FORMATION OF THIN GOLD OXIDE FILMS ON THE NATIVE GOLD IN NATURAL CONDITIONS
Film-thick coating of gold oxide covering both placer and primary ore gold grains has been detected by systematic studies using the Auger electron spectroscopy in TsNIGRI. These oxide coatings on placer gold grains are very thin (no more than 10—20 nm) and have scattered distribution. Oxide films on the primary gold grains are continuous and much thicker ones (350 nm and more). Presence of these gold oxide coatings cannot be attributed only to supergenic oxidation, because they may have been inherited from primary ore also. The paper, by example of Novogodnee-Monto gold ore deposit (the Polar Urals), shows conditions needed for development of these gold-oxide films and connected with them peculiarities of the «new gold deposition» in the weathering crust.