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Showing 1 to 11 of 11 for “"Fire assay"”.
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Fire Assay, Cupellation and the Dissemination of Technical Knowledge in Post-Medieval Europe
This PhD thesis focuses on the study of assaying practices in the post-medieval Europe (c. 14th-17th centuries), especially on silver assaying. Modern analytical chemistry is an offspring of fire assay and cupellation, a method used to quantify the amount of precious metals such as silver and gold …
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Analysis of platinum, palladium and rhodium at trace concentrations in lead using the time resolved spark emission technique called SAFT
The fire assay technique may be used to extract noble metals from platinum bearing ores. It allows for the use of relatively large quantities of ore sample from which trace quantities of noble metals are concentrated. The fire assay with lead as the collector is one such procedure, where …
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A study of epigenetic mineralisation in the Central Zone of the Damara Orogen, Namibia with special reference to gold, tungsten, tin and rare earth elements
… spectrometry, atomic absorption spectrometry, fire assay and infra-red spectroscopy), mineral chemistry studies (electron microprobe and X-ray diffraction) and geochronological work (Rb-Sr whole-rock and mineral age determinations and Pb-Pb model ages) to examine epigenetic mineralisation in …
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A study of the geochemical behaviour of anthropogenic platinum-group elements in a mixed urban-rural catchment: the River Stour, Kent, U.K.
… river sediments were analysed for PGE by NiS fire assay pre-concentration and ICP-MS. The highest element abundances occur in a sample of ashed sewage sludge (total PGE content of 392 ng/g), whilst the lowest values were recorded in the soils and sedimentary rocks. The total PGE content of the …
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Development of rapid techniques based on selective dissolution for the determination of the precious metals in geological samples
… that had been independently analysed by NiS fire assay as well as appropriate reference materials. This extraction procedure, with direct analysis of leachates by ICP-MS, was also used as the primary technique for characterising the homogeneity of two new chromitite reference materials, …
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Platinum-group elements geochemistry of felsic rocks
… were carried out using a modified precise NiS fire assay - isotope dilution method. The Ambae and Pual Ridge studies showed that Cr spinel is an important host for Rh, Ir, Os and Ru in oxidized ultramafic-mafic arc magmas and that a Pt-alloy can crystallize from an arc-type basaltic-andesitic …
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Platinum-group elements geochemistry of felsic rocks
… were carried out using a modified precise NiS fire assay - isotope dilution method. The Ambae and Pual Ridge studies showed that Cr spinel is an important host for Rh, Ir, Os and Ru in oxidized ultramafic-mafic arc magmas and that a Pt-alloy can crystallize from an arc-type basaltic-andesitic …
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Distribution of gold in soils and stream sediments and the use of cyanidation in exploration geochemistry
… (S.G. 3.3), samples were analyzed for gold by fire assay-atomic absorption spectroscopy (FA-AAS) and cyanide-AAS (CN-AAS). Results indicate that, on average, 70% of the gold in soils and 67% of the gold in stream sediments resides in the finest fraction (-53 μm, -270 ASTM). Furthermore, …
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Application of platinum-group element (PGE) geochemistry to select geological problems
… platinum-group elements (PGEs), analysed by the fire-assay isotope dilution method, to determine the timing of sulfide saturation in an evolving magma system, which in relation to volatile saturation is one of the most important factors controlling magma fertility. The time gap between these two …
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Application of platinum-group element (PGE) geochemistry to select geological problems
… platinum-group elements (PGEs), analysed by the fire-assay isotope dilution method, to determine the timing of sulfide saturation in an evolving magma system, which in relation to volatile saturation is one of the most important factors controlling magma fertility. The time gap between these two …