 | | Journal (article/letter/editorial) | | PGM grains associated with the Freetown Layered Complex, Sierra Leone, and their origin Keiko Hattori...(residual) origin, associated with the Freetown Layered Gabbro Complex, were determined in-situ using an ion...systematic mineralogical and chemical changes of the Complex and extensive granulitization in the adjacent host...1988). The P G M grains in Sierra Leone occur in laterites covering a layered ultramafic intrusion and...without surface abrasion. The tropical climate in the area was proposed to be conducive to the formation of |  | Bowles, J. F. W., Lyon, I. C., Saxton, J. M., Vaughan, D. J. (2000) The Origin of Platinum Group Minerals from the FreetownIntrusion, Sierra Leone, Inferred from Osmium Isotope Systematics. Economic Geology, 95 (3) 539-548 doi:10.2113/gsecongeo.95.3.539 | Journal (article/letter/editorial) | | of Platinum Group Minerals from the Freetown Intrusion, Sierra Leone, Inferred from Osmium Isotope Systematics...isotope ratios in PGM grains from the Freetown peninsula in Sierra Leone using an ion microprobe. Indirect...alluvial PGM grains that have been studied, the Freetown ones are distinguished by 187Os/188Os ratios that...Introduction THE EXPOSED part of the Freetown layered intrusion, Sierra Leone, is crescent shaped and occupies...intrusion. Later raised beach deposits occur along the western edge (Gregory, 1962). Weathering of the intrusion |  | | Journal (article/letter/editorial) | | vysotskite and keithconnite from the Freetown Layered Complex, Sierra Leone J. F. W. Bowles Mineral Science...1999 Summary The Pt-Fe nuggets of the Freetown Intrusion, Sierra Leone contain many included platinum-group...Frequently these are Os-Ir alloys or members of the laurite-erlichmanite series. An inclusion described here...aus dem Freetown Komplex, Sierra Leone 76 J. F. W. Bowles Die Pt-Fe-Nuggets der Freetown-Intrusion...Freetown-Intrusion, Sierra Leone enthalten eine Vielzahl von Platingruppenmineralen (PGM) als EinschluÈsse. Hier handelt |  | | Journal (article/letter/editorial) | | isoferroplatinum nugget from the Freetown Layered Complex, Sierra Leone. John F.W. Bowles1, Saioa Suárez2...isoferroplatinum nuggets from the Freetown Peninsula, Sierra Leone, are aligned with their shape determined...observed in other nuggets from the same area. The inclusions contain laurite (RuS2), irarsite-hollingworthite...alloy. PGM found on the nugget surface include laurite, irarsite and cuprorhodsite (CuRh2S4). The Pd-Te-Bi-Sb...starting intergrowths of laurite and irarsitehollingworthite with both laurite and irarsite-hollingworthite |  | | Journal (article/letter/editorial) | | platinum-group minerals of the Freetown Layered Complex, Sierra Leone. 1 John F.W. Bowles1, Saioa Suárez2...rivers and river terraces near York, Freetown Peninsula, Sierra Leone have been examined for their platinum-group...hongshiite (PtCu), cooperite–vysotskite (PtS–PdS), laurite (RuS2), erlichmanite (OsS2), Os-Ir alloy, Os-Ru...primary and placer PGM support the proposal that the Freetown nuggets developed as a result of breakdown of...Keywords: Platinum-group minerals • Freetown Intrusion, Sierra Leone • Alluvial • Nuggets Introduction |  | Augé, Thierry, Gloaguen, Éric, Chevillard, Matthieu, Bailly, Laurent (2018) Mineralogy, geochemistry and emplacement of the Conakry Igneous Complex, Guinea: implications for the Ni–Cu–PGE mineralization. Mineralogical Magazine, 82 (3) 593-624 doi:10.1180/mgm.2018.79 | Journal (article/letter/editorial) | | geochemistry, and emplacement of the Conakry Igneous Complex, Guinea: implications for the Ni-Cu-(PGE) mineralization...1180/mgm.2018.79. Abstract The Conakry