 | | Journal (article/letter/editorial) | | world’s oldest emerald deposit occurs in the Gravelotte-Leydsdorp area of the Limpopo Province of South...the vicinity of the town of Leydsdorp, close to Gravelotte, in the Limpopo Province of South Africa. Geologically...Murchison Greenstone Belt showing the location of Gravelotte and Leydsdorp (after Poujol and Robb, 1999)....deposit of the Cobra Pit, under the name of Gravelotte Emerald Mines (GEM), subsequently producing a steady...1982, the total recorded emerald production from Gravelotte was reported as nearly 113 million carats with |  | Jaguin, Justine, Boulvais, Philippe, Poujol, Marc, Bosse, Valérie, Paquette, Jean-Louis, Vilbert, David (2013) Albitization in the Antimony Line, Murchison Greenstone Belt (Kaapvaal Craton): A geochemical and geochronological investigation. Lithos, 168. 124-143 doi:10.1016/j.lithos.2013.01.010 | Journal (article/letter/editorial) | | Rennes - UMR CNRS 6118, OSUR, 35042 Rennes Cedex, France UMR CNRS 6524, Laboratoire Magmas et Volcans, Université...Université Blaise Pascal, 63038 Clermont-Ferrand Cedex, France a r t i c l e i n f o Article history: Received...Line 2.97 (2) D MONARCH 3.23 (1) 2.97 (4) GRAVELOTTE (1) Poujol et al., 1996 >2,90 (1), ≥2.92 (5)...leucogranite Silwana amphibolites Cap Town 200km La France Formation Proterozoic cover (Transvaal) Mashishimale...sedimentary rocks of the MGB to the generic name of Gravelotte Group, subsequently divided into Formations described |  | | Journal (article/letter/editorial) | | depositsrounditc occurs in a latepyrite-bearing calcite vein(Johansson, formattheabovetemperatures, lowpressure...Canada(Sealetal., 1988). vanandAndrS•,1994),andtheAlpha-Gravelotte mine,South Interestingly, theprincipal mineral...andcinnabar arepresentin trace amounts Gangue:quartz,calcite,sericite, barite, fluorite, kaolinitc, and Murchison...between 150 ø and 200øC Haut Allier, Massif Central, France Bril (1982), Bril and Beaufort (1989), Bril et...ore fluid Massiacdistrictof the MassifCentral of France, Bril (1982) (meteoric and,therefore, oxidizing) |  | Hazen, R. M., Golden, J., Downs, R. T., Hystad, G., Grew, E. S., Azzolini, D., Sverjensky, D. A. (2012) Mercury (Hg) mineral evolution: A mineralogical record of supercontinent assembly, changing ocean geochemistry, and the emerging terrestrial biosphere. American Mineralogist, 97 (7) 1013-1042 doi:10.2138/am.2012.3922 | Journal (article/letter/editorial) | | mindat.org records more than 300 separate mercury mines, prospects, dumps, placers, and other localized...California; (b) cinnabar (HgS), RRUFF 070532, on calcite from Charcas, San Luis Potosi, Mexico; (c) imiterite...imiterite (Ag2HgS2), RRUFF 080014, with calcite and dolomite from Imiter, Morocco; (d) silver var. amalgam...amalgam (Ag,Hg), RRUFF 070463, with malachite and calcite, from the Tsumeb mine, Namibia. in the famous...Kříbek et al. (2009) FR01 France Roua Mines, Alpes Maritimes, Provence-Alpes-Côtes d’Azur Sarp et al. |  | | Journal (article/letter/editorial) | | H20-CH&02-NaCl system during emerald mineralization at Gravelotte, Murchison Greenstone Belt, Northeast Transvaal...A~~t-~~d evolution during emeraId inception at the Gravelotte emerald mine has been studied by mi~~e~ornet~...and a later phase of regional me~mo~hism. THE GRAVELOTTE AREA LIES along the southern margin of the Archean...theories have been advanced for the genesis of the Gravelotte emeralds ( ROBB and ROBB, 1986; GRUNDMANN and...emerald mineralization. Up to a few years ago the Gravelotte Emerald Mine (GEM) in this area accounted for |  | | Journal (article/letter/editorial) | | 2017.5.2, RSA1, RSA2, RSA3, RSA4 Gravelotte Emerald Mine, Gravelotte, Murchison Range, Limpopo Province...details regarding main deposits and individual mines, general geology, metamorphic facies, temperature...the discussion. billion-year-old host rocks (Gravelotte deposit; ref. [29]) also have trace