First Evidence of the Archean Age of Orogenic Gold of the Russian Part of the Karelian Craton (Fennoscandian Shield): Sm–Nd Mineral Isochron for Gold-Bearing Metasomatites of the Novye Peski Deposit

One unsolved problem of Archean metallogeny of the Russian part of the Fennoscandian Shield is related to the period of formation of orogenic gold deposits, the age of which was previously considered Early Proterozoic. Comprehensive studies identified the complex evolution of ores from the Novye Peski deposit and the first Neoarchean Sm–Nd isochron isotopic age (2583 ± 16 Ma) of the formation of orogenic gold of the Karelian Craton. A significant positive ε Nd( t ) value of +4.7 of gold-bearing metasomatites probably points to the link between the ore-forming fluid and the deep mantle source.