Institute of Mineralogy, Geochemistry and Crystal Chemistry of Rare Elements IMGRE (Moscow, Russia):

Levchenko E. N., Deputy General Director, Doctor of Geological and Mineralogical Sciences, lev_imgre@rambler.ru

Institute of Ore Deposit Geology, Petrography, Mineralogy and Geochemistry of the Russian Academy of Sciences (IGEM RAS) (Moscow, Russia):
Grigoreva A. V., Senior Researcher, Candidate of Geological and Mineralogical Sciences

The industrial value of complex rare-metal-titanium placers depends not only on the contained titanium and zirconium minerals, but also on the associated minerals and valuable components. When studying rare-metal-titanium, titanium-containing and rare-metal placers, gold is found in various quantities. The production of gold-bearing concentrate, a readily marketable commercial product, may significantly increase the economic efficiency of the development of complex placers. In recent years, technogenic gold deposits have been recognized as a huge and poorly explored mineral resource for the gold industry in Russia and abroad. The article presents the results of a typomorphic study and content data for the native gold contained in Russian complex rare-metal placers of natural and technogenic origin included in the State Balance. Significant gold grades (over 0.1 g/t) were found in the original ore sands of the Tsentralnoe (Tambov Region), Beshpagirskoye (Stavropol Territory), and Nikolaevskoye (Kemerovo Region) deposits, as well at the Tsentralnaya-Nizhnyaya technogenic deposit (Republic of Sakha-Yakutia). Native gold of the placers studied is mainly represented by thin, mechanically processed particles with the predominant particle sizes of 0.1 to 0.044 mm. The gold particles are fully liberated and have a number of signs of transit, which is quite consistent with the genesis concepts of the deposits. The coefficient of variation for the grade and distribution of Au by the particle size classes of the original sands changes over a wide range.

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