. Journ. Sci., ser. 4, col. xxvii, p. 899; Zeits. Kryst. Min., col. xlvi, p. 518. Lead recta-silicate, PbSiOs, occurring as snow-white, radially fibrous masses. Crystals are monoclinic, though apparently not isom0rphous with wol]astonite. From Alamos, Sonora, Mexico. Prepared artificially by S. Hilpert and P. Weiller, Ber. Deutsch. Chem. Ges., 1909, col. xlii, p. 2969. Aloisiite. L. Colomba, 1908. Rend. B. Accad. Lincei, Roma, set. 5, col. xvii, sere. 2, p. 233. A hydrated sub-silicate of calcium, ferrous iron, magnesium, sodium, and hydrogen, (R pp, R',), SiO,, occurring in an amorphous condition, intimately mixed with oalcinm carbonate, in a palagonite-tuff at Fort Portal, Uganda. Named in honour of H.R.H. Prince Luigi Amedeo of Savoy, Duke of Abruzzi. Aloisius or Aloysius is a Latin form of Luigi or I~ewis. -
Geology and Age of the Lac a La Perdrix Fenite, Southern Gatineau District, Quebec
CA9700383 -4- Geology and age of the Lac a la Perdrix fenite, southern Gatineau district, Quebec D.D. Hogarth1 and Otto van Breemen2 Hogarth, D.D. and van Breemen, 0., 1996: Geology and age of the Lac a la Perdrix fenite, southern Gatineau district, Quebec; inRadiogenic Age and Isotopic Studies: Report 9; Geological Survey of Canada, Current Research 1995-F, p. 33-41. Abstract: The Lac a la Perdrix fenite lies in the Central Metasedimentary Belt of the Grenville Province. This 30 m wide fenite, adjacent to a narrow calciocarbonatite sill, replaces diopside-oligoclase gneiss and is composed of magnesio-arfvedsonite, aegirine, microcline, albite, and fluorapatite. Near the contact with carbonatite, it contains appreciable monazite and barite whereas aegirine virtually disappears. Fenitization probably took place early in the igneous stage of carbonatite development. A Pb/U monazite age of 1026 ± 2 Ma is thought to date fenite formation. Together with published data, this age shows that carbonatite intruded metamorphic rocks near the close of the Grenville Orogeny. Resume : La fenite de Lac a la Perdrix s'observe dans la ceinture metasedimentaire de la Province de Grenville. Cette fenite, mesurant 30 m de largeur et en position adjacente par rapport a un etroit filon-couche de calciocarbonatite, remplace un gneiss a diopside-oligoclase et se compose de magnesio-arfvedsonite, d'aegirine, de microcline, d'albite et de fluorapatite. Pres du contact avec la carbonatite, la fenite contient de la monazite et de la barytine en quantite appreciable, tandis que l'aegirine disparait pratiquement. La fenitisation a probablement eu lieu au debut de l'episode igne durant lequel s'est form6 la carbonatite. -
U.S. Government Printing Office Style Manual, 2008
U.S. Government Printing Offi ce Style Manual An official guide to the form and style of Federal Government printing 2008 PPreliminary-CD.inddreliminary-CD.indd i 33/4/09/4/09 110:18:040:18:04 AAMM Production and Distribution Notes Th is publication was typeset electronically using Helvetica and Minion Pro typefaces. It was printed using vegetable oil-based ink on recycled paper containing 30% post consumer waste. Th e GPO Style Manual will be distributed to libraries in the Federal Depository Library Program. To fi nd a depository library near you, please go to the Federal depository library directory at http://catalog.gpo.gov/fdlpdir/public.jsp. Th e electronic text of this publication is available for public use free of charge at http://www.gpoaccess.gov/stylemanual/index.html. Use of ISBN Prefi x Th is is the offi cial U.S. Government edition of this publication and is herein identifi ed to certify its authenticity. ISBN 978–0–16–081813–4 is for U.S. Government Printing Offi ce offi cial editions only. Th e Superintendent of Documents of the U.S. Government Printing Offi ce requests that any re- printed edition be labeled clearly as a copy of the authentic work, and that a new ISBN be assigned. For sale by the Superintendent of Documents, U.S. Government Printing Office Internet: bookstore.gpo.gov Phone: toll free (866) 512-1800; DC area (202) 512-1800 Fax: (202) 512-2104 Mail: Stop IDCC, Washington, DC 20402-0001 ISBN 978-0-16-081813-4 (CD) II PPreliminary-CD.inddreliminary-CD.indd iiii 33/4/09/4/09 110:18:050:18:05 AAMM THE UNITED STATES GOVERNMENT PRINTING OFFICE STYLE MANUAL IS PUBLISHED UNDER THE DIRECTION AND AUTHORITY OF THE PUBLIC PRINTER OF THE UNITED STATES Robert C.