All about Siberian gold: deposits, where and how it is mined today + history of the gold rush

Currently, the bulk of gold in the world (and in Russia) is mined from primary deposits (in the Irkutsk region, almost all gold is still extracted from placers). The gold reserves of our country were estimated as follows: in 1953 - 2050 tons, in 1995 - 122, in 1998 - no more than 90 tons. This is very little for Russia, which is rich in gold resources. For comparison, we can say that gold reserves in Germany are now approximately 3.7 thousand tons, in the USA - about 8 thousand tons, in South Africa - 33 thousand tons (38% of world reserves).

Gold Rush in Siberia

Thanks to the works of Jack London, the whole world knows about how gold miners mined precious metal in America. However, it was in Siberia that the real Gold Rush began in the first half of the 19th century.

Until the 19th century, the Russian Empire had almost no mines of its own, increasing its gold reserves through warfare and trade. Although back in the 17th century, mounds and burial grounds with numerous gold decorations were found in Siberia. By decree of Peter I, a collection of similar products was collected, which is located in the Kunzkamera.

In 1812, a decree was issued allowing representatives of certain classes to mine precious metals. One of the first who decided to organize an expedition to Siberia were the merchants Popov. Their attention was attracted by the hermit Yegor Lesnoy.

According to one version, the Old Believer Yegor, nicknamed Lesnoy, lived with his pupil near the Sukhoi Berikul River. Now this is the Kemerovo region. The hermit more than once found large gold nuggets, but kept the fishing location a secret.

According to legend, the Popovs sent their people to Yegor to show him where to look for the deposits. Then they decided to meet him in person. However, by the time they arrived, the owner was strangled. In 1828, Andrei Yakovlevich Popov submitted an application to develop deposits on the Berikul River. Perhaps the place was indicated by a pupil of Yegor Lesnoy.

Later, the Popovs discovered several more gold deposits in the Kuzbass and Novosibirsk region, in the basin of the Ob, Tom, and Yenisei rivers.

In 1820, the Gold Rush began in Siberia. Russia came out on top in the world in gold mining, most of which came from the Ural and Siberian deposits. From 1819 to 1861, about 36 pounds of precious metal were mined, which is almost 590 tons.

The rapid development of the gold mining region contributed to the growth of cities and the population of Siberia. Trade turnover has increased significantly. For example, if in the 1930s the region purchased bread worth 350 thousand rubles, then by 1850 it was worth five million. Diligent artels needed food, clothing, horses, and equipment. This contributed to the development of the region's economy.

By the end of the 19th century, the industry began to decline in development. Wealthy gold miners invested in other industries or moved them out of the region. Old sources dried up, and new ones were not developed.

Many of the richest earners went bankrupt due to poor business management and unreasonable spending. There were legends about the carousing, drunkenness, and ostentatious luxury of rich gold miners. So, for example, N.F. Myasnikov ordered business cards made of pure gold. And Gavrila Masharov had a medal made of precious metal weighing 8 kg, with his own portrait, for which he received the nickname “Taiga Napoleon”. He built a huge house in the taiga with glass greenhouses in which exotic fruits grew.

Even the mines he discovered in the Yenisei taiga did not cover such expenses; as a result, Masharov was declared bankrupt and died in poverty.

Prospects for gold mining in the Irkutsk region

The mineral resource base of gold in the Irkutsk region is represented by ore and placer deposits located in the Baikal (Lensky gold-bearing region), East Sayan provinces and in the Pribaikalsky (Verkhnelensky) gold-bearing region (Fig. 1). Gold mining is the leading mining activity in the region and provides 50% of the total volume of mined mineral raw materials in value terms. The Irkutsk region is a leader in the extraction of placer gold, but the development of ore deposits is just beginning. More than 95% of the region’s gold is mined in the Bodaibo region; over 150 years, about 1,200 tons of the recorded metal have been extracted from its depths.

Until 2000, 10.2-10.4 tons of gold were mined in the Bodaibo region, mainly from alluvial deposits; over the last 9 years, production has stabilized at 14.5-14.9 tons, more than 11% of all-Russian gold production. Despite the high percentage of placer gold mining, recently the main attention in the region has been focused on the development of gold deposits; it is planned to increase gold production by 3-5 times.

At the end of 2009, the region ranks 5th in Russia in gold mining, behind the Krasnoyarsk Territory, Chukotka Autonomous Okrug, Amur Region, Sakha-Yakutia, and slightly ahead of the Magadan Region and Khabarovsk Territory. In 2009, 14.7 tons of gold were mined (+1.7% compared to 2008), including ore gold - 4.38 tons (-9.5% compared to 2008), alluvial gold - 10.39 tons (+7.2% compared to 2008). In 2010, it is expected that 14.9 tons of gold will be mined, including 5.1 tons of ore gold and 9.8 tons of alluvial gold. (According to Advis.ru with reference to PRIME-TASS)

In the future, gold mining will be concentrated on the development of ore deposits in the Bodaibo region, where the largest reserves in Russia are concentrated, including the unique Sukhoi Log deposit. With the commissioning of a mining and processing plant at this deposit, the Irkutsk region will take a leading position among the gold-mining regions of Russia.

The history of gold mining in the Lensky region begins in 1846, when in the valley of the river. Khomolkho, 30 km northeast of Sukhoi Log, the first gold placers were discovered (Wood, Popov, 2006). In the 1860s, rich alluvial gold deposits were found in many nearby areas, including small valleys on the northern and southern sides of the Sukhoi Log hill, called Radostny, Zorinsky, Sukhoi Log. More than 30 tons of gold were mined from these three alluvial deposits between 1863 and 1900. On the crest of the watershed, where numerous outcrops of large gold-bearing quartz veins were known, the Sergievsky mine was declared in 1886, and the Utesisty mine in 1894. The main objects for the first searches for gold during 1899-1904. There were these and other quartz veins, from which about 1 ton of gold was extracted during prospecting, but its extraction turned out to be difficult, and the work was stopped.

In the 1960s, geologist V.A. Buryak, based on the geochemical anomaly and gold content in rock samples from Sukhoi Log, suggested the existence of gold-bearing sulfide-disseminated ores. The first wells, drilled in the spring and summer of 1961, made it possible to detect gold-bearing sulfide mineralization at depth, which confirmed the forecast of V.A. Buryak. Intensive exploration of the deposit began in the fall of 1971 and was completed at the end of 1977.

As a result, 209.6 km of diamond core was obtained, extracted from 846 wells; passed: 11.7 km of underground workings (adits No. 1 and 2), 1.546 km of which were passed through ore, 110.3 km of ditches. In addition, 13,000 furrow samples, 3 process samples of 150, 800 and 980 tons were taken, many tens of thousands of gold assays were carried out, as well as many other analyzes for various purposes. The data is stored in multi-volume reports and provides a very detailed database for this field.

Rice. 1.

To prepare this deposit for exploitation, as can be seen from what was written above, huge amounts of money were spent, new mining villages and roads were built, and all of this has recently been destroyed and degraded.

