 | | Journal (article/letter/editorial) | | in ultramafic complexes at western Andriamena, Madagascar I. McDonald* Small (,2 km diameter), ultramafic...intrusive complexes in the Andriamena region of Madagascar carry high concentrations of platinum-group elements...liquid–olivine–sulphide liquid into the dyke-like Lavatrafo intrusions. The high As content of the sulphide...Arsenides, Ultramafic complexes, Andriamena, Madagascar Introduction Geochemical exploration carried...uk complexes near Lavatrafo in the west Andriamena region of northern Madagascar (Fig. 1) contain high |  | | Journal (article/letter/editorial) | | at the Ranomena mine, Toamasina chromite district, Madagascar Giovanni Grieco ⁎, Anna Merlini, Alberto...group elements Platinum group minerals Chromitite Madagascar a b s t r a c t This paper presents new data...mine in the North Toamasina chromite district of Eastern Madagascar. Such data can provide an insight on...the differences with other chromite deposits of Madagascar. Chromitite host rocks are harzburgite and pyroxenite...Elsevier B.V. All rights reserved. 1. Introduction Madagascar has never been a platinum-group-element (PGE) |  | McDonald, I., Ohnenstetter, D., Ohnenstetter, M., Vaughan, D. J. (1999) Palladium oxides in ultramafic complexes near Lavatrafo, Western Andriamena,
Madagascar. Mineralogical Magazine, 63 (3) 345-352 doi:10.1180/002646199548565 | Journal (article/letter/editorial) | | in ultramafic complexes near Lavatrafo, Western Andriamena, Madagascar ]L. MCDONALD 1" , D. OHNENSTETTER...intrusive complexes in the Andriamena region of Madagascar contain zones with disseminated chromite and...palladium, oxygen, hydrated oxides, Andriamena, Madagascar. Introduction GEOCHEMICALexploration carried...mafic intrusive complexes near Lavatrafo in the Andriamena region of Madagascar (Fig. 1) contain high concentrations...and drilling have shown that dunites within the Lavatrafo UM2 and UM3 ultramafic complexes defined by Salp6teur |  | | Journal (article/letter/editorial) | | (pyrrhotite and pyrite), Cu (chalcopyrite) and Ni (pentlandite) and are present mostly as small, discrete PGE...associated base-metal sulphides—particularly pentlandite— can also carry appreciable PGE contents in solid... Unpublished electronmicroprobe analyses of pentlandite by the author support the contention of Oberthür...dominantly in the form of solid solution in pentlandite throughout the profile. Summary In all the foregoing...significant proportion of Pd and Rh is hosted in pentlandite.14,33 The primary mineralization is characteristically |  | | Journal (article/letter/editorial) | | predominant PGM associated with pyrrhotite and pentlandite in MSS ores. In addition, the PGM in chalcopyrite-rich...result of their enclosure within chalcopyrite and pentlandite. Keywords: platinum-group minerals, Raglan deposits...prédominants en association avec la pyrrhotite et la pentlandite dans les minerais massifs (MSS). De plus, les...présents en inclusions dans la chalcopyrite et la pentlandite. (Traduit par la Rédaction) Mots-clés: minéraux...section is made up predominantly of pyrrhotite and pentlandite, with some chalcopyrite, magnetite, carbonate |  | | Journal (article/letter/editorial) | | originally hosted by sulphide mineral phases (e.g., pentlandite). This element was immobile in all other Modderfontein...Great Dyke (Coghill and Wilson 1993), Lavatrafo AC Complex, Madagascar (McDonald 2008) and Sudbury (Dare...accommodated in both PGM and solid solution in pentlandite (Godel et al. 2007, Osbahr et al. 2013, Junge...Removal of sulphides during alteration, and pentlandite in particular, may potentially liberate ACCEPTED...intrusions is hosted by base-metal sulphides such as pentlandite (Godel