element patterns...in nearly three-billion-year-old host rocks (Gravelotte deposit; [29]) also have trace element patterns...here. Similarly, some emeralds appear to have calcite or organic inclusions, such as RSA5 and RSA6, whereas |  | Giuliani, Gaston, Groat, Lee A., Marshall, Dan, Fallick, Anthony E., Branquet, Yannick (2019) Emerald Deposits: A Review and Enhanced Classification. Minerals, 9 (2) 105 doi:10.3390/min9020105 | Journal (article/letter/editorial) | | Notre-Dame des Pauvres, BP 20, 54501 Vandœuvre cedex, France Department of Earth, Ocean and Atmospheric Sciences...7327-CNRS/Université d’Orléans/BRGM, 45071 Orléans, France; yannick.branquet@univ-orleans.fr Correspondence:...ct) and Emilia (7025 ct), both from the Gachalá mines. In 2017, a large piece of biotite schist with several...16: Lened; 17. Tsa da Gliza. South Africa: 18. Gravelotte. Zimbabwe: 19. Sandawana, Masvingo, Filibusi...matter, as well as tiny fragments of quartz and calcite. Figure 9. Potential geological sources of chromium |  | | Journal (article/letter/editorial) | | range in transparency and zoning. (a) 29GRVB, Gravelotte, South Africa, IR = 1; (b) 98LL, Lorelei, South...alteration. Propylitic alteration (chlorite + epidote + calcite) is peripheral to phyllic/argillic alteration and...aggregate also has calcite in the vein and intergrown with the molybdenite. Calcite in porphyry deposits...to have been incorporated or absorbed into the calcite intergrowths, with 5.45 wt% Re present. Chrislmas...examined to evaluate Re loss from weathering. Gravelotte, South Africa Morenci Mine, AZ %BR*wt %Re IR |  | | Report (issue) | | Hampton, CT Editors Dr. Gaston Giuliani, Nancy, France Dr. Miranda Jarnot, Annandale, VA Dr. Gunther Neumeier...Germany Cover A 6.5 cm emerald specimen with calcite from Coscuez, Boyaca, Colombia. Bill Larson collection;...and Bernard Charoy from CRPGICNRS in Vandoeuvre, France Colombia: Gonzalo Jara of Bogota, Colombia Africa:...word beryl found its way into our languages. In France, the Latin word gave birth to the verb briller...small, perforated emeralds, proba bly from the mines at Sikait, was found in the ruins of Pompeii and |  | | Journal (article/letter/editorial) | | are 25 and 5 wt.%, respectively. Mg-calcite, magnesite, calcite and aragonite are also identified as...apatite, stilbite, molybdenite, pyrite, fluorite and calcite commonly occur in pegmatites (Kazmi and Snee, 1989)...whereas stilbite, molybdenite, pyrite, fluorite and calcite are later minerals (Correia Neves, 1978). It was...can easily be distinguished (Burke, 1994); thus calcite, Mgcalcite, aragonite and magnesite were found...nahcolite inclusion. (d) Fluid inclusion with calcite and nahcolite daughter phases. (e) Fluid inclusion |  | | Book (edition) | | these may help with problems of identification. Mines vary in their recep tion of amateurs. Most are...should be borne in mind that searching in disused mines can be dangerous; likewise, caves may be unsafe...attached list of working mines. The geological map of Namibia which shows the mines and also farm boundaries...or possibly few and far between. Localities of mines or formations of specific geological interest are...2 3 4 5 6 7 8 9 10 talc (the softest) gypsum calcite fluorspar apatite feldspar quartz topaz corundum |  | | Book | | and Prof. R. W. Hutchinson (Colorado School of Mines, Golden, USA) for their critical and constructive................. .40 3.1.4 Vaulry, Haute Vienne, France ............................................................... 41 3 .1.5 Charrier, Allier, France .....................................................Clochettes, Lautaret, Hautes Alpes, France ................................. 86 3.4.9 Saint-Martin-la-Sauvete District...District, Loire, France ................................. 