Igneous Complex (CIC) is a mafic-ultramafic intrusion emplaced...contemporaneously with the opening of the Atlantic, forming a complex, 55 x 5 km dyke-like body within which three main...sulfides (BMS) are present in all units of the complex and earlier descriptions have mentioned a “massive...composite Ni-Fe-Cu sulfides. Most PGM grains form complex associations resulting either from exsolution or |  | Bowles, J. F. W., Prichard, H. M., Suarez, S., Fisher, P. C. (2013) THE FIRST REPORT OF PLATINUM-GROUP MINERALS IN MAGNETITE-BEARING GABBRO, FREETOWN LAYERED COMPLEX, SIERRA LEONE: OCCURRENCES AND GENESIS. The Canadian Mineralogist, 51 (3) 455-473 doi:10.3749/canmin.51.3.455 | Journal (article/letter/editorial) | | MINERALS IN MAGNETITE-BEARING GABBRO, FREETOWN LAYERED COMPLEX, SIERRA LEONE: OCCURRENCES AND GENESIS John F...magnetite-bearing gabbroic rocks of the Freetown Layered Complex, Sierra Leone for the first time. The PGM occurrences...Bowieite [(Pt,Ir,Rh)2S3], tulameenite (Pt2CuFe), and laurite (RuS2) have also been found in this horizon. Cooperite...alluvial PGM of the Freetown complex, which are predominantly Pt-Fe alloys, laurite, erlichmanite (OsS2)...has yet been discovered. Previous studies of this area have suggested that secondary remobilization of |  | | Journal (article/letter/editorial) | | sulfides and Pt–Fe alloys in the Freetown Layered Complex, Sierra Leone John F. W. Bowles 1 & Saioa Suárez...rocks and saprolite from Horizon B of the Freetown Layered Complex contain platinum-group minerals (PGM)...tetraferroplatinum (PtFe), tulameenite (Pt2FeCu), Os-bearing laurite (RuS2), and other base metalsulfide (BMS)-bearing...Keywords Platinum-group minerals . Freetown intrusion . Sierra Leone . Weathering . Mobility of platinum...and alluvial deposits from the Freetown Layered Intrusion in Sierra Leone, West Africa, since 1926 and |  | | Journal (article/letter/editorial) | | tS7Os/lS6Os ratios were determined for in-situ laurite grains in Alpine-type chromitites and platinumgroup...Borneo, Indonesia/Malaysia. The Osisotope ratios of laurite grains in chromite d e f n e an t87Os/186Os ratio...minerals, laurite, chromitites, Borneo, Indonesia, Malaysia. Introduction Geology of the area THE 1870S/186Os...ratios of insitu laurite in chromitites of an Alpine-type ultramafic-mafic complex and of PGM from the...Cretaceous crystalline schists. The rocks in the area are highly deformed and segments of different lithologies |  | Prichard, Hazel M., Suárez, Saioa, Fisher, Peter C., Knight, Robert D., Watson, John S. (2018) Placer platinum-group minerals in the Shetland ophiolite complex derived from anomalously enriched podiform chromitites. Mineralogical Magazine, 82 (3) 491-514 doi:10.1180/minmag.2017.081.099 | Journal (article/letter/editorial) | | PLATINUM-GROUP MINERALS IN THE SHETLAND OPHIOLITE COMPLEX DERIVED FROM ANOMALOUSLY ENRICHED PODIFORM CHROMITITES...Harold's Grave localities in the Shetland ophiolite complex have been well documented previously. The focus...minor Pd-sulfides, Pt-Pd-Cu and Pt-Fe alloys, and laurite. Gold also occurs with the PGM. Alluvial PGM have...absent. At Harold's Grave only 3 alluvial PGM (laurite, Ir, Os) and Au were recovered reflecting the limited...surficial conditions. Keywords: Shetland ophiolite complex, Cliff, Harold's Grave, alluvial concentrates, |  | | Journal (article/letter/editorial) | | Oxidized Ores into Placers: Case Studies Bushveld Complex, South Africa, and Great Dyke, Zimbabwe Thomas...