et al. 2007, Holwell and McDonald 2007 |  | | Journal (article/letter/editorial) | | Since the 1930s, plutons of the Monchegorsk ore district have been regarded as nickel-bearing. The first...Paleoproterozoic layered plutons of the Monchegorsk ore district were discovered in the late 1990s. As Corresponding...of the Monchegorsk pluton in the area of the Pentlandite Canyon became regarded as promising for PGE ores...in intercumulus Cr-spinel in association with pentlandite, heazlewoodite, accessory galena and native copper...formation of zonal grains (Fig. 2a). Pyrrhotite, pentlandite, chalcopyrite, and magnetite are the major ore |  | | Journal (article/letter/editorial) | | silicate stratigraphy (Barnes et al., 2011). Pentlandite is the dominant sulphide phase present in the...included a small bleb of pentlandite adjacent to a larger crystal of pentlandite (Fig. 5E). As in the Santa...observed. On one occasion magnetite is present with pentlandite in a vein of serpentine (Fig. 5F). This dunite...characterising a thick layer of disseminated sulphides (pentlandite, chalcopyrite, pyrrhotite and pyrite). This zone...pyrite is observed to be intergrown with pentlandite. Pentlandite (¡intergrown pyrite) tends to form the |  | | Journal (article/letter/editorial) | | described from chromites in the Andriamena region of Madagascar by Ohnenstetter et al. (1999) and McDonald et...a hexagonal inclusion of pyrrhotite (po) and pentlandite (pn) within chromite (chr), surrounded by altered...(plag). b hexagonal inclusion of chalcopyrite, pentlandite and pyrrhotite and a small inclusion of chalcopyrite...inclusion made up of chalcopyrite, pyrrhotite, pentlandite and a small micron-sized grain of the PGM moncheite...polyphase inclusion made up of chalcopyrite, pentlandite, pyrite (py) and the PGMs laurite (lau) and sperrylite |  | | Journal (article/letter/editorial) | | variable proportions of Pd and Rh are hosted in pentlandite. Pt–Fe alloys, sperrylite, and most PGE-sulfides...Bushveld Complex in South Africa, of the Sudbury district in Canada, and later Norilsk in Russia grand style...Bushveld Complex in South Africa, of the Sudbury district in Canada, and later Norilsk in Russia came into...Bushveld Complex in Southfrom Africa, of the Sudbury district in Canada, The 2054.4 [1–3]. ± 1.3-Ma-old [9]...to sulfide accumulations (mainly pyrrhotite, pentlandite, chalcopyrite, and sporadic pyrite), in a manner |  | Kozlu, Hatice, Prichard, Hazel, Melcher, Frank, Fisher, Peter, Brough, Christopher, Stueben, Doris (2014) Platinum group element (PGE) mineralisation and chromite geochemistry in the Berit ophiolite (Elbistan/Kahramanmaraş), SE Turkey. Ore Geology Reviews, 60. 97-111 doi:10.1016/j.oregeorev.2013.12.011 | Journal (article/letter/editorial) | | sulphides, which are, in order of abundance, pentlandite, chalcopyrite, bornite and pyrrhotite. 6. Composition...Subhedral laurite grains are often associated with pentlandite, heazlewoodite or millerite both in the harzburgite...irarsite and hollingworthite partially enclosed by pentlandite on the edge of chromite that is adjacent to a...(MBAC-10A). They usually contain chalcopyrite and pentlandite, though these may also be altered to bornite...grain was detected in association with BMS (pentlandite and chalcopyrite, analysis BM-2 and BM-3 in MBD-7 |  | Mota-E-Silva, Jonas, Prichard, Hazel M., Suárez, Saioa, Ferreira Filho, Cesar F., Fisher, Peter C. (2016) Supergene Alteration of Platinum-Group Minerals and the Formation of Pd-Cu-O and Pd-I-O Compounds In the Limoeiro Ni-Cu-(PGE) Deposit, Brazil. The Canadian Mineralogist, 54 (3) 755-778 doi:10.3749/canmin.1500049 | Journal (article/letter/editorial) | | smaller equal proportions of chalcopyrite and pentlandite