Vladimir Afanasyevich Buryak wrote: “Sukhoi Log is the largest gold deposit not only in Russia, but also in the World. This is the national treasure of our country. When licensing it, one must be guided not only and not so much by the interests of today, but mainly by the future of our economy. This gold mining giant can decisively determine the volume of gold mining in the country.”

A feasibility study (TES) and a project of permanent conditions for the Sukhoi Log gold deposit were developed in 1975-1977. VNIIprozoloto together with IRGIREDMET. The reserves of the deposit were approved by the USSR State Reserves Committee in 1977 (ore - 383.5 million tons, gold - 1038.4 tons, average gold content - 2.71 g/t). Geological exploration work (GRR) at the field continued until 1992. In 2006-2007. TsNIGRI, on the instructions of Rosnedra, carried out a comprehensive technological and geological-economic revaluation of the Sukhoi Log gold deposit (Migachev et al., 2008).

The technical and economic indicators of the feasibility study of conditions developed in 1977, in comparison with the indicators obtained during the revaluation of the field in 2007, have undergone significant changes. Thus, the volume of ore and metal used to justify the feasibility study in 2007 increased by 2.6 and 1.9 times, respectively (Table 1); the annual production capacity of the enterprise for ore mining increased from 12 to 34 million tons (2.8 times), for metal production - by 2.3 times; the payback period for funds invested in the construction of the enterprise decreased from 26 to 8.7 years; the level of profitability of production assets increased from 2.3 to 22.3% (Migachev et al., 2008).

State and problems of SME gold in the Irkutsk region

Ore gold. In terms of ore gold reserves, the region is in first place in the Russian Federation, thanks to the presence of the unique Sukhoi Log deposit (Fig. 2, Table 1). In addition to this giant, in the Bodaibo region, 6 more medium and large deposits of gold-quartz-sulfide veinlet-disseminated type with low contents (2.5-3.5 g/t) similar to Sukhoi Log were identified - Vysochaishe, Zapadnoe, Nevskoe, Verninskoe , Devil's Trough, Ykanskoe. The first three are already being developed; preparatory work is underway for the rest. The total reserves for these deposits are 185.4 tons and upon completion of detailed exploration they can increase 3 times.

Gold-quartz (vein) type reserves are concentrated in 6 deposits and total 15.5 tons, but are characterized by higher (4.5-12.0 g/t) contents. Two of these deposits – “Pervenets” and “Yubileinoe” – are being prepared for development, and geological exploration work is underway at 4.

The overall potential of the Irkutsk region significantly exceeds proven reserves. The officially tested predicted resources of ore gold are unique in quantity and, according to various estimates, range from 5 to 10 thousand tons. The majority (80%) of the predicted resources of ore gold are located in the Lensky gold-bearing region, of which the gold-quartz type accounts for about 30%, and the gold-quartz-sulfide type – 70%.

The Lensky gold-bearing area is located on the territory of the Bodaibinsky district of the Irkutsk region (Fig. 1). The area belongs to the sparsely populated northern territories. The bulk of the population is employed at gold mining sites and auxiliary industries. The region is characterized by a difficult geographical and economic situation, uncomfortable living and working conditions. The nearest railway station Taksimo is located on the BAM highway, 355 km from the Sukhoi Log field and is connected to it by the federal highway Taksimo - Bodaibo (220 km) and the regional highway Bodaibo - Kropotkin - Sukhoi Log (135 km). The federal road operates all year round, but has not been put into operation due to incomplete construction; regional - needs radical reconstruction. With the increasing volumes of precious metal production in the region, a persistent shortage of electricity is developing. Since December 22, 1961, the Mamakanskaya hydroelectric power station has been producing industrial electricity in the region, with a capacity of 86 thousand kW. For many years, the Mamakan hydroelectric station met the energy supply needs of the region, generating 310-330 million kW-hours per year. With the launch of new walking excavators, a shortage of electricity began to be felt again, in order to reduce its severity, in March 1989 the 110 kW Taksimo - Mamakan line was put into operation. The area received a stable power supply through connection to the unified energy system of Siberia through the BAM power grid. Its own energy capacities (Mamakan hydroelectric power station and small diesel power plants with a total capacity of 5-6 MW) are not able to fully meet the needs of the region.

Thus, the development of the Sukhoi Log field is directly related to the construction of the Telmamskaya hydroelectric power station on the Vitim River. All necessary preparatory work at the confluence of the Telmama River and the Mamakan River was completed, but in 1993, construction of the station was stopped due to the cessation of funding.

Rice. 2.

Table 1.

It should be noted that in the area of ​​the Sukhoi Log deposit, deposits of construction materials and fresh groundwater have been explored, which can be used in the construction and operation of the mining and processing plant.

The Lena gold-bearing region is composed of Proterozoic carbonate-terrigenous rocks, crushed into complex large folds. The main ore zones of the region are confined to synclinal structures, which include the Khomolkhino-Iligirskaya ore zone, where Golets Vysochaishy is located and the Khomolkhino ore field with an area of ​​240 km2; Verninsko-Nevskaya ore zone, Sukhoi Log, Zapadnoye, Verninskoye and other deposits, within the eastern part of which the Leprindo ore occurrence with an area of ​​40.5 km2 is located. In the north of the region, the Artemovsky gold ore cluster has been identified, including the Chertovo Koryto deposit and a number of occurrences. In the southern part of the region, the Uryakh ore zone is distinguished.

The most promising areas are the Kevakhtinskoye and Khodokanskoye ore fields in the Patomo-Nechersky ore district, Marakanskoye, Svetlovskoye, Zheltukhovskaya and a number of others in the Bodaibinsky ore district, Uryakhskoye and Mukodekskoye in the Muya ore district. It is expected to identify both large and medium-sized objects.

20% of the resources are concentrated in the East Sayan gold province, but here the extremely low level of exploration of the province for ore gold in the presence of favorable structural and mineralogical criteria gives reason to hope for a significant increase in the potential of the region due to this territory. The increase in resources can be achieved both through the identification of new objects of the gold-quartz and gold-sulfide-quartz type, and through gold reserves in complex deposits, which are not taken into account by the forecast estimate.

Placer gold. In terms of balance reserves of alluvial gold (152.1 tons), the Irkutsk region is a leader among the regions of the Russian Federation and their quantity is sufficient to ensure the existing level of production for about 10 years. The main reserves (more than 95%) have been explored in the Lensky gold-bearing region, the rest are located in the Eastern Sayans and in the Baikal region. The main share of placers in the Bodaibo region is represented by relatively small objects with reserves of less than 700 kg, although several placers with reserves of up to 5-7 tons are also being mined. Prospecting and exploration work for placer gold, the predicted resources of category P1 of which are estimated at 135 tons, should ensure continuation work for another 12-15 years. In the meantime, with total proven reserves of gold in alluvial deposits of about 150 tons and mining of 10-11 tons, the supply is limited to 9-10 years. To maintain the volume of gold production from placers in the period until 2030, it is necessary to ensure an increase of 220 tons of placer gold.

