Both deposits are located in Nikolaevsky district of Khabarovsk Territory on the left bank of the Amur River. The regional city centre of Nikolaevsk-on-Amur is 45 km from Blagodatnoye and 50 km from Belaya Gora. The deposits are located 39 kilometres apart and are connected by a municipal road. The location of the assets is shown in the figure below. The Mnogovershinnoe mine is located about 70 km from Belaya Gora and 100 km from Blagodatnoye.
Belaya Gora is an active mine. The mining operations were slowed down in early 2017 and stockpiled ore was processed whilst studies were undertaken to improve operating efficiency. Blagodatnoye is located near Belaya Gora though has a different geological environment. The strategy is to mine the remaining reserves at Belaya Gora first, which are expected to be completed by 2024, then move the mining activity to Blagodatnoye which is expected to operate for a further 8 years. The main infrastructure for ore processing and tailing storage will be located at Belaya Gora, though a crusher will be installed at Blagodatnoye as the ore is much harder than the Belaya Gora ore and requires additional comminution. Ore from Blagodatnoye will be transported by on-highway trucks along a road which will comprise partly an existing municipal road and partly a new road which will be built.
Gold mineralization in the Belaya Gora deposit area was first identified at the end of the 19th century with the discovery of placers in the surrounding watercourse basins. Some exploration was conducted in the 70s and 80s, with the last detailed exploration stage undertaken between 2006-2008. Production started in 2010 with ore processed at the Mnogovershinnoe plant (some 70 km away). In 2013 a processing plant was constructed at Belaya Gora and production rates increased to planned 2.2 Mtpa. The original TEO of Permanent Conditions was prepared in 2008 and was updated in 2016.
Systematic exploration at Blagodatnoye started in 2010 with detailed exploration and drilling undertaken between 2011-2012 and again in 2016. No mining has taken place. The TEO of Permanent Condition was submitted for approval in 2018.
The genesis of Belaya Gora mineralisation corresponds to the same name extrusion which is developed east from the deposit. The mineralisation is hosted by volcanogenic and volcanoclastic rocks which been altered hydrothermally and transformed into secondary quartzites.
Three mineralisation zones have been defined at the deposit: Stockwork, Pologaya and North-East. The Pologaya zone has already been mined out.
Mineralization has a veinlet-disseminated, pocket character and is associated with quartz veinlets and veins. Gold distribution is extremely irregular and enriched areas are sporadic and unrelated to each other.
Grain size distribution analysis of technological samples showed that native gold in ores is distributed non-uniformly, and is mainly represented by -0.25+0.74 mm size with individual grains up to 0.8 mm.
The ore texture and structure are similar for all zones while Pologaya and North-East ores are dominated by kaolinite and smectites due to more active hypergenesis processes.
The deposit is located in the monoclinically lying tuffs and tuff-sandstones situated in the western exocontact zone of the Gyrmansky granitoid massif, which experienced low-intensity but widespread hornfelsing.
Mineralization is represented by several joined ore bodies. The location of these bodies is controlled by:
- A series of sub-latitudinal tectonic structures, which often transfer into cleavage zones;
- West-north-west faults which apparently feather the sub-longitudinal fault
Mineralisation is presented by stockworks. Veinlets that form these stockworks are mostly smooth, from a millimetre to few centimetres thick. The amount of veinlet-ore material varies from a trace to rarely more than five percent. The shape of bodies is close to isometric or is elongated with sub-vertical dip. The vertical span of mineralization is 250-280 m. The gold of the deposit is fine with 80% grains less than 0.071 mm.
The official resource estimate for Belaya Gora deposit was performed in accordance with GKZ (State Committee for Resources) methodology and approved in 2016. Resources with gold grades greater than 0.3 g/t within the pit were classified as both On-Balance and Off-Balance. Resources outside of the pit were classified as Off-Balance. Minimum mineralization thickness was 5 m, maximum thickness of waste interlayers was 5 m. The approved resources amounted to 12.1 Mt of ore with average grade of 1.89 g/t.
The previous Mineral Resource Estimate prepared in accordance with the JORC Code was estimated by Micromine in 2010 at 14 Mt of ore with average grade of 2.2 g/tforthe Stockwork zone and 1.3 Mt at the average grade of 3 g/t for the Pologaya zone.
A source: PreFeasibility Study for Belaya Gora and Blagodatnoye Gold Project 2018 (SRK Consulting (Russia) Ltd.)