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Showing 1 to 17 of 17 for “"supergene"”.
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Process mineralogical characterisation of the Kansanshi copper ore, NW Zambia
… is mineralogically and texturally complex due to supergene enrichment resulting in the presence of a variety of primary and secondary copper minerals. This necessitates the processing of ore through three separate circuits: sulphide flotation, mixed flotation and oxide leach, followed by solvent …
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A study of the vein copper mineralization of the Virgilina district, Virginia and North Carolina
… hypogene deposition and a significant phase of supergene alteration. Hypogene mineralization, 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 …
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Trace Elements and Sulfur Isotope Variations in Endowed and Non-Endowed Porphyry Systems of the Dawson Range Mineral Belt, Yukon Territory
… Argillic’ for alteration zones, and ‘Hypogene ≤ Supergene sulfide ≤ Supergene oxide’ for weathering profiles. Notably, the argillic alteration exhibited the widest δ³⁴S range, reflective of complex sulfur sources and processes. The δ34S values provide valuable insights into the provenance, …
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Upper Conglomerate and its importance to the Sierra Mojada Ag-Zn deposit system, Coahuila, Mexico, The
… in northern Mexico by the extreme development of supergene oxidation. This study suggests that the supergene oxidation was related to significant Quaternary to recent normal faulting and uplift.
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Determining the Genes for Distyly in Turnera
… least three tightly linked genes constituting a supergene. The S-locus genes responsible for distyly in Turnera had not been determined. Using deletion mapping and chromosome walking, the S- and s-haplotypes of the S-locus were constructed. Three hemizygous genes, TsSPH1, TsYUC6, and TsBAHD occur …
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Geology, geochemistry, and genesis of the El Peñón epithermal Au-Ag deposit, northern Chile : characteristics of a bonanza-grade deposit and techniques for exploration
… 70-69 Ma and 50-49 Ma, respectively. Dating of supergene alunite indicates that weathering within a semi-arid to arid climate occurred from 23-17 Ma, prior to the onset of hyperaridity. The veins that comprise the El Peñón deposit range from <0.5 m to 22 m wide; the bonanza-grade Quebrada …
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The stratigraphic and structural controls on copper-gold mineralization at Cassenha hill prospect, within the Archean to Paleoproterozoic Angolan shield, Congo craton, South Western Angola
… ± chalcopyrite ± other copper sulfides, and supergene ore (stage II) consisting of malachite ± azurite ± chrysocolla, which represents the prevalent mineralization at the prospect. The δ 18O value of quartz veins range from +12.81 to +13.53‰, while the δD of chlorite minerals range from -51 …
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Iron minerals in sedimentary phosphorites of the southeastern United States
… and iron oxides as inclusions in phosphorites, supergene ferrian-millisite [Ca₃(Al,Fe³⁺)₁₂(PO4)₈(OH)₁₈ • 6H₂O)] as coatings on phosphorites in the leached zone under a central Florida gossan, and secondary ferromanganese oxide spherulites as accessory minerals in Tennessee deposits are made in …
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Gold-enriched rims on placer gold grains: an evaluation of formational processes
… ligands for the transport and redeposition of supergene gold. Electrolytic refining of placer Au-Ag grains is also a process for forming gold-enriched rims that can operate together with secondary enrichment to produce the observed phenomena.
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Assessing the geologic sources of manganese in the Roanoke River watershed
… provides support that the ore deposits are supergene in origin, consistent with previous work. Spatial correlations between Mn ore locations and stream terrace deposits support a model of ore formation in which Mn-oxides were precipitated near discharge zones as anoxic groundwater mixed with …
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Mineralogical, textural, and paragenetic studies of selected ore deposits of the Southeast Missouri lead-zinc-copper district and their genetic implications
… quartz indicating the introduction of possible supergene solutions at the end stages of mineral deposition.</p> <p>The general paragenetic sequence corresponds with mineral zoning and is similar throughout the entire lead district. Most importantly, the paragenetically early Cu-Co-Ni sulfides …
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Geology of the Alice E. breccia pipe and vicinity, New World mining district, Park County, Montana
… vertically and laterally about the breccia. Supergene alteration has resulted from the oxidation of pyritic ores enriching gold relative to other metals at the Alice E. mine. Mineralization consisting of vein and replacement types occurs in association with the hydrothermally altered areas. …
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Electrical and seismic responses of shallow, volcanogenic, massive sulphide ore deposits
… removed first order parameters prove useful. The supergene and gossan zones are defined as sources of electrical anomalies and correlate with interpreted SP sources. Seismic velocities of fresh Woodlawn ore samples indicate only small contrasts with host rocks. Refraction travel-time data are …
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Microbial carbon within and above exotic copper deposits in northern Chile : implications for ore genesis and exploration
… unusual, but characteristic, by-product of the supergene enrichment of Cenozoic porphyry Cu deposits in northern Chile. Carbon stable isotopic analysis is employed herein to clarify the environment of exotic ore formation and to provide guidelines for the exploration for non-outcropping …
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Characterization of Thy-1 expression on human hematopoietic cells
… surface protein belonging to the immunoglobulin supergene family. This was established by isolation and sequencing of a cDNA cloned by immunoselection of COS cells transfected with a cDNA library derived from a 5E10⁺ cell line. 5E10 staining of hematopoietic cells from human fetal liver, cord …
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Geology, petrology and geochemical characteristics of alteration zones within the Seridune prospect, Kerman, Iran
… 0.5 V) solutions control the abundance of other supergene minerals (e.g. malachite and azurite) above the groundwater table. The composition of felsic intrusions, geometry of hydrothermal alteration zones, mineralization styles (porphyry and vein types) and similar geochemical parameter with …
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A single-crystal EPR study of radiation-induced defects in selected silicates
… so it is a natural sink for attenuating As in supergene non-sulfide Zn deposits and Zn mine tailings. Hemimorphite commonly contains elevated contents of heavy metalloids such as As, Cu, Cd, and Pb. Cation-exchange experiments of hemimorphite with 0.1M CaCl2 solution at 110°C show that As and …