Basically, alluvial gold reserves are characterized by high quality, which allows them to be mined with high profitability. However, a characteristic feature is the disproportion between the structure of production and the structure of reserves. 86% of the metal is mined by open-pit mining, and reserves for this type are 52%. In this regard, the increase in reserves is almost 100% due to the open separate method; moreover, part of the dredged reserves is transferred to reserves for the separate method. There is also a clear tendency for SMEs to operate, accompanied by a deterioration in the quality of raw materials. Cases of bringing into production off-balance reserves and host rocks with substandard contents are becoming more frequent.

Alluvial gold resources are sufficient to reproduce reserves at the current rate of gold mining over the next 10 years. Of the total forecast resources, 25% corresponds to category P1, 12% to category P2 and 63% to category P3. The overwhelming majority of resources (94%) are located in the Lensky gold-bearing region, in the East Sayan region - 5% of the resources, in the Pribaikalsky region - about a percent.

In the East Sayan Province, the resource potential can be realized through the discovery of solid alluvial placers in watercourses draining gold fields and nodes. An extremely insignificant amount of geological exploration work has already revealed placer occurrences near two ore clusters with P1 category resources of 250-500 kg, and the general prospects of each of these nodes can be estimated at 3-5 tons of metal.

Thus, in the coming decades, alluvial gold production in the Irkutsk region will be stable with a tendency towards a gradual decrease due to the depletion of its SMEs. An influx of investment is expected in the development of rich placer gold sites with difficult mining conditions and technogenic placers.

At the same time, the development of ore deposits will lead to an increase in the production of indigenous gold and an increase in the volume of gold production in general. For primary gold, intensification of work and, accordingly, investments is necessary for all groups of deposits - from small to unique and from those prepared for exploitation to those predicted.

“Long-term state program for the study of subsoil and reproduction of the mineral resource base of Russia based on the balance of consumption and reproduction of mineral raw materials” (Approved by order of the Ministry of Natural Resources of the Russian Federation dated 06/08/2005 N 160)

It is planned to sell 470 tons of resources of primary gold of categories P1+P2, as well as to obtain an increase in reserves of categories C1+C2 in the amount of 150 tons. For alluvial gold, 30 tons of resources of category P1 will be sold and 80 tons of reserves up to categories C1+C2 will be explored. However, the parameters laid down in the Long-Term Program must be adjusted, taking into account the latest data on the increase in reserves due to recalculation at the Sukhoi Log field.

The main gold deposits of the Irkutsk region

The Sukhoi Log gold deposit is located in the central part of the Lensky gold mining district, approximately 850 km from Irkutsk (Fig. 1). The deposit is located within the Krapotkinsky gold ore cluster and is localized among the host rocks, which are represented by Upper Proterozoic marine sandstones, carbonate shales and phyllites, metamorphosed to low degrees of greenschist facies, in the peripheral part of the main Akitkan deposit chat belt. A sheet ore body with dispersed pyrite mineralization is located in the axial zone of an inclined anticlinal fold. Ore bodies are identified solely on the basis of sampling.

The richest high-quality ores (4.9 g/t Au) are located in pyritized layers of black shale (Fig. 3), especially at the places of their intersection with the axial zone of the fold, where they form two extended cylindrical zones, the so-called ore columns, p located along the slightly submerged crest of the anticline.

Rice. 3. Vein ores of the Sukhoi Log gold deposit

The protruding part of this anticline, more than 3 km long, extends from east to west and then plunges in a direction of approximately 10° to the northwest. Ore mineralization is quartz-pyrite-gold ± carbonate association (Fig. 3) with an admixture of base metals and platinum group metals. Pyrite is widespread in black shales throughout the deposit (between 2 and 5%) and in smaller quantities is found in a dispersed form in the form of a halo around the ore body. The outer portions of this orebody and the adjacent mineralized aureole contain high purity gold (900-920), while gold from the clustered and veined pyrite most abundant in the inner productive zone is of lower purity (840-880). The balance reserves of gold for the deposit amounted to 930.35 million tons of ore and 1952.9 tons of gold with an average content of 2.1 grams per ton (see Table 1). Off-balance reserves of gold for the deposit amounted to 798.8 tons. The total resource potential of the Sukhoi Log deposit (reserves + resources P1) is 2956.4 tons of gold and 1541 tons of silver. In addition to reserves at the deposit, the predicted resources of gold category P1 were estimated in the amount of 205 tons. The predicted gold resources of the ore field were also assessed for categories P1 (810 tons) and P2 (210 tons) with an average gold content of 0.59 g/t, including 406 and 158 tons respectively with a gold content of 1.15 g/t.

The Zapadnoye deposit is located within the largest gold mining region in Russia, the Lensky gold mining region, identified as an independent zone within the main gold-bearing mineralized zone of the Sukhoi Log ore field of the Krapotkinsky ore cluster, covering the western flank of the ore field. The Zapadnoye deposit is located 1.5 km from Sukhoi Log, the type of ore is similar to Sukhoi Log.

In 2009, about 0.8 tons of gold were mined. The license for exploration and production belongs to OJSC Polyus-Zoloto, the largest gold mining company in Russia. Although the Zapadnoye deposit is considered an independent object, the studies carried out by IGEM RAS in 2006-2007 allow us to assert that this is only the eastern continuation of the Sukhoi Log ore deposit. This is indicated by the same spatial position (strike, dip) of both gold-bearing quartz-sulfide veins and later quartz veins bearing mineralization, as well as the identity of their mineralogical composition. Reserves of the Zapadnoe deposit are 12 tons. along strike 300 m, thickness 50-60 m. Avg. sod. 2.7 g/t.

The Golets Vysochaishy deposit is located 40 km north of the village. Kropotkin and 175 km from Bodaibo. The subsoil user of the deposit is OJSC Vysochaishy. He also owns licenses for the Khomolkha ore field and for the Leprindo ore occurrence. Commercial ores include ores with a gold content of 2.4 g/t and higher. In 2008, the State Reserves Committee reported reserves for the field as 68 tons, with a cut-off grade of 0.8 g/t. Currently, the deposit is being developed by two quarries - Western and Eastern - which will eventually be combined into one.

The Chertovo Koryto deposit is located in the northern part of the Bodaibo region, 185 km from the city of Bodaibo (Fig. 1). The deposit was discovered in 1962. In 2004, the license to develop the deposit was acquired by the Polyus Group. The reserves of the deposit in category C2 to a depth of 30-60 meters amounted to 11 tons of gold. The predicted resources of the deposit are determined to be 226 tons of gold. According to the auditors' report, the deposit's Proved and Probable ore reserves amount to 43.61 million tons of ore with a gold content of 1.83 grams per ton and 79.96 tons of gold (2.6 million ounces). The measured and indicated mineral resources of the deposit amounted to 50.49 million tons of ore grading 1.84 grams per tonne and 92.95 tons of gold.

The Mukodekskoye deposit is located in the southern part of the Mamsko-Chuysky administrative district in the Mamskoye ore-placer cluster (Fig. 1). Its predicted resources in categories P1 and P2 are 200 tons of gold. In 2004, the license to develop the field was acquired by the Polyus Group. Currently, organizational and geological exploration work is underway at the deposit in order to assess industrial grade gold reserves.

