| Milesi, J.P, Ledru, P, Marcoux, E, Mougeot, R, Johan, V, Lerouge, C, Sabaté, P, Bailly, L, Respaut, J.P, Skipwith, P (2002) The Jacobina Paleoproterozoic gold-bearing conglomerates, Bahia, Brazil: a “hydrothermal shear-reservoir” model. Ore Geology Reviews, 19 (1) 95-136 doi:10.1016/s0169-1368(01)00038-5 | Journal (article/letter/editorial) | com/locate/oregeorev The Jacobina Paleoproterozoic gold-bearing conglomerates, Bahia, Brazil: a ‘‘hydrothermal...widespread alteration with gold-bearing quartz lodes, conglomerates showing a sulphide – gold – Cr – mineral association... Such a model, which implies the existence of a gold preconcentration within the quartz – pebble conglomerates...cataclastic quartz, quartz – pyrite mylonite and rare fuchsite-bearing rocks) that had been hydrothermally altered...postsedimentary mesothermal quartz – tourmaline – muscovite/fuchsite lodes, which constitute a possible source of the | | Teixeira, João Batista Guimarães, de Souza, Jorge André Braz, da Silva, Maria da Glória, Leite, Carlson Matos Maia, Barbosa, Johildo Salomão Figueiredo, Coelho, Carlos Eduardo Silva, Abram, Maisa Bastos, Filho, Valter Mônaco Conceição, Iyer, Sundaram S.S. (2001) Gold mineralization in the Serra de Jacobina region, Bahia Brazil: tectonic framework and metallogenesis. Mineralium Deposita, 36 (3) 332-344 doi:10.1007/s001260100174 | Journal (article/letter/editorial) | MoÃnaco ConceicËaÄo Filho á Sundaram S.S. Iyer Gold mineralization in the Serra de Jacobina region,...Abstract Gold deposits in the Serra de Jacobina region in Bahia, northeastern Brazil, occur in a belt of siliciclastic...ed hydrothermal orebodies, and the formation of gold occurrences also in quartzites and ma®c and ultrama®c...an epigenetic model for the mineralizing event. Gold mineralization is interpreted to be an integral...craton along a main orogenic belt termed the Salvador±CuracËa mobile belt (Marinho and Sabate 1982; Cordani | | Ledru, P., Mile´si, J.P., Johan, V., Sabate´, P., Maluski, H. (1997) Foreland basins and gold-bearing conglomerates: a new model for the Jacobina Basin (Sa˜o Francisco province, Brazil) Precambrian Research, 86 (3) 155-176 doi:10.1016/s0301-9268(97)00048-x | Journal (article/letter/editorial) | PrecambrianResearch 86 (1997) 155-176 Foreland basins and gold-bearing conglomerates: a new model for the Jacobina...belts around 2000 Ma ago. In addition, it contains gold-bearing conglomerates of economic interest that...alteration within mineralized conglomerates (sulphide, fuchsite, tourmaline, chromite, rutile), leaching of ultrabasic...progressive involvement in the Transamazonian collision belt. Resedimentation processes, preservation of earlier...favour a model of epigenetic mineralization for the gold-bearing conglomerates with enrichment during the | | | Journal (article/letter/editorial) | the Prestea Mesothermal Vein Gold Deposit in the Birimian System of Ghana a Napoleon Q. Hammond & Hidehiko...the Prestea Mesothermal Vein Gold Deposit in the Birimian System of Ghana, International Geology Review...the Prestea Mesothermal Vein Gold Deposit in the Birimian System of Ghana NAPOLEON Q. HAMMOND AND HIDEHIKO...Prestea lode gold deposit occurs in a graphitic shear zone in the Birimian system of Ghana. The Birimian...Proterozoic greenstone assemblage (**« 2100 Ma) with large gold deposits, consisting of a lower unit predominantly | | | Journal (article/letter/editorial) | grained.. Its composition includes quartz, sericite, fuchsite, chlorite, pyrite, pyrrhotite, and more rarely...a mainly quartz-sericite composition. Biotite, fuchsite, microcline and plagioclase occur in smaller quantities;...widely in composition of cement Maximum content of gold' . Up to 1 - 553 g/ton No more than 0.06 ,...Archean granites Staryy Oslcol area Tarkwa gold field (Ghana) after A. I. Bezgubov, 1963 Lower Proterozoicof...Proterozoicof Lower Proterozoic of Tarkwa system Kursk series Archean granites, migma- Gneisses, schists | | Ballo, Ibrahima, Hein, Kim A.A., Guindo, Boukary, Sanogo, Lassana, Ouologuem, Yalema, Daou, Gaoussou, Traore, Amadou (2016) The Syama and Tabakoroni goldfields, Mali. Ore Geology Reviews, 78. 