The Albazino deposit consists of several seemingly isolated northwest-trending mineralisation zones separated by fatult-bounded structural blocks. Mineralisation extends over 7 km in length with the Anfisa, Olga, Ekaterina and Farida zones in the northeast, and Nadezhda in the northwest.

Gold mineralisation at Albazino is of the low-sulphide, gold-pyrite-arsenopyrite type, and is assicated with moderately dipping dykes that crosscut sandstrones. The most intense gold mineralisation is associated with fold zones, averaging between 10 and 30m in thickness with intense veining.

Albazino is mined by conventional open-pit truck-shovel and drill-and-blast methods. The current life-of-mine plan provides for open-pit mining until 2031, with further extensions anticipated as a result of pit enlargement and additional exploration activities, particularly exploration at the Ekaterina and Farida ore zones.

At Albazino, underground mine productivity continued to improve as a result of the full transition to a partially cemented waste backfill. The new mining method had a positive impact on grades that offset slightly lower recovery levels, impacted by near-surface, partially oxidised ore from Ekaterina-1.

Here, the run-of-mine ore is fed to the primary jaw crusher and reduced to 250 mm which is then subject to three-stage milling (in one SAG mill and two ball mills) followed by two-stage conventional flotation in parallel circuits. The flotation concentrate is then thickened, filtered, dried, bagged and shipped to the Amursk POX facility for further processing, while the flotation tails are thickened and sent to the valley-fill tailings storage that is lined with an impoundment dam.

The Albazino concentrator has been running at its full 1,600 ktpa design capacity since its launch in 2011. The bench scale autoclaving test work on the Albazino concentrate was carried out at SGS in Canada and achieved CIL gold recoveries from oxidised concentrate as high as 96%. An extended pilot plant run achieved a cyanide leach gold recovery of 95 per cent by CIL treatment of the POX discharge.

Pressure oxidation, also known as autoclave leaching, was selected as the preffered processing option for the Albazino and Mayskoye refractory gold deposits. This process is particularly well suited for treating refractory ores that give low recovery rates when directly leached with cyanide.

The Amursk POX hub is Russia’s first pressure oxidation plant, and one of Polymetal’s largest projects that combines operations around oneprocessing facility. The hub currently comprises two high-grade refractory gold deposits, Albazino and Mayskoye, and three processing facilities — the Albazino and Mayskoye concentrators, and the Amursk hydrometallurgical plant that uses POX technology for processing refractory ore.