The Verninskoye deposit is located in the central part of the Bodaibinsky district, 125 km from Bodaibo, 6 km from the village. Kropotkin and 15 km from the Sukhoi Log deposit (Fig. 1). The nature of the mineralization is similar to the large Sukhoi Log deposit, but is inferior to it in scale. The Pervenets deposit is located 250 m south of the Verninskoye deposit and is geologically part of it. In 1999, gold reserves at the Verninskoye and Pervenets deposits in categories C1 + C2 were approved in the amount of 80 tons with an average content of 2.3 g/t, predicted resources in categories P1 + P2 - in the amount of 185 tons. In 2004, the license to develop the field was acquired by the Polyus Group. The resource potential of these deposits, according to the company, is 350 tons. The company is carrying out geological exploration at the deposit in order to increase reserves of industrial categories and determine the most economically profitable ore processing scheme. The Zapadnoye, Pervenets and Verninskoye deposits form a single ore cluster with significant prospects in terms of further reserve growth.

The Medvezhiy gold mining site is located in the Bodaibinsky district of the Irkutsk region, within the Kropotkinsk ore cluster. Near the licensed subsoil area there are gold deposits Verninskoye and Pervenets (developed by subsidiaries of Polyus Gold) and Nevskoye (subsoil user - Druza LLC). The resource potential of the western part of the site is 7 tons of ore gold, its area is 7 sq. km. Resources of the eastern part are 5 tons, area is 16 km2.

Zheltuktinskaya and Verkhne-Kevaktinskaya promising areas are located in the north of the Bodaibinsky district of the Irkutsk region and are part of the Artemovsky ore field. The Zheltuktinskaya and Verkhne-Kevaktinskaya promising areas are directly adjacent to the license area for geological exploration and gold mining at the Chertovo Koryto deposit, acquired by the Polyus Gold group at the end of 2004. The predicted resources of the Zheltuktinskaya and Verkhne-Kevaktinskaya areas of category P2 are 90 tons.

Gold mining site "Babushkin". Holder of a license for geological study, exploration and production of ore gold in Moscow (affiliated with NK Eton-Oil). The Babushkin site is located in the Bodaibinsky district of the Irkutsk region, 90 km from the city of Bodaibo and 310 km from the Taksimo railway station. The nearest settlement for the site is the village of Artemovsky, which is located 20 kilometers from the licensed area. Plot area – 164 sq. km. The resource potential of ore gold is estimated at 16 tons.

The Ostantsovy site is located in the Bodaibinsky district of the Irkutsk region, 120 km from Bodaibo and 340 km from the Taksimo railway station. The nearest settlement for the site is the village of Marakan, which is located 1.5 kilometers from it. The owner of the license for geological study, exploration and mining of ore gold is OJSC Severstal. The area of ​​the license area is 121 square meters. km. The resource potential of ore gold is estimated at 18 tons.

The Uryakh ore field is located in the Bodaibo district, 180 km from the city of Bodaibo, on the border with Buryatia and the Chita region. The predicted resources of ore gold in categories P2+P3 are estimated at 100 tons. The owner of the license for geological study, exploration and mining of ore gold is OJSC Severstal.

The Longitudinal site is located in the Bodaibinsky district of the Irkutsk region, 45 km from Bodaibo and 265 km from the Taksimo railway station. The nearest settlement for the site is the village of Artemovsky, which is located two kilometers from the licensed area. The owner of the license for geological study, exploration and mining of ore gold is Kopylovsky LLC, a subsidiary of Tardan Gold LLC (Kyzyl, a subsidiary of the Swedish Central Asia Gold). The area of ​​the license area is 141 square meters. km. The resource potential of ore gold is estimated at 18 tons.

Kopylovsky section. Kopylovskoye reserves in the C1+C2 category are 5 tons of gold, predicted resources are 40 tons, with an average gold content of 3 g/t. Since receiving the license, Kopylovskoye LLC has not been able to obtain commercially pure gold from the ore of the deposit, although it examined the ore at one of the gold extraction factories in the region.

The Voznesensky site is located in the Bodaibinsky district of the Irkutsk region, 90 km from Bodaibo and 310 km from the Taksimo railway station. The area of ​​the license area is 39 square meters. km. The resource potential of ore gold is estimated at 8 tons.

Ozherelye and Ykanskoye deposits. At the beginning of 2007, Zoloto Resources (Canada), through its subsidiary Baykal Gold, acquired for $10 million a 51% stake in ML LLC, which is developing the Ozherelye and Ykanskoye gold deposits, located in the Irkutsk region near Sukhoi Log. . In 2007-2010, the Canadian investor planned to invest $12 million in their additional exploration. However, in 2009, he assigned the license to OJSC Vysochaishy. “ML” received licenses for the development of the Ozherelye and Ykanskoye deposits in 2006 based on the discovery; previously it owned licenses for the study of these areas. The total reserves of deposits in categories C1+C2 are about 5 tons, resources - 17 tons.

The Khodokansky site is located in the Bodaibinsky district of the Irkutsk region. The area of ​​the licensed plot is 18.4 square meters. km. The reserves of the site are estimated at 30-70 tons. According to the terms of the auction, the license period is 25 years. The Orbis Capital company must complete exploration within six years from the date of state registration of the license, and within seven years prepare a project for the development of the site. Over the next 7.5 years, construction of a mining and processing plant should begin, and after 8.5 years, industrial gold mining should begin. In nine years, it is expected to reach the design capacity of 1 ton of gold per year. The predicted gold resources (tons) are, according to expert estimates as of October 1, 2004: category P1 - 2 tons, category P2 - 15 tons, category P3 - 13 tons.

Prospects for the development of gold mining in the Irkutsk region

The creation of mining centers (clusters) of economic development (CED) of federal significance based on a large raw material base is planned in the Yana-Kolyma and Bodaibo geological and economic regions. Such centers have important socio-economic and geopolitical significance. The development of the resources of these two clusters alone will allow the annual production of up to 150 tons of gold. When can giant gold mining enterprises be built and reach full capacity?

The political will of the leadership of the USSR and the entire power of Sredmash of the USSR was required for the accelerated commissioning of the Muruntau Mining and Processing Plant, comparable in gold production to the planned mining and processing plants at the Sukhoi Log and Natalkinskoye deposits. New cities grew in the Kyzyl-Kum desert, supporting infrastructure was created, personnel were trained, the largest gold processing plant in the country and in the world was built, and even a bus service was organized through its territory. Construction continued in stages and took more than 20 years. How are things going in our capitalist, market times in Russia? Endless meetings continue, programs, projects are developed, strategies are adopted. However, the construction of large mining and processing plants in the Irkutsk region is not yet visible. This is evidenced by Table 2 below.

Table 2. Dynamics of gold production by leading enterprises of the Irkutsk region in 2001-2007.

