MORPHOLOGICAL AND CHEMICAL CHARACTERISTICS OF NATIVE GOLD FROM DETRITAL ENVIRONMENTS: IMPLICATIONS FOR TRANSPORT AND SOURCE PROXIMITY
DOI:
https://doi.org/10.46763/Keywords:
mapping; discontinuities; cadaster; classification; sclerometer; excavationAbstract
In this study, an integrated morphological and chemical analysis of native gold from alluvial deposits was conducted in order to determine the relationship between grain morphology, chemical composition, and the distance from the primary gold source. The investigation was carried out using scanning electron microscopy (SEM), whereby the morphology, surface texture, and microstructural characteristics of the gold grains were analyzed, along with their chemical composition (Au, Ag, and Fe). The results indicate significant variability in Au (88.73–99.53 wt.%) and Ag (0.47–9.19 wt.%) contents, whereas Fe is present only in trace amounts. A clear trend of increasing gold fineness with decreasing silver content is observed. Morphologically, the analyzed gold aggregates are predominantly characterized by irregular and angular forms, indicating limited transport and close proximity to the primary source. In addition, grains exhibiting flattened, lamellar, and rounded morphologies are present, which are typical of more distal positions relative to the primary environment. The obtained results confirm that the application of SEM-based morphological and chemical analyses represents a valuable approach for determining transport distance and for assessing the location of primary gold-bearing sources.
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