86 3.4.10 Kutna Hora, Czech Republic ..... |  | | Journal (article/letter/editorial) | | Pauvres, BP 20, 54501 Vandœuvre-lès-Nancy Cedex, France Department of Earth Sciences, Simon Fraser University... However there is speculation that the emerald mines in Colombia are becoming depleted. Brazil currently...(Ward, 2001). There is speculation that the emerald mines in Colombia are becoming depleted and there is pressure...Rb/Sr geochemistry, the mineralization at the two mines is coeval. The original Colombian emerald deposits...by development of a vein system filled by fibrous calcite, bitumen, and pyrite. The second stage was characterized |  | | Journal (article/letter/editorial) | | Colombian emeralds are related to quartzo--feldspathic calcite veins of Tertiary age which intrude carbonaceous...In the Murchison Range of South Africa, at the Gravelotte deposit, the mineralised zones occur close to...been emplaced at ~ 2650 Ma (Bohmke, 1982). The Gravelotte mineralisation occurs in the Archaean Kapvaal...grateful to the Permanent Secretary, Ministry of Mines, Dr. E.H.B. Mwanang'onze and the Chief Geologist...Rhodesian emeralds and chrysoberyls. J. Chamber. Mines S. Rhodesia, 4, No. 10: 34--38. Mendelsohn, F. (Editor) |  | | Journal (article/letter/editorial) | | between aluminum in varved of carbon pH and calcite-saturation models of mantle metasomatism from...conditions and state and sulphide segregation: at Gravelotte. documented potassic Murchison in a composite |  | Groat, L. A., Marshall, D. D., Giuliani, G., Murphy, D. C., Piercey, S. J., Jambor, J. L., Mortensen, J. K., Ercit, T. S., Gault, R. A., Mattey, D. P., Schwarz, D., Maluski, H., Wise, M. A., Wengzynowski, W., Eaton, D. W. (2002) MINERALOGICAL AND GEOCHEMICAL STUDY OF THE REGAL RIDGE EMERALD SHOWING, SOUTHEASTERN YUKON. The Canadian Mineralogist, 40 (5) 1313-1338 doi:10.2113/gscanmin.40.5.1313 | Journal (article/letter/editorial) | | Pauvres, BP 20, F-54501 Vandœuvre-lès-Nancy Cedex, France DONALD C. MURPHY Yukon Geology Program, Government...2, Place Eugène Bataillon, F-34095 Montpellier, France MICHAEL A. WISE Smithsonian Institution, Mineral...solid and fluid inclusions; the former include calcite, chalcopyrite, molybdenite, phlogopite, pyrite...beryl have been found encapsulated in hydrothermal calcite. Numerous examples of beryl in association with...inclusions have been observed in emerald from the Gravelotte (South Africa; Nwe & Morteani 1993), Franqueira |  | | Journal (issue) | | country’s emerald-related bodies and the Ministry of Mines and Energy, the symposium addressed the challenges...field visit to the country’s best-know emerald mines by 30 participants, including geologists, gemologists... They visited the Muzo, Cunas, Pita and Chivor mines on the slopes of the Andean Mountains and received...Dreams Flying Into The Heart of Colombia’s Emerald Mines Education 44 50 Education and the Mine-to-Market...World, Similarities And Differences The Emerald Mines of the Panjshir Valley, Afghanistan Emeralds in |  | Salvi, Stefano, Giuliani, Gaston, ANDRIANJAKAVAH, Prosper Rakatovao, Moine, Bernard, Beziat, Didier, Fallick, Anthony (2017) Fluid Inclusion and Stable Isotope Constraints On the Formation of the Ianapera Emerald Deposit, Southern Madagascar. The Canadian Mineralogist, 55 (4) 619-650 doi:10.3749/canmin.1700017 | Journal (article/letter/editorial) | | 5563, 14 avenue Edouard Belin, F-31400 Toulouse, France GASTON GIULIANI Université Paul Sabatier, GET...5563, 14 avenue Edouard Belin, F-31400 Toulouse, France and Université de Lorraine, CRPG UMR 7358 CNRS-UL...Notre-Dame-des-Pauvres, BP20, 54501 Vandœuvre-lès-Nancy cedex, France PROSPER RAKATOVAO ANDRIANJAKAVAH Université Paul...Belin, F-31400 Toulouse, France BERNARD MOINE Piac, F-82400 Valence-d’Agen, France DIDIER BEZIAT Université...5563, 14 avenue Edouard Belin, F-31400 Toulouse, France ANTHONY FALLICK Isotope Geosciences Unit, S.U |  | | Journal (article/letter/editorial) | | excav&tions DISCOVERY PIT FIG.3. Leydsdorp-Gravelotte emeraldmine.Geologic mapof theareasurrounding...0.1 