(Brayko V.N., Ivanov V.N., Results of the work of the gold mining industry in Russia in 2007 and its prospects for the coming years Mineral resources of Russia. Economics and management, 3-2008)
∗Lensk Gold Mining Company LLC (LZRK) was created in 2004 as part of the structuring of the assets of CJSC Polyus.
∗∗In 2006, Druza LLC acquired A/s Sibir LLC and, together with Daksib LLC, formed gold mining assets under common management. In short, the market is in no hurry to develop the gigantic but poor gold deposits in Russia. It seems that large companies, which have distributed among themselves almost all of the country’s SMEs, despite loud statements, are not interested in developing this SME.

Lenzoloto OJSC (Polyus Gold OJSC) plans to maintain annual gold production at the level of 5-6 tons for the next 5 years.

Lensk Gold Mining Company LLC (Polyus Gold OJSC) is implementing a project for the development of the Verninskoye deposit. The project provides for ore processing in the amount of 1.6 million tons in 2010, and 2.2 million tons annually starting from 2011. Gold output in 2010 will be 4.8 tons, and from 2011 - 6.4 tons per year.

OJSC “Vysochaishy”, a dynamically developing company, in 2007 crossed the production line of 3 tons and entered the top ten leading gold mining companies in Russia.

In 2010, taking into account production by subsidiaries, it intends to overcome the 5-ton mark.

In conclusion, we note that in order to stabilize Russian gold mining for the long term and due to the favorable conditions on the world market (the price for 1 gram of gold in recent years has increased 2.5 times and reached $30), there is an urgent need to develop large reserve deposits; deposits of the Bodaibo region - Sukhoi Log, etc.

With favorable developments in the field of gold mining (launch of the country's largest mining and processing plant at the Sukhoi Log deposit), the Irkutsk region by 2030 can reach a production level of about 50 tons of gold.

A.V. Volkov – IGEM RAS

Published in the magazine “Gold and Technology” No. 3(10)/October 2010

How gold was mined in the past

The precious metal was mined in the gold-bearing rivers of Siberia: tributaries of the Ob, Yenisei and Tom. Until the mid-19th century, the method of obtaining raw materials was primitive: prospectors washed river sand. The lighter grains of sand were washed away, and the golden grains, being heavier, remained at the bottom. This is how large nuggets were found. The largest, weighing more than 36 kg, was found in 1842 M.N. Syutkin.

They tried to mechanize the process. For example, in 1875, the merchant Pakulev invented a machine that washed sand. At the same time, tests were carried out on the use of a mechanism that opened the rock. The first attempts were successful, but subsequent design imperfections prevented the use of the invention.

In eastern Siberia, since 1860, a huge machine, the Peskovoz, was used, resembling a conveyor belt. At the same time, water lifting technology was invented and used at the Olekminsky gold mine.

Deposits of Siberia

In the Irkutsk region

The Irkutsk region ranks first in gold mining among all regions of Russia. The largest Sukhoi Log deposit and a number of smaller mines are located here.

Sukhoi Log

Sukhoi Log contains a significant part of the gold reserves of Siberia.

Development of the field began in the 60s of the last century in the eastern part of the region, after scientists studied geomagnetic anomalies in the region and samples of local rocks. Preparing the mine required large investments, but the state's investment has fully paid off. Sukhoi Log still remains one of the most promising gold mining centers in the country.

Bodaibo district

90% of the precious metal is mined in the Bodaibo region. In the 90s, about 10 tons of placer gold were mined here. In the future, the amount of gold mined will increase due to the development of ore deposits.

Large centers include:

• Western, located in the Badaibo region, the structure of the rock is similar to Sukhoi Log;
• Verninskoe;
• "Black Hoof" According to scientists' research, 226 tons of Siberian gold can be mined here.

Altai Gold

On the territory of the Altai Territory there are two large zones with deposits of precious metals:

• Rudno-Altai;
• Tigireksko-Belokurikha.

Gold raw materials for the royal treasury have been smelted here since the 18th century. After the revolution, the business was abandoned, despite the rich reserves of deposits. Only in the 80s of the 20th century, thanks to the work of diligent artels, the extraction of placer gold began. The volumes were small; by the 90s, 135 kg were received here annually.

It took two decades to restore the region's mining industry. Now new enterprises have been opened in the Rubtsovsky district and the mines of the Korbolikhinsky deposit. Attracting investment in the region is facilitated by data on the presence of rare elements. One of the priority areas was the Topolinsky ore field, where on an area of ​​96 sq. km. the presence of 50 tons of gold is expected.

Leno-Vitimsky gold-bearing area

The oldest gold mining area is located in the basins of the gold-bearing Siberian rivers Olekma, Chara and Vitim. The first placer gold mines were discovered in 1849, named Voskresenky and Spassky. The Pervenets ore deposit began to be developed in 1956. About 300 places of placer gold and 11 ore deposits have been identified in the region.

According to scientists, there are 4.6 thousand tons of precious metals here.

Sukhoi Log field

This gold deposit is located 140 km northeast of the city of Bodaibo. It is the largest and most unique, and not only in Russia. Its balance reserves are determined to be 1029 tons. However, the gold content in the ore is relatively low (on average 2.76 g per 1 ton of rock). The profitability of developing this deposit is also low and is associated with the organization of large-scale production (10-20 million tons of ore per year), which will require quite significant initial capital investments (for the construction of the mining and processing plant and the creation of the corresponding infrastructure), estimated at 1.5-2.0 billion dollars Such production can annually produce 25 or more tons of gold. Industrial mining of related components, for example, platinum group metals and other minerals, is also possible here.

The development of gold reserves in Sukhoi Log began in 1985. The work was carried out by the Lenzoloto Production Association of the USSR Ministry of Non-ferrous Metallurgy at the expense of government funds allocated from centralized sources. After 1992, financing was carried out exclusively from borrowed and own funds of Lenzoloto JSC and Mining.

To date, some design and survey work has been completed. The reserves of industrial categories of building stone, lime, loam, gravel, sand, soils necessary for the construction of industrial and transport infrastructure facilities, as well as water reserves for technical and economic water supply of the future mining and processing plant and the village, have been assessed. About three-quarters of the Taksimo-Bodaibo-Sukhoi Log highway has been built.

Extraction methods

The process of gold mining these days is completely mechanized. The method depends on the concentration of the mineral in the rock. An acceptable figure is 3 grams of precious metal per 100 kg of rock. If this value approaches 10 grams, the deposit is considered rich.

To process rocks, dredges are used, mining machines that can float and extract rock from the Siberian depths.

To obtain pure gold, a chemical method is used - the rock is treated with sodium cyanide, which turns even the smallest particles of gold into liquid.

Then, using a special reagent, the metal is given a solid state again. This method allows you to get good results when processing rock in abandoned mines.

Decrease in production

Since 2008, there has been a decrease in the amount of precious metal mined in Siberia. There are several reasons for this:

1. Depletion and reduction in the quality of raw materials from developed deposits.
2. Lack of qualified personnel.
3. Many small enterprises that brought in up to 50 kg of metal annually have closed.

