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 2034, with further extensions anticipated as a result of pit enlargement and additional exploration activities.
|Location||Khabarovsk Region, Russia|
|Key exploration projects||Albazino flanks|
|Processing||1.6 Mtpa flotation followed by POX and CIL processing at Amursk|
|Reserves (JORC)||1.5 Moz GE, 3.8 g/t average grade|
|Resources (JORC)||2.2 Moz GE, 4.2 g/t average grade|
|Production start date||2009|
|Life of mine||2045|
Albazino, acquired in 2006, is a high-grade refractory gold mine developed as a Greenfield project by Polymetal. Today, it comprises an operating open-pit mine and a 1.6 Mtpa on-site flotation concentrator that was first launched in 2011. Albazino is an integral part of the group’s largest project — the Amursk POX Hub, where Albazino gold concentrate is transported and then processed into dore bars.
The Albazino area has been a site of active placer gold mining since the 1890s, with first hard-rock gold discovered during prospecting activities in 1955. However, exploration activities were quickly suspended once the refractory nature of gold mineralisation was revealed.
Polymetal acquired Albazino in 2006 from a local placer miner for US$ 7 million, making it the Group’s first greenfield project since 2004. Active exploration on site commenced in 2007, and the first JORC reserves estimate was confirmed by a feasibility study in the second quarter of 2008. The same study also confirmed that the Albazino project can be economically developed as an open-pit operation with a 1.6 Mtpa conventional flotation plant and a pressure oxidation facility. Construction of the Albazino concentrator started in the third quarter of 2008 and was successfully launched with the first gold concentrate bagged in April of 2011. The same year, first concentrate shipments were made to third-party off-takers in China while the Amursk POX facility was under construction.
From the moment of its acquisition to the launch of production, a total of US$ 342 million was spent at Albazino comprising exploration, project capex, ongoing overhead, and first-fill working capital.
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 associated 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 ore is refractory, with the majority of gold intimately associated with arsenopyrite and pyrite in microscopic and sub-microscopic form. As such, it is not amenable to recovery by conventional cyanidation. The zone of oxidised and transitional ore is developed to a maximum depth of 40 m.
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.
|Ore Reserves||Tonnage, Mt||Gold grade, g/t||Silver grade, g/t||Copper grade, %||GE grade, g/t||Gold, Koz||Silver, Moz||Copper, Kt||GE, Koz|
|Mineral Resources||Tonnage, Mt||Gold grade, g/t||Silver grade, g/t||Copper grade, %||GE grade, g/t||Gold, Koz||Silver, Moz||Copper, Kt||GE, Koz|
- At Albazino, in 2021, exploration activities included exploration drilling (10.6 km) along the flanks and delineation of the ore body at the southern flank of the Olga open pit. Additional Mineral Resources increased by 342 Koz to 2.2 Moz with an average grade of 4.2 g/t.
- In 2022, small-scale drilling is planned at Albazino on the northeastern extension of the Anfisa and Nadezhda zones and on Olga’s southern flank.
- Exploration activities were completed at the Talgiy section of the Urkachik area (38.9 km of drilling). A complex of engineering-hydrogeological and oriented geomechanical drilling was carried out; metallurgical studies are nearing completion. On the flanks, exploration activities were carried out to delineate and trace ore bodies down dip. The Mineral Resource estimate is 1.1 Moz of gold with an average grade of 3 g/t — an increase by 576 Koz in 2021. The initial Ore Reserve estimate is scheduled for 2022.
- At Kutyn, 28.5 km of exploration drilling and 30,900 m3 of trenches were completed. Most of the exploration work was focused on upgrading Mineral Resources categories for mine planning. Besides, the deep horizons of the primary ore body were assessed with the use of exploration drilling on a wide-spaced grid. Areas of primary ore development with ore sections suitable for underground mining have been established. Ore Reserves increased by 40% (or 325 Koz) to 1.1 Moz of gold with an average grade of 2.9 g/t. Additional MR totaled 414 Koz of gold with an average of 5.1 g/t.
- In 2022, the Company will continue to delineate free-milling ore on the flanks of the Kutyn deposit, explore deep horizons of primary ores, search and evaluate new ore bodies within the areas of promising geochemical and geophysical anomalies. Detailed drilling will be performed within the later stages of the proposed open pit area to convert Mineral Resources into Ore Reserves.
- In 2022, the Company also plans to continue lithochemical prospecting within the lower Amur region and further study the identified geochemical anomalies by drilling with small-sized equipment.