Abstract. Gold has a special place among metals. It is the oldest metal exploited by man, it plays an important role in world economics, it is highly prized, it was the ultimate goal of alchemists, and it is stored in the vaults of banks. Gold has been used in gilding, to make funeral masks, and for many other uses.Web
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The Bajiazi gold deposit, located within the southeastern Jiapigou gold ore belt (JGB) along the northeastern corner of the North China Craton (NCC), contains > 6 tons of gold at an average grade of 24 g/t. >20 total auriferous quartz veins are hosted in the Neoarchean basement gneiss and amphibolite and are spatially and temporally …Web
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Abstract. Many gold processing plants are experiencing challenges as mining pits are becoming deeper, rocks are getting harder and more complex polymetallic and refractory ores are being ...Web
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The present research focuses on the development of a mineralogical characterization of low-grade gold ore (<0.5 g/t) using SEM-based automated image analysis (SEM-IA) to evaluate minerals association, gold exposure and elemental …Web
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Abstract and Figures Mineralogical associations and gold deportment studies are key tools in gold processing development and optimization. These tools help in the identification of the causes...Web
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A total gold extraction of 70.2% could only be reached via direct cyanidation from a refractory As-, S- and C-bearing gold concentrate calcine, and the gold extraction varied noticeably with ...Web
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It is a critical cupellation step by refining in metallurgy, where ore/precious metals/alloys are treated in fire under extremely high temperatures, and have controlled operations to …Web
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Abstract. China produces about 450 t Au per year and has government stated in-ground reserves of approximately 12,000 t Au. Orogenic gold, or gold deposits in metamorphic rocks, and associated ...Web
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Abstract. Gold Ore Processing: Project Development and Operations, Second Edition, brings together all the technical aspects relevant to modern gold ore processing, offering a practical ...Web
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Abstract— The distribution of major gold deposits in the Earth's history is discussed. The primary heterogeneity of the Archean crust in terms of gold mineralization is demonstrated. Characteristics of the main auriferous metallogenic epochs are given. The predominant associations of the orogenic gold deposits with volcanogenic massive …Web
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Show abstract. Currently, there is a lack of research on column bio-oxidation for low-grade refractory gold ore with high arsenic and sulfur content. Therefore, it is essential and significative to investigate column bio-oxidation for this type of gold ore. ... The column bio-oxidation process of refractory gold ore was characterized by a ...Web
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Gold Deposits and Their Geological Classification Robert, F.[1], Poulsen, K.H.[1], and Dubé, B.[2] 1. Geological Survey of Canada, Ottawa, Ontario, Canada 2. Geological Survey of Canada, Ste-Foy, Québec, Canada ABSTRACT Classifications of ore deposits provide essential frameworks for designing exploration strategies, evaluating prospects, andWeb
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Sampling, sample preparation, and assay protocols aim to achieve an acceptable estimation variance, as expressed by a relatively low nugget variance compared to the sill of the variogram. With gold ore, the typical heterogeneity and low grade generally indicate that a large sample size is required, and the effectiveness of the sampling …Web
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The source of fluids and their mechanism of metal precipitation in sediment-hosted, disseminated orogenic gold deposits are ambiguous. Pyrite texture, trace element, S, Pb, and He-Ar isotope compositions of sulfides and C-O isotope data of calcite from Chang'an orogenic gold deposit in the Ailaoshan orogenic belt, southwest (SW) China, …Web
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This study provided a new pretreatment method for low-grade refractory gold ore containing high concentrations of arsenic and sulfur. The main conclusions obtained were as following: (1) The all-sliming cyanidation of the bio-oxidized residue reached 81 ± 2%, the gold recovery had a 44 ± 1% increment compared with the untreated gold ore.Web
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Gold, at a grade of 8.00 g/t, is present as native gold, electrum and aurostibite. The ore also contains 2.8% pyrrhotite, together with several antimony minerals (0.8% berthierite and gudmundite ...Web
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Worldwide there are over 43 million artisanal miners in virtually all developing countries extracting at least 30 different minerals. Gold, due to its increasing value, is the main mineral extracted by at least half of these miners. The large majority use amalgamation either as the final process to extract gold from gravity concentrates or from the whole …Web
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Organic matter is commonly thought to act as a reducing agent in ore deposits (Gatellier and Disnar, 1989; Gize, 1999; Giże, 2000). For example, Gatellier and Disnar (1988) found that Au was reduced and precipitated in the presence of lignite in an Au chloride solution, which is in agreement with gold reduction at the relatively low ...Web