In 2017, the amount of gold mined decreased by 10%. The same decline was observed in 2021, when the Irkutsk region lacked 2.5 tons of gold.

State of the gold mineral resource base

The mineral resource base (MRB) of gold in the Irkutsk region is represented by ore and placer deposits located in the Baikal, East Sayan provinces and the Bodaibo gold-bearing region (Fig. 3). Currently, of the total amount of gold explored in the Irkutsk region, the share of ore gold is approximately 85%, and alluvial gold is 15%. Balance reserves are concentrated in almost 300 fields, and predicted resources are estimated for more than 100 objects. In addition, isolated occurrences of gold are often observed in mountain river valleys, rock outcrops, and traps of the Siberian Platform.

Rice. 3.

Gold deposits of the Bodaibo region

Gold mining is the leading mining activity in the region and provides ~50% of the total volume of mined mineral raw materials in value terms. In terms of alluvial gold mining, the Irkutsk region is in second place after the Magadan region, while the development of ore deposits is just beginning. Until 2000, 10.2–10.4 tons of gold were mined in the Bodaibo region, mainly from placer deposits, then over the next 12 years, production remained at the level of 14.5–16 tons (more than 11% of all-Russian gold production), and in the last 5 years, its noticeable growth was observed - up to 22.6 tons (see Table 1 on p. 120). Despite the high percentage of placer gold mining, recently the main attention in the region has been focused on the development of gold deposits, from which it is planned to increase gold production by 3–5 times or more.

At the end of 2021, the Irkutsk region traditionally ranks 5th in Russia in gold production, behind the Krasnoyarsk Territory, Chukotka Autonomous Okrug, Magadan Region, the Republic of Sakha (Yakutia), and slightly ahead of the Amur Region and Khabarovsk Territory. In 2021, 22.6 tons of gold were mined, which is 2.5% more than a year earlier. Of the total volume, 49.5% is accounted for by alluvial gold, the production of which amounted to 11,196 tons, which is 2.5% more than in 2015. Mining of ore gold reached 11.4 tons (an increase of 2.6%). It is expected that gold production will remain at this level in 2017>3.

Placer gold is mined by more than 40 enterprises, the largest of which are:

• CJSC Svetly (part of OJSC Len-zo Lotto and Polyus Gold);
• CJSC Sevzoloto (part of OJSC Len Gold and Polyus Gold);
• CJSC Marakan (part of OJSC Len-Zoloto and Polyus Gold);
• CJSC ZDK Lenzoloto (part of OJSC Lenzoloto and Polyus Gold);
• CJSC Lensib (part of OJSC Len-Zoloto and Polyus Gold);
• CJSC "Dalnyaya Taiga" (part of OJSC "Lenzoloto" and "Polyus Gold").

In general, the enterprises of OJSC Lenzoloto produce about 6 tons of gold per year.
CJSC AS Vitim (an independent enterprise that is not part of OJSC Len-zoloto) consistently produces about 2 tons of gold per year.

The main ore enterprises of the Bodaibo region: 1.

OJSC "Vysochaishy" - about 5 tons.
2.
OJSC "Pervenets" (part of Polyus Gold) - 5.8 tons.
3.
LLC "Druza" - 0.5 tons.

“Long-term state program for the study of subsoil and reproduction of the mineral resource base of Russia based on the balance of consumption and reproduction of mineral raw materials”>4 in the region it is planned to sell 470 tons of resources of primary gold of categories P1 + P2, as well as to obtain an increase in reserves of categories C1 + C2 in the amount 150 tons. For placer gold, 30 tons of resources of category P1 will be sold and 80 tons of reserves up to categories C1+C2 will be explored. However, the parameters laid down in the Long-Term Program must be adjusted, taking into account the latest data on the increase in reserves due to recalculation at the Sukhoi Log field.

Placer gold

Gold placers in the Bodaibinsky district of the Irkutsk region have been developed for more than 170 years - since the mid-1840s - and still continue to generate stable income.
In terms of balance reserves of alluvial gold, the Irkutsk region is a leader among the regions of the Russian Federation and their quantity is sufficient to ensure the current level of production for about 10 years. The main reserves (more than 95%) have been explored in the Lensky gold-bearing region, the rest are located in the Eastern Sayans and in the Baikal region. The main share of placers in the Bodaibo region is represented by relatively small objects with reserves of less than 700 kg, although several placers with reserves of up to 5–7 tons are also being mined. Prospecting and exploration work for placer gold, the predicted resources of the P1 category of which are estimated at 135 tons, should ensure continuation work for another 12–15 years. To maintain the volume of gold production from placers in the period until 2030, it is necessary to ensure an increase of 220 tons of placer gold. According to the degree of remoteness of the mines from the city of Bodaibo, the gold-bearing region is divided into three parts: Near, Middle and Far Taiga. Near Taiga covers the mines of the Vitim system. Middle Taiga and Far Taiga make up the Olekma system. A unique economic center of Far Taiga is the village. Perevoz, located on the right bank of the river. Ruyi. The Middle Taiga was separated from the Far Taiga relatively recently. It covers mines located only in the upper reaches of the rivers of the Olekminsky watershed (Khomolkho, Zhui, Nygri, etc.), including in the upper reaches of rivers belonging to the Bolshoi Patom basin.

Within the Bodaibinsky district, the placers of floodplain valleys and terraces are of greatest industrial importance. They lie at a depth of one to several tens of meters, can be traced for tens of kilometers in length (with a width of 2–3 km), and are distinguished by their great thickness, sometimes reaching 30–60 m (for comparison: the thickness of the Aldan placers does not exceed 10–15 m) . The gold content in placers ranges from 2–8 g or more per 1 ton of rock. Sometimes gold is found in the form of nuggets. The mass of the largest of them exceeds 12 kg.

Basically, alluvial gold reserves are characterized by high quality, which allows them to be mined with high profitability. However, a characteristic feature is the disproportion between the structure of production and the structure of reserves. 86% of the metal is mined by open-pit mining, and reserves for this type are 52%. In this regard, the increase in reserves is almost 100% due to the open separate method; moreover, part of the dredged reserves is transferred to reserves for the separate method. There is also a clear tendency for SMEs to operate, accompanied by a deterioration in the quality of raw materials. Cases of bringing into production off-balance reserves and host rocks with substandard contents are becoming more frequent. The future of the Bodaibo region is associated with the development of placers, previously considered poor and substandard, as well as with the extraction of small and so-called “fine” gold from previously mined mines.

Alluvial gold resources are sufficient to reproduce reserves at the current rate of gold mining over the next 10 years. Of the total forecast resources, 25% corresponds to category P1, 12% to category P2 and 63% to category P3. The overwhelming majority of resources (94%) are located in the Lensky gold-bearing region, in the East Sayan region - 5% of the resources, in the Pribaikalsky region - about 1%.

In the East Sayan Province, the resource potential can be realized through the discovery of solid alluvial placers in watercourses draining gold fields and nodes. An extremely small amount of geological exploration work has already revealed placer occurrences near two ore clusters with P1 category resources of 250–500 kg, and the general prospects of each of these clusters can be estimated at 3–5 tons of metal.

