Native gold from seven placers of the Amyl-Sistighem ore placer region (the Republic of Tyva, Krasnoyarsk region) is classifed on the basis of its structure, morphology and chemical composition, which are studied by optical and electronic microscopy. Three chemical types of native gold are identifed: Ag-Au, Hg-Ag-Au, Cu-Ag-Au. There are rounded and angular particles with and without a high-fneness rim. Seventeen types of native gold are established on the basis of combination of various characteristics. These varieties characterize the mineralogical-geochemical types of primary ores, the distance of the transportation of clastic material, the degree of mechanogenic and crystallophysical deformations of gold particles, and the duration of their occurrence in a gold-bearing layer under relatively calm conditions. Our results can be used in planning thematic pre-project and prospecting-assessing work at this territory, whereas methodological issues can be applied in other gold placer areas.

Keywords: placer, placer gold, typomorphism, structural-morphological varieties, gold fneness, classifcation, electron microscopy, primary source.

Acknowledgements. The authors are grateful to S.G. Prudnikov and R.V. Kuzhuget for thorough help and support of studies and S.A. Sil’yanov, B.M. Lobastov and N.V. Nelyubin for help in preparation of samples and electron microscopic studies of gold particles. We also acknowledge Reviewer R.S. Palamarchuk and Editors of Mineralogy for their comments and advices during the fnal editing of the manuscript.

Confict of interest. The authors declare that they have no conficts of interest.

Author contribution. Ch.M. Khertek, A.M. Sazonov – conceptualization, investigation, writing – original draft; A.M. Sazonov, Ch.M. Khertek – visualization, writing – review & editing. All the authors approved the fnal version of the manuscript prior to publication.

For citation: Khertek Ch.M., Sazonov A.M.Types of gold placers of the Amyl-Sistighem placer region, West Sayan. Mineralogy, 10 (1), 32–53. DOI: 10.35597/2313-545X-2024-10-1-3.

Received 29.11.2023, revised 30.01.2024, accepted 11.03.2024

Ch.M. Khertek, Tuvinian Institute for Exploration of Natural Resources SB RAS,
ul. Internatsionalnaya 117, Kyzyl, 667007 Russia; chayana83@mail.ru

A.M. Sazonov, Siberian Federal University, pr. Svobodny 79, Krasnoyarsk, 660041 Russia; Sazonov_am@mail.ru

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