(PGM) in the weathering cycle in the Bushveld Complex of South Africa and the Great Dyke of Zimbabwe...world’s prime sources of platinum-group (PGE) are layered intrusions of Proterozoic crystallites, or rarely...detrital/allogenic PGM and Archean age (e.g., Bushveld Complex, South Africa; the Great Dyke, Zimbabwe; the Stillwater...In the Bushveld/Great Dyke scenario, and in all Complex, USA). Placer deposits in Russia and in Colombia |  | | Journal (article/letter/editorial) | | platinum-iron alloy placer grains from the Freetown layered complex; Sierra Leone J. L. C. Stewart I. C. Lyon D....of the USA and Canada, in Kalimantan, and in Sierra Leone, osmium isotopes have provided useful insights...associated with the Freetown igneous complex, Sierra Leone, is being investigated. The Freetown intrusion is...anorthosite, four of which are exposed on the Freetown Peninsula and the fifth seen only in a borehole...zones forming four arcuate ranges of hills on the Freetown Peninsula. The PGM grains are found in soils, |  | | Journal (article/letter/editorial) | | platinum-group element minerals (PGM) occur as laurite (RuS2), erlichmanite (OsS2), irarsite (IrAsS) and...and in laterites related with the Freetown layered gabbro, Sierra Leone and many other deposits worldwide...Sulfides of the iridium group PGE (IPGE) such as laurite (RuS2), erlichmanite (OsS2) and irarsite (IrAsS)...al., 2005). Alluvial PGM from the Freetown intrusion, Sierra Leone have been described by Bowles (1986)...and forms large (0.5–7 mm) irregular grains. Laurite–erlichmanite and osmium–iridium alloy occur both |  | Zaccarini, Federica, Bindi, Luca, Pushkarev, Evgeny, Garuti, Giorgio, Bakker, Ronald J. (2016) Multi-Analytical Characterization of Minerals of the Bowieite–Kashinite Series From the Svetly Bor Complex, Urals, Russia, and Comparison With Worldwide Occurrences. The Canadian Mineralogist, 54 (2) 461-473 doi:10.3749/canmin.1500021 | Journal (article/letter/editorial) | | BOWIEITE– KASHINITE SERIES FROM THE SVETLY BOR COMPLEX, URALS, RUSSIA, AND COMPARISON WITH WORLDWIDE OCCURRENCES...ultramafic rocks associated with the Gusevogorskiy Complex in the Urals. Cabri et al. (1981) reported on the...the concentrically zoned mafic-ultramafic Gaosital Complex in China. This Rh2S3 phase, however, was officially...magnetite-bearing gabbros from the Freetown Layered Complex of Sierra Leone (Bowles et al. 2013). Kashinite...(1985) from the Niznhy Tagil Ural-Alaskan type Complex, located in the central Urals of Russia. It was |  | Barkov, A. Y., Fleet, M. E., Martin, R. F., Halkoaho, T. A.A. (2005) New data on "Bonanza"-type PGE mineralization in the Kirakkajuppura PGE deposit, Penikat layered complex, Finland. The Canadian Mineralogist, 43 (5) 1663-1686 doi:10.2113/gscanmin.43.5.1663 | Journal (article/letter/editorial) | | IN THE KIRAKKAJUPPURA PGE DEPOSIT, PENIKAT LAYERED COMPLEX, FINLAND ANDREI Y. BARKOV§ AND MICHAEL E. FLEET...FLEET Department of Earth Sciences, University of Western Ontario, London, Ontario N6A 5B7, Canada ROBERT...species occur in the Kirakkajuppura area, Penikat layered complex, Finland. The PGM are intimately associated...unusual micro-aggregates), laflammeite [Pd3Pb2S2], laurite–erlichmanite series [(Ru,Os,Ir)(S,As)2 – (Os,Ru...is located near the northern end of the Penikat complex. Keywords: platinum-group elements, platinum-group | | | Journal (article/letter/editorial) | | hydrothermal alteration of carbonatite in the Fen Complex, Norway: mineralogy, geochemistry, and implications...(Marien et al., 2018). In the Fen carbonatite Complex up to 1.6 wt.% total REE occurs in hydrothermally...horizons from the Transdanubian Mountain Range (western Hungary): genetic implications’. Uranium and REE...platinum-group minerals of the Freetown Layered Complex, Sierra Leone’ (Bowles et al., 2018). Large alluvial...alluvial PGMcontaining Pt-Fe-Cu alloys, laurite-erlichmanite and Os-Ir-Ru alloys differ from the mineral |  | | Journal (article/letter/editorial) | | Pt) is present in complex assemblages in Kraubath, usually intergrown with laurite, Pt-Fe alloy and Rh...