to 1 Antigorite-serpentinite 1.9 1 7 Calcite-epidoterock Plagioclasegneisses (type I, prealpine...formationin regionalmetamorphism: Case studiesfrom Gravelotte, South Africa and Ha- bachtal,Austria[abs.]:Terra |  | | Journal (issue) | | BRITAIN ASSOCIATION GEMMOLOGICAL OF GREAT BRITAIN SAINT DUNSTAN'S HOUSE, CAREY LANE LONDON, EC2V 8AB GEMMOLOGICAL...F.G.A. Assistant Secretary: D. Wheeler, F.G.A. Saint Dunstan's House, Carey Lane, London EC2V SAD (By...being 20 eV/channel). Emerald In Figure 4, a Gravelotte emerald and a synthetic Gilson emerald are compared...characteristic content of traces and minor elements in Gravelotte emerald is obvious. Unfortunately inclusions...s t ha l f 10.21 Energy spectrum of natural Gravelotte emerald, lower half of spectrum. S i Ko d iff |  | Vapnik, Ye., Moroz, I., Roth, M., Eliezri, I. (2006) Formation of emeralds at pegmatite-ultramafic contacts based on fluid inclusions in Kianjavato emerald, Mananjary deposits, Madagascar. Mineralogical Magazine, 70 (2) 141-158 doi:10.1180/0026461067020320 | Journal (article/letter/editorial) | | hornblende-chlorite-phlogopiteemerald-plagioclase-calcite-quartz assemblages. Phlogopite has been dated at...Raman probe data (Fig. 10) indicate that calcite, Mg-calcite, magnesite and dolomite are the usual solid...¯uid inclusion demands the ¯uid/calcite volume ratio of ~103, if all calcite precipitates in the inclusion...realistic: the experiments suggest that the ¯uid/calcite volume ratio for natural vein formation may in...contain single or several daughter phases of calcite, Mg-calcite, magnesite and dolomite. Nahcolite is found |  | | Journal (issue) | | BRITAIN GEMMOLOGICAL ASSOCIATION OF GREAT BRITAIN SAINT DUNSTAN'S HOUSE, CAREY LONDON, E.C.2 LANE GEMMOLOGICAL...Director of Examinations: G. F. Andrews Offices: Saint Dunstan's House, Carey Lane, London, E.C.2 Telephone...pale. Pyrite crystals and three-phase inclusions. Calcite and three-phase inclusions. Actinolite blades and...common to them from the Muso stones, which have calcite r h o m b inclusions and occasionally pink rare...to 2-71 and double refraction of -006, and have calcite as an inclusion but three-phase inclusions as well |  | | Journal (article/letter/editorial) | | 1978; Davies et al. 1986) contains the Alpha-Gravelotte, Beta-Jack Section, Athens and Monarch-Free State...plunge continuities of at least 900 m. Individual mines and orebodies are centered on structural inhomogeneities...variable, chloritization and carbonatization (calcite±ankerite) in distal alteration zones. In proximal...Relationship of fluid inclusions trapped in quartz and calcite crystals to stibnite-gold mineralization Stibnite...occurs only rarely in distal quartz-calcite veinlets. Quartz or calcite crystals are generally millimeter |  | | Book | | Childbirth, and Fertil78 ity, Fevers and 131 France, 77 127 130 Italy, Poisons and Venomous Bites...438 339 438 Finland, 438 Early Magmatic, 339 France, French Beryl Disseminations in Granite, 339 ...Dr. Paris, Museum (Natural Chatham, British France; San Francisco, Campagne measure les Phoenix...E. NY; XV Foord, Wardreques, Pas de Calais, France; Johansen, New York, Idarlibrar- Tempe, AZ;... precious about or Egypt, Ball, the emerald mines to the 2000-1788 period decorative alike resulted |  | | Report (issue) | | in the Pala, Mesa Grande, and Ramona districts. Mines that have been successfully reopened include the...Hercules in Ramona. In addition, a number of new mines have produced gem and specimen material, particularly...populated, and the exact location of many older mines and prospects is uncertain. Perhaps the best-known...individual pegmatite dikes. Over the years, numerous mines and prospects have been established on pegmatites...tourmaline, gem spodumene, and pink beryl. Most of the mines in the Pala district are located within the boundaries |
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