Chersky Institute of Mining of the North, Siberian Branch, Russian Academy of Sciences, Yakutsk, Russia:

S. M. Tkach, Principal Researcher, Doctor of Engineering Sciences, tkach@igds.ysn.ru
S. A. Batugin, Principal Researcher, Professor, Doctor of Engineering Sciences
I. D. Barakaeva, Researcher, Candidate of Engineering Sciences

In focus is the modern approach to ore dilution assessment as one of the ways of enhancing mineral resource potential based on increase of knowledge on geological resources. It is emphasized that the majority of ore deposits and placers, especially in the northeast of Russia, are structured as clusters where zones of high-grade ore and gold make on average 10–30% and seldom to 60%, containing the most part of ore and gold reserves and other useful minerals (85% and above). The article shows that the current practice of mineral exploration, appraisal and mining improperly accounts for the initial, naturally “given” property of mineral resources—their geological dilution, since mineralization is naturally nonuniform mineralization, on the one hand, and since mineral body mapping is implemented in accordance with the current standards of exploration and appraisal, on the other hand. It is required to take into account the economic-geological dilution as early as the stage of mapping of productive strata, including zones of barren rock or zones of rock and ore with substandard concentration of useful components (from 50 to 95% almost for all types of ore deposits and placers). The proposed approach to ore dilution assessment, with an integrated index, includes process dilution (in the course of mining) and new sub-indexes of structural dilution (due to discordance of mapped and actual limits of ore bodies and extraction panels) and economic-geological dilution (governed by naturally nonuniform content of useful components and by standards of appraisal and mapping of mineral reserves). This approach contains high potential of enhancing efficiency of mineral mining using advanced technologies (selective and separate extraction, grading, pre-treatment, leaching, formation of lower-grade mineral deposits for later on extraction of useful components, etc.) aimed at minimization of offgrade ore and gold mining and processing.

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