Fluid and metal sources in the Fäboliden hypozonal orogenic gold
The field observations of the ductile fabric (shearing) that passes from the metagreywacke into the granite, together with the relationship between the different geothermometers, suggests that the gold mineralization at Fäboliden is considered post-peak metamorphic and contemporaneous with the emplacement of the 1.80–1.77 Ga …
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The Pampe gold deposit (Ghana): Constraints on sulfide …
The Ashanti belt, a world-renowned gold producing region in southwest Ghana, has received renewed attention in recent years. Most studies, however, focused on the major deposits situated along the Ashanti shear zone and in the adjacent Tarkwa Basin to the east, neglecting smaller yet important occurrences, such as the Pampe deposit …
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"Invisible" Gold in Synthetic and Natural Arsenopyrite …
Abstract "Invisible" gold in hydrothermal ores is frequently scattered in the most abundant minerals of the Fe–As–S system. It is assumed that "invisible" gold does not incorporate into the mineral structure (nanoscale inclusions of the metal or its compounds) or is chemically bound (isomorphous substitution). The aim of this study is to determine …
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A review of gold mineralization in the Ashanti belt of Ghana …
The Ashanti belt of Ghana is the key district of gold mineralisation in the Palaeoproterozoic terrane of West Africa. The area considered is covered by lithologies of the volcanic/sedimentary ...
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Gold mineralization in the Ashanti Belt of Ghana; genetic …
The Ashanti belt of Ghana is the key district of gold mineralization in the Paleoproterozoic terrane of West Africa. The area considered in southwest Ghana is covered by lithologies of the volcanic-sedimentary Birimian Supergroup and the overlying clastic sedimentary Tarkwaian Group which were jointly folded and metamorphosed under greenschist facies …
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Ore Mineralogy and Mineral Chemistry of the Ashanti …
the mineralization (Hodgson, 1993). Magmatic and metamorphic origins for the fluid responsible for the gold deposits have been proposed (Kerrich and Fryer, 1979; Boyle, 1984; Burrows et al., 1986; Groves and Phillips, 1987). The gold deposit of the Ashanti mine, located at Obuasi in the central part of Ghana, is a gold-quartz vein
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Technical Report and Mineral Resource and Reserve …
1.3 Mineralization Most of the gold lodes on the Salman Trend are within the immediate footwall of the shear zone within quartz-veined silica-sericite-carbonate altered greywacke and/or granite with disseminated arsenopyrite. Some narrow, shear zone parallel zones of gold mineralization are present in the
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The Obuasi gold deposit, Ghana: A West African giant
Gold concentration mapping in individual arsenopyrite crystals from the different deposits revealed similar patterns of gold distribution: the grains possess a …
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Paleoproterozoic Gold Deposits Hosted by Albite- and
Alteration assemblages at Chirano contrast with the graphite-carbonate-pyrite-arsenopyrite-pyrrhotite assemblages that dominate the lode gold deposits in southwest Ghana, which are hosted by graphitic shear zones and Birimian sedimentary rocks. ... Gold mineralization in the Ashanti Belt of Ghana; genetic constraints of the stable isotope ...
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Supergene gold mineralogy at Ashanti, Ghana …
At the Ashanti concession, Ghana, gold-bearing quartz veins and disseminated sulphide lodes occur in narrow (1-3 m) shear zones with altered argillites and metatholeiite host rocks. The ...
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Archaean lode gold deposits in Africa: Crustal setting, …
However, cratonization in Africa, in a broad sense, was diachronous, ranging from ca. 3.0 Ga in the Barberton greenstone belt, through ca. 2.6-2.5 Ga in the Zimbabwe and Tanzanian cratons, to the ca. 2.0 Ga Eburnean event of West Africa, the latter contributing to the important gold mineralization of southwest Ghana.
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Gold mineralization in the Ashanti Belt of Ghana; genetic …
Similar compositions and wide ranges are usually attributed to sulfide generation by bacterial sulfate reduction from seawater.Arsenopyrite and cogenetic pyrite from the …
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ARSENIC CONTENT OF ARSENOPYRITE IN …
The process led to the formation of not only the ore assemblage, but also rock-forming minerals. The arsenopyrite geothermometer indicates hydrothermal arsenopyrite crystallization at a ...
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Ore Mineralogy and Mineral Chemistry of the …
The main sulfide minerals in the gold-sulfide disseminated ores are arsenopyrite, pyrite and pyrrhotite, and to a very minor extent, sphalerite and tetrahedrite. Carbonate …
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Mineralization Styles Present at the Bogoso Gold Mine
However, the principal association of gold within the Prestea and Bogoso gold districts are with arsenopyrite and arsenian pyrite. His studies depict that higher grade mineralization commonly ...