Ore gold

In terms of ore gold reserves, the Irkutsk region is in first place in the Russian Federation (Fig. 4) thanks to the unique Sukhoi Log deposit (see Table 2). In addition to this giant, several medium and large deposits of gold-quartz-sulfide veinlet-disseminated type with low contents (1.5–3.5 g/t) similar to Sukhoi Log with low contents (1.5–3.5 g/t) have been identified in the Bodaibo region - Vysochaishe, Nevskoe, Verninskoe, Ykanskoe, Ugakhanskoe, Krasnoye, Uryakhskoye, Chertovo Koryto, etc. (Table 3). The first four are already being developed (Table 3); preparatory work is underway for the rest. The total reserves for these deposits are 185.4 tons and upon completion of detailed exploration they can increase 3 times.

Rice. 4.

Distribution of indigenous gold reserves by constituent entities of the Russian Federation

Table 3.

Status of SMEs of ore gold in the Bodaibo region as of 01/01/2017 (Source: according to company websites)
*Developed deposits.
**Deposits being prepared for development. Gold-quartz (vein) type reserves are concentrated in 6 deposits and total 15.5 tons, but are characterized by higher (4.5–12.0 g/t) contents. Two of these fields, Pervenets and Yubileinoye, are being prepared for development, and geological exploration work is underway at 4 of them. The overall potential of the Irkutsk region significantly exceeds proven reserves. The officially tested predicted resources of ore gold are unique in quantity and amount, according to various estimates, from 5 to 10 thousand tons. The majority (80%) of the predicted resources of ore gold are in the Bodaibo gold-bearing region, of which the gold-quartz type accounts for about 30%, for gold-quartz-sulfide type - 70%.

The most promising areas are the Kevakhtinskoye and Khodokanskoye ore fields in the Patomo-Nechersky ore district, Marakanskoye, Svetlovskoye, Zheltukhovskaya and a number of others in the Bodaibinsky ore district, Uryakhskoye and Mukodekskoye in the Muya ore district. It is expected to identify both large and medium-sized objects.

20% of the resources are concentrated in the East Sayan gold province, but here the extremely low level of exploration of the province for ore gold in the presence of favorable structural and mineralogical criteria gives reason to hope for a significant increase in the potential of the region due to this territory. The increase in resources can be achieved both through the identification of new objects of the gold-quartz and gold-sulfide-quartz type, and through gold reserves in complex deposits, which are not taken into account by the forecast estimate.

Reaction from abroad

Russia's rich resources attract foreign investors. So in June 2021, Prime Minister D. Medvedev signed an agreement with a Chinese company to develop the Klyuchevskoye field in Transbaikalia. The Chinese partners plan to invest $500 million in the enterprise for the extraction of gold and other precious metals, providing 700 jobs directly in production and about 1,500 jobs in related industries. The project also included Indian.

Gold of the Krasnoyarsk Territory

The Krasnoyarsk Territory is a gold-bearing region of Russia with a total gold production per year of about 70% of the total Russian volume. It was the Krasnoyarsk Territory that brought 60 tons of indigenous (nugget) gold and almost 6 tons of placer gold to the Russian treasury in 2021. Geological exploration here is expanding every year, new deposits are being found and gold mining is growing.

In total, there are three main gold mining areas in the Krasnoyarsk region:

• Karatuzsky and Kuraginsky districts in the south of Siberia - there are very few gold deposits left here, the main deposits are completely worked out.
• The North Yenisei region is the main gold-bearing source in Siberia.
• Taimyr - 2-3% of its subsoil has been studied, so the potential, according to experts, can be very significant.

In general, there are 300 deposits and promising explored places in the Krasnoyarsk Territory, which contributes well to the development of the Siberian hinterland.

Real state of affairs

Currently, the main enterprise that produces gold in the Irkutsk region and Krasnoyarsk Territory is Polyuszoloto. It is engaged in the development of ore and placer deposits in the Vitim River basin.

Small enterprises in Siberia have been closing, unable to withstand competition since 2008. In addition, old gold deposits are being depleted, and the search and development of new ones requires the use of modern technologies and large investments.

Brief outline of the history of gold mining development

The first large gold placers in the Irkutsk region were discovered by gold miner Gavrila Masharov not in Bodaibo, but in the Eastern Sayan mountains, in the river system.
Biryusy (in 1836). Three years later, gold was found on the western coast of Lake Baikal (1839). And only in 1846 placers were discovered in the Bodaibo region, in the upper reaches of the river. Khomolkho, and then in the river basin. Vitim - the famous “Sullen River”, sung in the novels of Mamin-Sibiryak, V. Shishkov and others: according to the river. Bodaibo (1863), Nakatami (1868), Engazhimo (1870) and Takhtyge (1878). In the 1860s. Geological research in the area was carried out by P.A. Kropotkin, famous Russian geologist. In 1896, the largest joint stock company in Russia, Lenzoloto, was created, which made it possible to pool resources and attract domestic and foreign investors. In 1910, the share of foreign investment reached 65%. By this time, Lenzoloto had absorbed almost all of the Bodaibo mines (about 400 mines, 7 thousand people). Only the exceptional wealth of placers made it possible for the gold mining region to successfully develop in this remote and remote corner of Eastern Siberia.

The development of Lenovitim placers in the second half of the 19th century brought Russia to first place in the world, and only the “gold rushes” in connection with the discovery of large placers in California, Alaska and Australia pushed it to third place. In the pre-revolutionary period (before 1917), about 700 tons of gold were mined in the Bodaibo region. This area remained the largest gold producer during Soviet times, until the discovery in the 1930s. largest placers of the Golden Kolyma.

The company invested heavily in infrastructure development and geological exploration. Thus, at the end of the last century (three years before the arrival of the first train to Irkutsk via the Trans-Siberian Railway), a local railway (83 km) was built connecting the city of Bodaibo with nearby mines, which operated until 1963. In 1896 on the river. Nygri was the first hydroelectric power station in Eastern Siberia and the second in Russia (after the Zyryanovskaya HPP in Altai) to generate current. The first high-voltage power line in Russia was laid from it to the mines. An electrified railway was opened here (the first in Russia), which served for the transportation of peat and pebbles. In total, by 1914, six hydroelectric power stations were built in the region, operating in a single power system. Their electricity was used not only for production purposes, but also for domestic needs. During the same period, diamond equipment was first used for tunneling and drilling. However, in 1912, when the company, having received maximum profit (about 9 million rubles in gold), refused to allocate 100 thousand rubles. To improve the social and living conditions of the miners, the famous “Russian riot” broke out, which was brutally suppressed by government troops, who shot at a workers’ meeting and demonstration, which led to the tragic death of several people.

