The results of the study of placer gold content in the Arctic shelf regions of Russia allow us to identify the main geological and industrial types of placers and determine their resource intensity. For placers of coastal-marine genesis the problem of fine gold extraction for sampling and exploitation is acute, which is successfully solved by using modern domestic enrichment apparatuses. High economic efficiency of exploitation of buried placers on coastal-marine plains, shallow shelf and on islands from under glaciers can be achieved by application of borehole hydro-technology of extraction developed in Russia.

Studies on the autoclave oxidation of nickel sulfides mainly consider the behavior of fused nickel sulfide, close in composition to heazlewoodite Ni₃S₂. Only a few have highlighted the kinetics of dissolution of nickel monosulfide NiS, one of the main components of various intermediate products of nickel production: anode slimes, nickel sulfide concentrate obtained by precipitation with hydrogen sulfide, and the intermediate phase of autoclave dissolution of nickel concentrate from flotation of copper nickel matte...