Meretukov M. A., Research Adviser, Professor, Doctor of Engineering Sciences, e-mail: mamer@inbox.ru

New scientific courses, including nanogeochemistry and nanomineralogy, helped to obtain the data, which make it possible not only to specify the deposits genesis and to estimate new gold-containing objects, but also to choose optimal technological decisions during the metallurgical processing of refractory ores. Presence of nanoparticles of metals, oxides, sulphides and silicates is typical for metal-containing sulphide ores, soils, aerosols etc. High-temperature geochemical reactions, which make it possible to generate nanocrystals, have the following examples: nucleation from liquids; sedimentation from sublimates; segregation in minerals (salting-out) and reactions between minerals. Appearance and concentration of nanoparticles in natural conditions is caused by geochemical processes, which define a high grade of supersaturation of elements in solutions, which are the consequence of inorganic or biological processes. Mixing of fluids, which are ingrained through ore body, with near-surface oxygenated cold water flows, causes the sedimentation of nanoparticles of oxygen compounds of iron, magnesium, aluminium and silicon. As a result of high chemical, sorption and redox activity, these compounds play an important role in migration of elements and realization of surface biochemical processes. Rare changes of properties, which are characteristic for water solutions in nanoporous minerals, define the increasing of their capability to complexing, sorption and sedimentation processes. Nanopores, universally spread in geological formations, are the component parts of total rock porosity. It is supposed that such channels in porous structure of minerals provide the possibility of mass carry with various geochemical reactions and, pehaps, play a role of geochemical barrier.