National Polytechnic University of Armenia, Erevan, Armenia:

A. G. Oganesyan, Director, Professor, Doctor of Engineering Sciences, armen.hovhannisyan@polytechnic.am
A. T. Bagdasaryan, Head of Department, Associate Professor, Candidate of Engineering
Sciences
R. L. Atoyan, Fellow Applicant

Evaluation of mineral resources and mineral reserves is the disclosure of the mineral and commercial potential of a deposit by means of solving complex geological and economic problems. The estimate depends, among other things, on the geotechnical and hydrogeological conditions of a deposit. Selection of a mining method is a higher-priority problem in translation of mineral resources to mineral reserves. One of the ore quality standard parameters is the maximal permissible off-grade ore or barren rock interval inclusible in the estimated reserves based on the geological and geotechnical conditions of mineral mining, which govern the technology and equipment to be used. On the basis of geological exploration data, a variant calculation of the reserves of ore and gold was made per estimation blocks (ore bodies), which revealed a pattern of change in the ore and gold reserves and in the content of gold in ore as a function of the mentioned parameter of the ore quality standard. A distinctive feature of this problem is the multiplicity of solutions which meet the technical, technological and organizational requirements. To determine the optimal value of the said parameter, on the basis of the optimality criterion of the maximum profit for the entire period of mining, the patterns of the commercial product (Dore alloy) cost, the haulage and processing costs and the profit size are obtained. The maximal permissible off-grade ore or barren rock interval parameter is applicable in appraisal of ore reserves at Sotk gold ore and similar deposits.

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