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Showing 1 to 19 of 19 for “"Chalcocite"”.
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Nonstoichiometry of chalcocite in water-xanthate systems
… involving different Cu/S ratios that pertain to chalcocite, djurleite, anilite and covellite. Calculations were completed for cases where oxidation of the sulfur proceeded to i) elemental sulfur, ii) thiosulfate, iii) sulfate and iv) destabilized sulfate. Stability regions for each copper sulfide …
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Thermodynamics and electrochemistry of the chalcocite-potassium ethyl xanthate system
… calculations have been carried out on the chalcocite-KEX-water system based on complete mass balance equations which include both soluble and insoluble species. The calculations have yielded i) E<sub>h</sub>-pH stability diagrams for different KEX additions, ii) equilibrium concentrations …
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Investigating the Influence of the Electrochemical Environment on the Flotation of a Mixed Sulphide Mineral System of Bornite and Chalcocite
… of two copper sulphide minerals: bornite and chalcocite. The focus areas include; collector-mineral interaction, surface charge and flotation recovery of the bornite and chalcocite under varying pH conditions. For this investigation, the interaction of collector with bornite and chalcocite are …
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A study of the vein copper mineralization of the Virgilina district, Virginia and North Carolina
… in decreasing order of consists of bornite, chalcocite/djurleite, an ilite, digenite, chalcopyrite, pyrite, magnetite, ilmenite, rutile, hessite, and gold (fineness 850). Supergene mineralization, in decreasing order of abundance is malachite, covellite, cuprite, digenite, hematite, …
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Adsorption of dextrin onto sulphide minerals and its effect on the differential flotation of the Inco matte
The major constituents of the Inco matte, chalcocite (Cu2S) and heazlewoodite (Ni3S2), are separated by differential flotation with diphenylguanidine as collector. To select an effective organic depressant, many dextrins were tested and tapioca dextrin 12 was found to have an exceptional affinity …
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Non-hydrolytic Sol-gel (NHSG) Synthesis of Transition Metal Sulfides and Theoretical Investigations
… five different polymorphs, metastable hexagonal chalcocite, monoclinic chalcocite, djurleite, low digenite and covellite, was achieved by fine tuning synthetic parameters. In addition, a continuous phase evolution from copper rich phases towards copper deficient phases between chalcocites and …
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Kinetic Studies of Sulfide Mineral Oxidation and Xanthate Adsorption
… Pyrite, pyrrhotite (pure and nickel activated), chalcocite and covellite were studied in 10-4 M ethylxanthate solution at pH 6.8 at temperatures in the range of 22 – 30 0C. The Tafel studies showed that xanthate adsorbs as dixanthogen (X2) on pyrite and pyrrhotite, nickel dixanthate (NiX2) on …
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Re-evaluation of Kombat-style mineralisation and implications for exploration in the Otavi mountainland, Namibia
… bornite, covellite, and galena with minor chalcocite, sphalerite, and pyrobelonite, for the Cu-Pb MVT-type ores. For the Fe-Mn ores, hausmannite, hematite with minor, manganite may be are considered.
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Mathematical modelling of agglomerate scale phenomena in heap bioleaching
… theoretical case study ore that contains mainly chalcocite and pyrite, in the presence of iron oxidizing microbes. The numerical implementation of the model is done in the Python programming language. The integrity of the numerical results is confirmed by performing mass balance checks at the end …
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The Marcona - Mina Justa District, South-Central Perú: Implications for the Genesis and Definition of the Iron Oxide-Copper (-Gold) Ore Deposit Clan
… ensuing chalcopyrite - bornite - digenite - chalcocite - hematite - calcite mineralization was entirely the product of non - magmatic, probably evaporite-sourced, brines. Marcona and Mina Justa therefore represent contrasted ore deposit types and may bear minimal genetic relationships. The …
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Stabilizing Degenerate Dopants in Colloidal Semiconductor Nanocrystals
… demonstrate identical absorption bands in low-chalcocite copper-sulfide nanocrystals with and without cation vacancies. This work demonstrates that cation vacancies internal to the nanocrystal lattice are far more effective at stabilizing free carriers than anions at the nanocrystal surfaces. …
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Fundamental studies of thionocarbamate interactions with sulfide minerals
… that IPETC and IBECTC adsorption on copper and chalcocite are dependent on potential. This has been verified by contact angle and in-situ spectroelectrochemical measurements. Microflotation tests with these thionocarbamates show that the floatability of Cu₂S and CuFeS₂ is dependent on pH. The …
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The synergistic interaction between dithiophosphate and frothers at the air-water and mineral-water interface
… of DTP on galena, pyrite, chalcopyrite and chalcocite was measured by UV-Vis spectrophotometry and isothermal titration calorimetry. Adsorption tests in the presence of aeration were used to determine if DTP dynamically transferred from the air-water to the mineral-water interface. At the …
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Enhancing the recoveries and grades of Cobalt from Nchanga and Konkola Ores of KCM
… as chalcopyrite (CuFeSz), Bomite (CusFeS4) and Chalcocite (CujS). However, the recoveries of cobalt minerals in both Concentrators are low (45-50%TCo). In this work, a combination of the electrokinetic, Ultra-Violet spectrometry, X-ray Photoelectron spectrometry, contact angle measurements and …
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Enhancing the recoveries and grades of Cobalt from Nchanga and Konkola Ores of KCM
… as chalcopyrite (CuFeSz), Bomite (CusFeS4) and Chalcocite (CujS). However, the recoveries of cobalt minerals in both Concentrators are low (45-50%TCo). In this work, a combination of the electrokinetic, Ultra-Violet spectrometry, X-ray Photoelectron spectrometry, contact angle measurements and …
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Metallogenesis of Cu deposits in Upper Palaeozoic sedimentary rocks, southern Ireland
… tetrahedrite/tennantite, minor bornite and chalcocite. Re-Os geochronology measurements on molybdenite samples, associated with the vein hosted copper sulphides, reveal ages of 367.3 ± 5.5 to 366.4 ± 1.9 Ma (Upper Devonian, syn-basinal) for the Allihies deposit on Beara Peninsula, and from …
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Heavy-metal-free colloidal nanocrystal heterostructures – synthetic chemistry and growth mechanisms
… precursor reactivity. Nanorods are predominantly chalcocite at the early stages of growth but a phase transition to djurleite occurs accompanied by a change in tip faceting upon further growth. In contrast, nanodisks appear in the djurleite phase early on and remain so upon continued growth. …
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Composition and fabric of the Kupferschiefer, Sangerhausen Basin, Germany and a comparison to the Kupferschiefer in the Lubin Mining District, Poland
… in mineralized samples from both locations is chalcocite, followed by chalcopyrite. Sulfide mineralization is commonly associated with the presence of quartz and carbonate veins in Lubin mining district samples, while mineralization is rarely associated with these veins in Sangerhausen Basin …
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Investigation of the Geology, Structural Setting and Mineralisation the Copper-Sulphide Deposits in the Messina Area, Limpopo Mobile Belt, South Africa
… of pyrite, chalcopyrite, sphalerite, bornite, chalcocite and minor pyrrhotite and galena as well as traces of pentlandite, tennantite, mollybdenite, cobaltite and tetrahedrite. This confirms that the Messina copper deposits had complex sulphide ore mineralisation that is typical of hydrothermal …