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Richards Bay zircon.Pietersen, Kevin John. January 1992 (has links)
Zircon from the zircon concentrate of Richards Bay Minerals was investigated with a view
to understanding the morphology and provenance. The obsevations were applied to the reduction of
uranium, thorium and other trace elements in the heavy mineral placer deposits. It is evident from
differences in morphology, optical characteristics, cathodoluminescence, inclusion types and trace
element analyses that the zircon is derived from numerous parent rocks. Rare earth element
modelling reveals several possible parent rocks including rhyolites, granites, syenites, pegmatites and
carbonatites.
Fission track U mapping of individual zircons indicated an enrichment of U in the rims and
grain terminations. The U maps were used to devise and test several methods, including abrasion and
partial dissolution, to reduce the combined U and Th concentration from 450-563ppm to below
400ppm. The effect of magnetic cleaning, density separation and size classification of the zircon
concentrate on the U +Th concentration was found to be negligible. Air abrasion and HF acid
dissolution successfully reduced the U +Th concentrations to between 332 and 383ppm.
The contribution of trace elements from inclusions, surface pit fillings and coatings, and
foreign minerals within the zircon concentrate were evaluated by by scanning electron microscope
identification. / Thesis (M.Sc.)-University of Natal, Durban, 1992.
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GOLD DISTRIBUTION AND SAMPLING OF THE DESERT ALLUVIAL FAN PLACER AT COPPER CANYON, LANDER COUNTY, NEVADA.Deakin, Frank Apland., Deakin, Frank Apland. January 1982 (has links)
No description available.
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A geochemical and morphological investigation of placer gold grains from the southern Seward Peninsula, Alaska : implications for source and transport mechanismsGauntlett, Ernest John Herbert January 2015 (has links)
[Partial abstract]: This study presents the first detailed geochemical and morphological characterisation of gold grains from the southern Seward Peninsula, Alaska, a region with significant historical and on-going placer gold mining. Quantitative Au, Ag, Hg, and Cu data are presented for gold grains from eleven sites. Additionally, quantitative Te, W, As, and Sb trace element data are presented for gold grains from ten of the eleven sites. Although it is acknowledged that quantitative trace element analysis of gold grains is a relatively new endeavour, the limited trace element data obtained in this study suggest that trace element analysis could be useful for characterising gold sources on the southern Seward Peninsula. Major and minor element geochemical profiling is sufficient at differentiating between sites from regional provenance systems but insufficient at differentiating between sites within a single system. Differentiating among sites within a single system will likely require microchemical analysis of mineral inclusions and analysis of trace element signatures.
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