The Russian Federal Agency of Subsoil Resources has completed evaluation of the results of the public tender for reassessment of the Udokan copper deposit.

The Russian Federal Agency of Subsoil Resources has completed evaluation of the results of the public tender for reassessment of the Udokan copper deposit. FSUE Giprotsvetmet, the leading designer of base metal plants, won the tender. MMC Norilsk Nickel, the largest producer of base and precious metals, will take part in this reassessment. The primary objective is to prepare a new feasibility study for Udokan copper deposit.
The State Reserve Commission of the USSR approved the results of the baseline feasibility assessment, the amount and quality of known resources and the decision on feasibility of commercial mining of the deposit in 1981. In the following years a number of technical assessments and cost analyses were performed. However, market changes, primarily metal prices, and ore processing technologies have brought forward the need to reassess the world’s major copper deposit. Such assessment is complicated by copper occurrence in two ore types (oxide and sulfide), which calls for the development of at least two different ore processing technologies. Since only one processing technology is required it will be developed by technology experts from research institutions while Norilsk Nickel experts will collect representative samples, analyze their chemical composition and finally accumulate hundreds of tons of ore from underground workings. The Company has all necessary data for ore sampling: electronic model of the deposit and plans of existing underground workings and the unique experience in rehabilitation of underground workings and ore sampling in the Far North and Trans-Baikal territories.
Complex local ores include three types of mineralisation: sulfide (oxidized copper content up to 30%), mixed (oxidized copper from 30% to 70%) and oxide ((oxidized copper over 70%). Mineable ore reserves breakdown: sulfides 43%, mixed 40%, oxides 17%. Balance reserves include 1,310.8 Mt of ore, 19.7 Mt of copper (average grade 1.51%) and 11,900 t of silver (average grade 9.6 g/t).