(Ni,Cu,Fe,Ir,Rh,Os) sul®des are intergrown with laurite-erlichmanite, Ir-Os alloy, and rarely, PGE sulfarsenides...massif of Kraubath (Austria) is part of the Speik Complex of the Austroalpine crystalline basement nappes...deformed, metamorphosed and dismembered ophiolite complex (Stump¯ and El Ageed, 1981). Ultrama®c rocks (harzburgite...± 39% Os-Ir-Ru (BM) alloy 23% Pt-Fe alloy ± Laurite ± erlichmanite 42% Ir-Rh sul®de 3% BM-PGE sul®de |  | Wilhelm, H. J., Zhang, H., Chen, F. L., Elsenbroek, J. H., Lombard, M., de Bruin, D. (1997) Geochemical exploration for platinum-group elements in the Bushveld Complex, South Africa. Mineralium Deposita, 32 (4) 349-361 doi:10.1007/s001260050101 | Journal (article/letter/editorial) | | exploration for platinum-group elements in the Bushveld Complex, South Africa Received: 31 May 1996 / Accepted:...stream sediment and soil samples from the Bushveld Complex, South Africa have revealed enhanced precious metal...hosted by the Upper Critical Zone of the Rustenburg Layered Suite are revealed by a high PGE and Au content...follows the igneous layering of the Rustenburg Layered Suite and is oset by the Brits Graben. It is therefore...Rustenburg Layered Suite of the Bushveld Complex comprises the world's largest ma®c-ultrama®c layered intrusion |  | | Journal (article/letter/editorial) | | minerals Article Zoned Laurite from the Merensky Reef, Bushveld Complex, South Africa: “Hydrothermal”...Published: 21 April 2020 Abstract: Laurite, ideally (Ru,Os)S2 , is a common accessory mineral...the occurrence of zoned laurite found in the Merensky Reef of the Bushveld layered intrusion, South Africa...Africa. The zoned laurite forms relatively large crystals of up to more than 100 µm, and occurs in contact...zoned crystals of laurite show a slight enrichment in Os in the rim, as typical of laurite that crystallized |  | Slansky, E., Barron, L. M., Suppel, D., Johan, Z., Ohnenstetter, M. (1991) Platinum mineralization in the Alaskan-type intrusive complexes near Fifield, N.S.W., Australia. Part 2. Platinum-group minerals in placer deposits at Fifield. Mineralogy and Petrology, 43 (3) 161-180 doi:10.1007/bf01166889 | Journal (article/letter/editorial) | | furnished the largest quantity of platinum from the area. PGM nuggets were collected in a corridor, south...isoferroplatinum, native osmium, osmiridium, iridosmine, laurite and bowieite. Isoferroplatinum is the matrix mineral...inclusions of euhedral chromite. Two sulphidic phases--laurite and bowieite--are rare and occur embedded as trapped...in Placer Deposits at Fifield 163 toOWENDALE complex ~ad e ~P 6 ~ 1km Iotin I Fig. 1. Sketch map...distance from Fifield to the Owendale intrusive complex with hard rock PGE mineralization (Johanet al. |  | Airiyants, Evgeniya V., Belyanin, Dmitriy K., Zhmodik, Sergei M., Agafonov, Leonid V., Romashkin, Pavel A. (2020) Chemical composition and origin of platinum-group minerals from placers of the Aunik River, Buryatia, Russia. Ore Geology Reviews, 120. 