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Petrography and Geochemistry of some Granitoids …
Early workers on the Ashanti gold belt e.g. Cooper (1934) and Junner (1935) focused mainly on the visible minerals within the mineralised zones and considered gold to be younger because it is frequently included in pyrite and arsenopyrite. Leube et al. (1990) grouped gold mineralisation on the Ashanti belt into two types; Quartz Vein Type
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Gold mineralization in Palaeoproterozoic granitoids …
The world-class Obuasi gold deposit, Ghana, has gold-rich arsenopyrite spatially associated with quartz veins, which have extremely high, localised …
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Multistage gold mineralization in the Wa-Lawra …
LA-ICP-MS analysis, SEM imagery, detailed mineralogical studies coupled with EMP analysis, indicate that the occurrence of gold in the Bepkong deposit is in three …
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Ore Mineralogy and Mineral Chemistry of the …
Gold mineralisation constitutes an important economic factor in the Palaeoproterozoic terrane of West Africa. The largest and most prominent mines, with a cumulative past production in excess of 1500 t of gold, are …
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A REVIEW OF GOLD EXPLORATION IN THE NIGERIAN SCHIST …
Grades within the reef system are variable, and between oxide and ore zones, but generally 55- 100 g/t gold are found. 5. Gurmana The gurmana area of gold mineralisation is situated in the extreme Southern part of Kushaka schist belt. Gold mineralisation is in the form of quartz-sulphide veins and stock works hosted by amphibolites and gneisses.
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Edikan Mine – Perseus Mining
Gold mineralisation at Edikan occurs principally in the granite bodies, but also in classic "Ashanti-style" sediment hosted shear zones. The granite hosted gold mineralisation is free milling and occurs in two to three generations of abundant, narrow quartz veining associated with up to 3% pyrite, lesser arsenopyrite and traces of ...
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Multistage gold mineralization in the Wa-Lawra …
Section snippets Regional geology of the Wa-Lawra belt. The N-S trending Wa-Lawra belt in NW Ghana is part of the Paleoproterozoic Birimian terrane of the West African Craton (WAC; Fig. 1) and is the only N-S trending belt in Ghana (Kesse, 1985, Samokhin and Lashmanov, 1991, Pobedash, 1991, Roudakov, 1991).
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Ore Textures and their Implications for Gold Recovery at …
1 Ore Textures and their Implications for Gold Recovery at Esaase Deposit, Asanko Gold Mine K. Adomako-Ansah1, A. Boateng1, and A. Asante2 1Department of Geological Engineering, University of Mines and Technology, P.O. Box 237, Tarkwa 2Mine Geology Unit, Asanko Gold Mine Ltd Adomako-Ansah, K., Agyenim, B. and Asante, A. (2022), …
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Geology and Intrusion-Related Affinity of the Morila Gold …
At Morila, in southern Mali, during a second phase of mineralization, auriferous arsenopyrite partly replaced biotite within a zone of sulfidation along the gently NNE-plunging axis of a late fold ...
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Paleoproterozoic Gold Deposits Hosted by Albite- and
Quartz vein-associated sulphide (pyrite/arsenopyrite) and hydrothermal gold mineralisation in basement-type granitoids are the major mineralisation types in the Ahafo gold district (GMC, 2010 ...
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Simplified geology and structural setting of the …
The ~15-Moz Ahafo South gold camp is located in southwest Ghana, the world's premier Paleoproterozoic gold subprovince. Major orogenic gold deposits in the camp include Subika, Apensu, Awonsu ...
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A Review of Gold Mineralization in Mali | SpringerLink
The majority of gold deposits within the Birimian terranes of Mali, and the rest of West Africa, have been classified as orogenic gold mineralization (Milési et al. 1992; Olson et al. 1992; Lawrence et al. 2013a, b).Globally, orogenic gold lodes are shear-hosted deposits that developed along strike-slip fault systems linked to late-stage, non …
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Evolution of gold mineralization in the Ashanti Gold Belt, Ghana …
Ankerite, siderite, calcite and magnesite occur in variable proportions within all host and mineralized rocks of the Bogosu and Prestea mining districts of the Ashanti Gold Belt, Ghana. The compositions of coexisting ankerite-siderite grains establish that complex rhythmically zoned growth banding and replacement textures are present. This …
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Supergene gold mineralogy at Ashanti, Ghana …
KEVWORDS: gold, supergene mineralisation, Ashanti, Ghana. Introduction A tropical rain forest environment is character- ised by high rainfall (1250 mm per year), alternat- ing wet and dry seasons and high daily tempera- tures (20-30 ~ such that chemical weathering occurs at rapid rates. Beneath a deep soil cover
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Mesoarchaean Gold Mineralisation in the Barberton Greenstone …
In greenschist-facies deposits, the ore assemblage is dominated by pyrite and arsenopyrite, which contain up to thousands of ppm of 'invisible' gold, Ni–As–Sb sulphides and native gold. At New Consort mine, mineralisation includes massive replacement-style ore and vein-hosted or disseminated types.
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