578-585 doi:10.1016/j.oregeorev.2015.10.019 | Journal (article/letter/editorial) | Email: kim.ncube-hein@wits.ac.za MA Abstract Gold deposits in the Syama and Tabakoroni goldfields...the Eburnean orogeny. In TE the Syama goldfield, gold mineralisation in 9 deposits is hosted in the hanging-wall...greywacke, argillite, lamprophyre, and black shale. Gold is currently mined primarily from the oxidised-weathered...quartz-porphyry rocks. AC In the Tabakoroni goldfield, gold mineralisation is hosted in quartz veins in tertiary...amounts of arsenopyrite. There are four main styles of gold mineralisation including silica-sulphide lodes in | | | Journal (article/letter/editorial) | comrlocateroregeorev Lithostratigraphy, geochronology and gold metallogeny in the northern Guiana Shield, South...´ (UQAM Montreal, Quebec, Canada H3C 3P8 b Omai Gold Mines Ltd., 176-D Middle Street, Cummingsburg, PO...improved during the last 20 years, when shallow in situ gold occurrences attracted exploration and mining companies...formed during the Trans-Amazonian orogeny. Most gold deposits and occurrences discovered to date in the...better-explored Precambrian terranes. At a local scale, the gold deposits are hosted within, or in close proximity | | | Report (issue) | Äikäs, R. Sarikkola GHANA The mineralized quartz-pebble conglomerates of Ghana .......................Paleocurrent and lithological faciès control of uranium and gold mineralisation in the Witwatersrand Carbon Leader...J.D. Carter, R.D. Gee Sedimentology, origin and gold potential of the Late Archean Lalla Rookh Basin...thorium-rich resistate minerals, and quartz (and gold if present). Although substantial dissolution and...the amphibolite faciès and are mined mainly for gold. In this report, the preservation of uraninite placers | | | Report (chapter) | temporal patterns of deposit types including orogenic gold, porphyry and epithermal deposits, volcanic hosted...sulphide (VHMS), palaeoplacer Au, iron oxide, copper gold (IOCG), platinum group elements (PGE), diamond and...R e - O s in molybdenite and other sulphides and gold: Stein et al. 1997; Kirk et al. 2001) have allowed...assembly, whereas others (e.g. iron oxide copper-gold; sediment-hosted uranium) formed during intracratonic...Kuroko Palaeoplacer and placer gold P Kiruna - type dl Orogenic gold 1 Ga ~ bh Sediment-hosted | | | Report (issue) | conglomerate Au-U-Os-Ir Diamond placer (and pipes) Placer gold-PGE (high energy) Placer (medium to low energy)...Metal Concentrations Volcanic centers Epithermal gold-silver Mn, Fe, P, (Pb, Ag, Au, Cu) DEPOSIT DESCRIPTION...pyrite and fuchsite. Age Range Major deposits are Archean to L. Proterozoic 3,100-2,200 m.y. Tarkwa is 1900...Associated Deposit Types Recent gold placer deposits. Low-sulfide gold quartz veins and massive sulfide...Concentrations DEPOSIT DESCRIPTION Ore Minerals: Gold, pyrite, uraninite, brannerite, osmium-iridium alloys | | Canet, C., Alfonso, P., Melgarejo, J.-C., Jorge, S. (2003) V-RICH MINERALS IN CONTACT-METAMORPHOSED SILURIAN SEDEX DEPOSITS IN THE POBLET AREA, SOUTHWESTERN CATALONIA, SPAIN. The Canadian Mineralogist, 41 (3) 561-579 doi:10.2113/gscanmin.41.3.561 | Journal (article/letter/editorial) | Ba–F–Pb–Zn–Cu–Ni–Co–Ag veins, as at the Atrevida mine, the largest Ba deposit in the southwestern Catalonian...calc-silicate crystals was reported in the Hemlo gold deposit, Canada (Pan & Fleet 1992). Goldmanite is...in the Pyrenean deposits, chromian muscovite (“fuchsite”) and Ti–Cr oxides are common in some deposits...Bohemia. Veins with roscoelite and barite (with native gold and nickel in the gangue) cut the assemblage. Other...