103453 doi:10.1016/j.oregeorev.2020.103453 | Journal (article/letter/editorial) | | studied. The present study of PGM grains reveals complex relationships between the mineral phases within...cuproiridsite, iridisite, malanite, cooperite, laurite, erlichmanite and tolovkite. These two types of...available on the distribution and origin of PGM in western Transbaikalia, and specifically, in the Bauntovsky...generalized overview of the distribution of the PGMs in Western Transbaikalia. Placer mineralization has been briefly...meta-gabbro, which together form the Shamansky ophiolite complex (Fig. 2). In the absence of systematic mineralogical |  | Prichard, Hazel M., Mondal, Sisir K., Mukherjee, Ria, Fisher, Peter C., Giles, Nicolas (2018) Geochemistry and mineralogy of Pd in the magnetitite layer within the upper gabbro of the Mesoarchean Nuasahi Massif (Orissa, India) Mineralium Deposita, 53 (4) 547-564 doi:10.1007/s00126-017-0754-4 | Journal (article/letter/editorial) | | layer occurs at a high stratigraphic level in the complex and is nearly 4-km long and 5–12-m thick. The sections...other PGM including PtAs2 (sperrylite), RuS2 (laurite), and IrRhAsS Editorial handling: M. Fiorentini...Pd-oxides. The Nuasahi Massif is a sill-like Archean layered ultramafic-mafic intrusion genetically linked to... Magnetitite . Chromitite . Sill-like layered igneous complex . Upper gabbro unit . Nuasahi Massif Introduction...parts of layered complexes worldwide. Some of the more well-known ones include the Bushveld Complex (Barnes |  | Airiyants, Evgenia V., Kiseleva, Olga N., Zhmodik, Sergey M., Belyanin, Dmitriy K., Ochirov, Yuriy C. (2021) Platinum-Group Minerals in the Placer of the Kitoy River, East Sayan, Russia. Minerals, 12 (1) 21 doi:10.3390/min12010021 | Journal (article/letter/editorial) | | the southern plate of the Ospa-Kitoy ophiolite complex, and primarily chromitites. min12010021 Academic...complexes of Tuva [20], Western Sayan (Kalna ultrabasic massif [21], Aktovrakskiy complex [22–24]), and Eastern...previous studies. 2. Geological Setting The study area is the southeastern part of the Eastern Sayan (SEPES)—a...during the Neoproterozoic-Early Paleozoic. In this area, there is a multistage tectonics and tectonomagmatic...Previous researchers have obtained data on the complex structure and heterogeneity of these ophiolite |  | Stanley, C. J., Criddle, A. J., Spratt, J., Roberts, A. C., Szymański, J. T., Welch, M. D. (2005) Kingstonite, (Rh,Ir,Pt)3S4, a new mineral species from Yubdo, Ethiopia. Mineralogical Magazine, 69 (4) 447-453 doi:10.1180/0026461056940262 | Journal (article/letter/editorial) | | alloy, osmium, enriched oxide remnants of osmium, laurite, bowieite, ferrorhodsite and cuprorhodsite. It...osmium, enriched oxide remnants of osmium and laurite. Kingstonite is opaque with a metallic lustre and...Ethiopia, occur over an area of ~30 km 2 within an overall prospecting area of >500 km . In addition...dunite and pyroxenites of the Yubdo ultrama®c complex (Mogessie et al., 1999). The mineralogy of the...image in oil of kingstonite in association with laurite and ferrorhodsite in an isoferroplatinum matrix |  | Lyon, I. C., Tamana, H., Vaughan, D. J., Criddle, A. J., Saxton, J. M., van Lierde, P. (1997) Techniques and methodology used in a mineralogical and osmium isotope study of platinum group minerals from alluvial deposits in Colombia, California, Oregon and Alaska. Mineralogical Magazine, 61 (406) 367-375 doi:10.1180/minmag.1997.061.406.04 | Journal (article/letter/editorial) | | inclusions of other PGM such as cooperite and laurite. Detailed analyses were undertaken on the O s -...mechanically concentrated and dredged placer-PGM from the western seaboard of North America. This collection is now...grains include sperrylite, cooperite, irarsite and laurite. Gold is a minor constituent of the finer fractions...remainder include grains of sperrylite, irarsite, laurite, ruarsite, gold and various PGE-bearing pentlandites...and various other spinels. These, and some gold, laurite and erlichmanite grains were mounted in epoxy resin |
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