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Abstract. The continuum model has been one of the more widely advocated genetic models for 'gold-only' deposits such as those found in Archaean greenstone belts. It postulates that hydrothermal gold deposits were formed throughout a 20–25 km vertical crustal profile, from temperatures above 700 °C to below 180 °C, and that the ...Web
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The main minerals in the gold ore include arsenopyrite (FeAsS, PDF# 42–1320), stibnite (Sb 2 S 3, PDF# 42–1393), pyrite (FeS 2, PDF# 42–1340), and the gangue minerals including quartz and calcite. The arsenic of the gold ore is mainly present in the form of arsenopyrite and antimony in the form of stibnite.Web
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Abstract: Gold ore p rocessing is often ineffective in obtaining gold metal. Various methods have been successfully developed on an industrial scale, but small-scale gold mines are often problematic.Web
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The sequential bio-treatment of refractory carbonaceous gold ore is a promising solution to recover gold effectively by environmentally friendly technology, which includes bio-oxidation of sulfide ...Web
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Many workers accept a metamorphic model for orogenic gold ore formation, where a gold-bearing aqueous-carbonic fluid is an inherent product of devolatilization across the greenschist-amphibolite boundary with the majority of deposits formed within the seismogenic zone at depths of 6–12 km. Fertile oceanic rocks that source fluid and metal …Web
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The Sanshandao fault is a gold mineralization belt and represents the most obvious prospecting breakthrough in the Jiaodong Peninsula in recent years. The newly discovered Sanshandao marine gold deposit has reserves exceeding 400 tonnes. Gold occurs at the extension of the northern end of the fault towards the sea (Song et al 2015). …Web
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Abstract Based on comprehensive petrological, geochronological, and geochemical studies, ... Supergene processes led to the formation of oxide ore, such as the weathered and accumulated gold–iron ore, the strata-bound fracture oxide ore, and the structure-controlled vein-type ore. Most of these ore deposits are distributed along the …Web
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Double refractory gold ore (DRGO) not only include ppt levels of gold grains locked in sulfide minerals but also a problematic amount of carbonaceous matter. This causes a significant recovery loss of gold during cyanidation because of the strong affinity of the Au(CN)2− with the carbonaceous matter. Combustion decreases the carbonaceous …Web
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Abstract. Orogenic gold deposits have formed over more than 3 billion years of Earth's history, episodically during the Middle Archean to younger Precambrian, and continuously throughout the ...Web
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The application of deposit-scale structural targeting to orogenic gold deposits is primarily concerned with locating volumes of higher-grade mineralisation (ore shoots) within a broader, host structural system. Although empirical correlations between structural heterogeneities and ore shoots have long been noted and certain key physical …Web
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Abstract. To interpret the leaching rules, select suitable treatment methods, or optimize the treatment process of refractory gold ores, an in-depth analysis of ore characteristics using ore mineralogy is required. ... The gold ore less than 45 μm, 75 μm, and 100 μm accounted for 83.67 %, 97.54 %, and 99.83 %, respectively. The mineral ...Web
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For a gold ore with a head grade of 6?4 gt?1, the gold recovery improved from about 28% to 40% after microwave pretreatment. ... [Show full abstract] However, intrinsic issues of EDM, that is ...Web
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Request PDF | Geological, fluid inclusion, and H–O–S–Pb isotopic constraints on the genesis of the Bajiazi mesothermal lode gold deposit in the Jiapigou ore cluster, northeast China | The ...Web
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Graphical abstract. Download : Download high-res image (139KB) Download : ... Ore genesis of the Bake gold deposit, southeastern Guizhou province, China: Constraints from mineralogy, in-situ trace element and sulfur isotope analysis of pyrite. Ore Geology Reviews, Volume 102, 2018, pp. 740-756.Web
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Request PDF | Modelling pyrite oxidation in a refractory gold ore stockpile to estimate the gold recovery via direct cyanide leaching – A case study | This paper presents a case study of the ...Web
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The overall aim was to perform Au deportment analysis to identify the nature of occurrences of gold particles in the ore. Mineralogical studies revealed that ore is oxidized and comprised quartz ...Web
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Abstract and Figures. This paper provides chemical and mineralogical studies on Gold-bearing rock ore. The samples used was sourced from Iperindo at Ilesha Local Government Area of Osun state ...Web
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Abstract The application of deposit-scale structural targeting to orogenic gold deposits is primarily concerned with locating volumes of higher-grade mineralisation …Web
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In this study, we conducted experiments to characterize the effects on gold extraction of ores using a range of sodium cyanide concentrations (1–8 g/L), temperatures (40–75 °C), and oxygen …Web
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