(1989): The mineralogy and geochemistry of the Hemlo gold deposit, Ontario. Geol. Surv. Can., Econ. Geol. | | | Journal (article/letter/editorial) | Orogenic Gold Mineralization from a Deep-Seated Fluid Source at ca 2.65 Ga in the Laverton Gold Province...Western Australia Abstract Many gold deposits in the Laverton greenstone belt, in the northeast of the Eastern...were structural traps controlling the siting of the gold deposits. New regional-scale stable isotope data...resolves this controversy in the Laverton greenstone belt. The median S, C, and O isotope compositions of...minerals from nine different gold deposits in the Laverton greenstone belt fall in a very narrow range | | | Book | Gold Metallogeny and Exploration Edited by R.P. FOSTER Senior Lecturer in Economic Geology Department...the high and continuing demand for gold has prompted a global gold rush on a scale never before seen,...heady days of Ballarat, California and the Yukon. Gold is being sought on every continent and, with very...genetic modelling for the many different types of gold deposits now recognized. This proliferation of data...aspects of gold metallogeny and exploration, ranging from the chemical distribution of gold in the Earth's | | | Journal (article/letter/editorial) | geology of the Prestea goldfield: Gold CoastGeol. Surv.Mm. 3, 20 pp. Gold Coat: 1 dike rock. COOPER, W. G...bauxite deposits of the Gold Coast: Gold Coast Geol. Surv. Bull. 7, 34 pp. Gold Coast: 1 phyllite. COOPER...(1937) The geology of the country around the Jumbo mine, Mazoe district: S. Rhodesia Geol. Surv. Bull. 33... 131 pp. S. Rhode&u: 2; andalusite granulite, fuchsite rock. FOCKEMA, R. A. P. (1950) An occurrence of...t)Iso. ERNEST (1932) Sates on t.hc M’edza platinum mine, Southczrn Rhodesia: Min. Sot. S. Afr. *J. 33, 192 | | Teles, Guilherme S., Chemale, Farid, Ávila, Janaína N., Ireland, Trevor R., Dias, Airton N.C., Cruz, Daniele C.F., Constantino, Carlos J.L. (2020) Textural and geochemical investigation of pyrite in Jacobina Basin, São Francisco Craton, Brazil: Implications for paleoenvironmental conditions and formation of pre-GOE metaconglomerate-hosted Au-(U) deposits. Geochimica et Cosmochimica Acta, 273. 331-353 doi:10.1016/j.gca.2020.01.035 | Journal (article/letter/editorial) | metaconglomerate beds similar to the Witwatersrand gold province. Based on petrographic observations, in... metaconglomerates resemble those found in several pre-GOE gold-bearing metaconglomerates, including detrital and...syngenetic accumulation of gold, as recently proposed for the Witwatersrand gold deposits. 1. INTRODUCTION...in the Jacobina Basin could have influenced the gold accumulation in the metaconglomerate beds. For instance...claimed a syngenetic origin to explain the large gold endowment of the Witwatersrand Basin (e.g., Horscroft | | | Journal (article/letter/editorial) | Jacobina Range is composed of an Archean greenstone belt, Au-U detrital pyrite-bearing sedimentary rocks...the Archean evolution of the Mundo Novo Greenstone Belt and the subsequent deposition of sediments in the...Jacobina Basin; Mundo Novo Greenstone Belt; Transpressional Fold Belt; São Francisco Craton 2 1 Introduction...region contains emerald, manganese, chromium and gold mineralization, including Au (U)-bearing mineralization...the northern portion of the Mundo Novo greenstone belt, the N-S mafic-ultramafic sills and dikes, and the | | | Book | staurolite porphyroblasts in stt-and-schist; Nauyago, Ghana. d) Colour zonation in titanaugite phenocryst in...Chloritoid (length-fast), in chloritoid phyllite; Tarkwa, Ghana; b) Andalusite (length-fast) in andalusite slate;...calcareous semipelitic schist; Mangkuma-Ketempe, Ghana. x100 80 TREMOLITE(◻) x100 38 A Key for Identification...Chloritoid (end-section) in chloritoid phyllite; Tarkwa, Ghana. 84 x50 40 13 A Key for Identification...DOLOMITE XPL (1k) Dolomite in chl-talc-dol schist; Ghana 92 (Note: Magnesite (of serpentinites) is optically | | | Journal (issue) | Chalcedony from Peru • Afghan emerald mining • Fuchsite-rich rock • Color-change garnet from Tanzania...1994 (Thang, 1998). In 1996 the Vietnam National Gold and Gem Corporation (VIGEGO) conducted systematic...operation (figure 3) belongs to DOJI Gold & Gems Group Figure 3. DOJI Gold & Gems Group currently conducts...belong to the State Treasury’s collection, while DOJI Gold & Gems Group has preserved an 18.8 kg specimen (figure...gems mined at Tan Huong–Truc Lau, belongs to DOJI Gold & Gems Group. The stone measures approximately 32 | | | Report (issue) | Supergroup in South Africa that contains Earth’s largest gold-uranium