and minor PGM are typical of the fresh ore assemblage...apparent as deep as ~50 m with the oxidation of pentlandite and pyrrhotite to produce violarite and pyrite...altered and oxidized (Fig. 5A). At this depth pentlandite is altered to violarite, which is oxidized, and...uncertainties on the depth of alteration of pentlandite and pyrrhotite to violarite and pyrite. Mineral...orthopyroxene (Opx), amphibole (Amp), chromite (Chr), pentlandite (Pn), pyrrhotite (Po), chalcopyrite (Cp), merenskyite |  | Suárez, Saioa, Prichard, Hazel M., Velasco, Francisco, Fisher, Peter C., McDonald, Iain (2010) Alteration of platinum-group minerals and dispersion of platinum-group elements during progressive weathering of the Aguablanca Ni–Cu deposit, SW Spain. Mineralium Deposita, 45 (4) 331-350 doi:10.1007/s00126-009-0275-x | Journal (article/letter/editorial) | | Mineralisation is mainly composed of pyrrhotite, pentlandite, chalcopyrite and pyrite with minor marcasite...mineralisation is dominated by pyrrhotite and pentlandite and is limited to the central core of the southern...composed mainly of pyrrhotite, chalcopyrite and pentlandite and (c) irregular ore with variable sulphides...metal sulphides, notably with pyrrhotite and pentlandite, less chalcopyrite and occasionally pyrite. A...pyrite, with minor strongly altered pyrrhotite (±pentlandite) and chalcopyrite. Malachite, chalcocite, covellite |  | | Journal (article/letter/editorial) | | partly coated by tulameenite (1) with intergrown pentlandite (2). AS6392/101. b) Pt–Fe alloy rimmed by Pt(Fe...stibiopalladinite, rustenburgite, Au–Ag alloy, laurite and pentlandite (Fig. 3a) in the [Pt(Fe,Cu)] rim phase. Hollingworthite...shallow levels of an ultramafic intrusion in Madagascar (McDonald et al. 1999a). Pd–O–H phases with a...Pt–Fe nuggets from alluvial deposits in eastern Madagascar. Can. Mineral. 30, 983-1004. ________ & ________...in ultramafic complexes near Lavatrafo, western Andriamena, Madagascar. Mineral. Mag. 63, 345-352. ________ |  | | Journal (article/letter/editorial) | | Country Ethiopia USA USA Colombia Madagascar N. Caledonia Madagascar N. Caledonia Ethiopia USA N. Caledonia...Sulphides Sulphides such as pyrite, chalcopyrite, pentlandite are present but rare. Oxides Pt-Ir-(Os)-K-Cl...Pt-Fe nuggets from alluvial deposits in eastern Madagascar. The Canadian Mineralogist, 30, 983 1004. Augé...concentrates of the AntanambaoManampotsy area, Madagascar. Comptes-rendus de l’Académie des Sciences de...oxides in ultramafic complexes near Lavatrafo, Western Andriamana, Madagascar. Mineralogical Magazine, 63, 345 |  | | Book | | inclusions such as PGE-rich monosulfide, PGE-rich pentlandite, and Ni–Fe–(As)-rich laurite. The authors suggested...thiospinels and monosulfides; Ru-Pentlandite (NiFeRu)9 S8 , Rh-Pentlandite (NiFeRh)9 S8 , Pt-pyrrhotite (FePt)1−x...containing detectable amounts of PGE (mainly Ru-pentlandite) (Figure 3B), which may be found in both primary...Isoferroplatinum in contact with erlichmanite, pentlandite, and clinopyroxene. (E) Bi-phase grain of isoferroplatinum...Cpx = clinopyroxene, Cpr = cuprorhodsite, Pn = pentlandite, Tfp = tetraferroplatinum, PtFe = Pt–Fe alloy |  | | Book | | Japan, 462 Switzerland, 510 Tanzania 463 Madagascar (Malagasy Republic), Malawi Nepal, 482 513...more km) from Coptos passed center for these district, correspond cites a King to the are to Bostock...location of the mines Holland’s translation, of district, and it could have been Probably these mines...BERYL IN 44 in the material carved in China, Madagascar Pough, beryl is is in existence.” morganite...London contains the finest and largest pink Madagascar faceted morganite known did hundreds of small |
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