deposits. These deposits are hosted by quartz-pebble...paper, Minter shows that the sedimentary setting of gold, pyrite, and uraninite favors a detrital origin...geologic and geochemical features indicating that the gold, uranium, and sulfur were deposited by hydrothermal...conglomerates that host only uraninite and pyrite, but no gold. In the final paper, Gauthier-Lafaye shows that................105 W.E.L. Minter 7. Witwatersrand gold-pyrite-uraninite deposits do not support a reducing | | | Book (edition) | Average Hardness Soft minerals, such as galena or gold, are very difficult to polish without any scratches;...certain degree of bending, while some metals, such as gold, may be deformed into very thin sheets. The term...pyrite, and irregular late stage pore-fillings of gold (yellow). Right: Finely laminated iron oolith with...Mineral lamellar faint, red yes brown bright green gold-yellow, silver-white (Ag) to copper-red (Cu); 72...bluish tint; 55.12 Internal Twinning Reflect. Gold, native Polarite yes Nickelskutterudite yes | | | Conference Proceedings (Volume) | Cover photograph: View of the Aitik open pit copper mine in the very north of Sweden. Mining operations started...copper, 51 700 tonnes of silver and 1,9 tonnes of gold. Photo: Olof Martinsson, Luleå University of Technology...ultramafic intrusive complex, McFaulds Lake greenstone belt, Ontario .........................................sulphide lenses at the Delta deposit, Cape Smith Belt, Canada: implication for the distribution of PGE...Norman Pearson, Jan Kramers & Dmitry Kuzmin Orogenic gold deposits .. ................................... | | | Book | reasons for the approach taken Mineral deposit or mine? A genetic model as the basis for exploration The...hydrothermal gold deposits Hydrothermal gold deposits in Archaean terrain Exploration for gold in Archaean...Exploration for porphyry molybdenum deposits Porphyry gold deposits Porphyry tin deposits Volcanic-associated...Council, BP Minerals International, Consolidated Gold Fields PLC, Gencor (UK) Ltd and RTZ Services Ltd...many geologists who have given their time during mine visits and responded to our queries. We have benefited | | Hodges, C.A., Cox, D.P., Singer, D.A., Case, J.E., Berger, B.R., Albers, J.P. (1984) U.S. Geological Survey-INGEOMINAS mineral resource assessment of Colombia. Open-File Report Vol. 1984 (84-345) US Geological Survey doi:10.3133/ofr84345 | Report (issue) | chromite (1.1) 7 Porphyry copper molybdenum-rich; gold-rich (2.1, 2.2) 9 Molybdenum porphyry climax type;...deposits (4.8) 28 Epithermal gold, quartz-adularia type (5.4) 30 Hot springs gold-silver deposits (5.6) ...deposits 27 13. Epithermal gold, quartz-adularia type 29 14. Hot springs gold-silver deposits 31 ii...mineral deposit types. In addition to new deposits of gold, silver, and platinum group elements, significant...possibilities for the occurrence of bauxite, iron, uranium, gold, diamonds, rare earths, possibly tin and tungsten; | | | Report (volume) | success. An example might be the seeking of additional gold nuggets in a stream in which one nugget had already...U-Au, by Dan L. Mosier 249 Descriptive model of gold on flat faults, by Bruce A. Bouley 251 248 Deposits...Tonnages of komatiitic Ni-Cu deposits 20 Nickel and gold grades of komatiitic Ni-Cu deposits 21 PGE grades...grades of polymetallic replacement deposits 104 Gold grades of polymetallic replacement deposits 104...112 Copper grades Qf porphyry Cu-Au deposits 112 Gold grades of porphyry Cu-Au deposits 113 By-product | | | Journal (article/letter/editorial) | . . . . . . . . . . . . . . . . . . . . . . . . Gold. . . . . . . . . . . . . . . . . . . . . . . . ...and mineralogy of gold . . . . . . . . . . . . . . . . . . . . . . . 20.2. Magmatic gold deposits . . .... Structure-bound gold deposits . . . . . . . . . . . . . . . 20.4. Sedimentary gold deposits . . . .... . 20.5. Metamorphic gold deposits . . . . . . . . . . . . . . . . . 20.6. Gold supply and use . . ....Franckeite Francolite Franklinite Freibergite Fuchsite (chromium muscovite) Gahnite Galena Galkhaite |
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