The best domestic and foreign geologists were invited to carry out geological exploration work, among whom was V.A. Obruchev, future academician of the USSR Academy of Sciences. In the mid-1890s. Under his leadership, several geological exploration parties worked in Bodaibo. At many mines, steam thawing of sands began, and since 1914, winter washing was introduced, which made the gold mining process year-round. By 1917, the first excavators and large electric dredges with scoops with a volume of 100 and 210 liters began to work at the mines. In 1910–1916 About 16 tons of gold were mined annually (Table 1). This record could not be broken even in Soviet times. However, the revolution interrupted the development of the company for 12 years. The next of the electric dredges planned even before the revolution, the largest in the USSR, appeared at the Blagoveshchensky mine in 1929.

Table 1.

Dynamics of gold mining in the Irkutsk region, tons

In August 1925, the USSR Government entered into a concession agreement with the British. By 1928, the company had increased gold production, which reached 70% of the pre-revolutionary level. After this, in 1930 the concession agreement was interrupted, and in 1932 the state all-Union gold mining trust "Lenzoloto" was organized, where forced labor began to be actively used. At the same time, geological exploration work aimed at increasing reserves was resumed.

In the post-war period and until now, the volume of placer gold mining in Bodaibo has been supported by the development of new gold-bearing areas, the introduction of new high-performance equipment and an increase in the share of dredging of placers. Over the years, dozens of electric dredges were designed and manufactured at the Irkutsk Heavy Engineering Plant, including small ones (for example, the Gnome dredge, which worked at the Perevoz mine along the Zhui River in the 1940s), and in the later period - powerful 600 -liter dredges with annual production of up to 1 ton of gold.

In the 1970s Using electric dredging, more than half of the total volume of gold mined in the region was obtained, the rest was accounted for by underground and hydraulic mining methods. Since 1988, the volume of gold mining began to decline. By the mid-1990s. Only a few dredges were in operation. Soon, an outflow of population began from the area. Geological exploration work was stopped. The production and social infrastructure began to collapse. In 1992, the largest Maracan dredge sank, which has not been restored to this day.

The growing problems of SMEs in alluvial gold require the transition of industry to the extraction of gold from primary deposits, the raw material base of which in the Bodaibo region is more than representative. A significant breakthrough in the development of ore gold mining occurred in the region from 1999 to 2001. The reserves at the Verninskoye and Pervenets fields were reestimated, and the reserves at the Zapadnoye, Chertovo Koryto, Golets Vysochaishy, ​​and Yubileinoye fields were calculated. The first gold was obtained at the Pervenets and Golets Vysochaishy deposits.

At the end of the section, it is necessary to write about the discovery and exploration of the largest gold deposit in Russia - Sukhoi Log (Fig. 2), the history of which begins in 1846, when in the valley of the p. Khomolkho, 30 km northeast of Sukhoi Log, the first gold placers were discovered (Wood, Popov, 2006). In the 1860s, rich alluvial gold deposits were found in many nearby areas, including small valleys on the northern and southern sides of the Sukhoi Log hill, called Radostny, Zorinsky, Sukhoi Log. More than 30 tons of gold were mined from these three alluvial deposits between 1863 and 1900. On the crest of the watershed, where numerous outcrops of large gold-bearing quartz veins were known, the Sergievsky mine operated in 1886, and the Utesisty mine in 1894, from the ores of which about 1 ton of gold was extracted, but its contents were low, and the technology of extraction and enrichment more complex than on neighboring placers, and work was stopped.

Rice. 2.

View of the Sukhoi Log field

In the 1960s, geologist V.A. Buryak, based on the geochemical anomaly and gold content in rock samples from Sukhoi Log, suggested the existence of large deposits of gold-bearing sulfide-disseminated ores. The first wells, drilled in the spring and summer of 1961, made it possible to detect gold-bearing sulfide mineralization at depth, which confirmed the forecast of V.A. Buryak. Intensive exploration of the deposit began in the fall of 1971 and was completed at the end of 1977. As a result, 209.6 km of diamond core were obtained from 846 wells; 11.7 km of underground workings were completed (adits No. 1 and 2), 1.546 km of which were driven through ore, 110.3 km of ditches. 13 thousand furrow samples, 3 large-volume technological samples of 150, 800 and 980 tons each were taken, tens of thousands of assay analyzes for gold were carried out. The data is stored in the form of multi-volume reports, master's and doctoral dissertations and forms the basis of a very detailed database on this deposit.

A feasibility study (TES) and a project of permanent conditions for the Sukhoi Log gold deposit were developed in 1975–1977. VNIIPRO Gold together with IRGI-REDMET. The reserves of the deposit were approved by the USSR State Reserves Committee in 1977 (ore - 383.5 million tons, gold - 1038.4 tons, average gold content - 2.71 g/t). Geological exploration work at the field continued until 1992.

In 2006–2007 TsNIGRI, on the instructions of Rosnedra, carried out a comprehensive technological and geological-economic revaluation of the Sukhoi Log>1 gold deposit. The technical and economic indicators of the feasibility study of conditions developed in 1977, in comparison with the indicators obtained during the revaluation of the field in 2007, have undergone significant changes. Thus, the volume of ore and metal used to justify the feasibility study in 2007 increased by 2.6 and 1.9 times, respectively (Table 2). The annual production capacity of the enterprise for ore mining increased from 12 to 34 million tons (2.8 times), for metal production - by 2.3 times. The payback period for funds invested in the construction of the enterprise decreased from 26 to 8.7 years. The level of profitability to production assets increased from 2.3 to 22.3%>1.

Table 2.

Reserves of the Sukhoi Log deposit, calculated by FSUE TsNIGRI as a result of a comprehensive technological and geological-economic revaluation>1
The first attempts to license this giant deposit were unsuccessful.
In the early 1990s, it received a license for this field (the main shareholder is the Australian company Star Technology Systems). However, in the end the company missed the development deadlines, and in 1998 the license was revoked. The Ministry of Natural Resources of the Russian Federation periodically announced a new auction. However, until the beginning of 2021, Sukhoi Log was mothballed as a strategic facility. Finally, on January 26, 2017, Russia’s largest gold deposit, Sukhoi Log, was auctioned off. The license for its development was received by a joint venture of the gold mining company (51%) and the state corporation Rostec (49%)>2. The recalculation of reserves carried out by TsNIGRI, in contrast to the State Reserves Committee of the Ministry of Natural Resources, does not satisfy PJSC Polyus in some way, because On the company’s website, the deposit only lists identified resources in the amount of 58 million ounces. At the initial stage of project development, Polyus plans to re-carry out large-scale exploration to obtain commercial reserves at the field.

Prospects for investment in gold deposits in Siberia

Taking into account the launch of a mining and processing plant in the Bodabino district of the Irkutsk region, the region may take first place in the production of valuable metal in 20 years. According to preliminary forecasts, it is planned to obtain 50 tons of gold annually.

In the future, investments are needed in the development of ore deposits, which contain not only precious metals, but also other valuable minerals.

Altai and Kuzbass attract the greatest interest from companies. Every year, regional governments put the sites of possible deposits up for auction.

Legalization of gold mining

For a long time, only legal entities that received a license for this type of activity could engage in gold mining. In 2017, D. Medvedev signed changes to the law “On Subsoil” as part of the liberalization of the situation in the industry.

According to the new legislation, mining can be carried out by an individual. To do this, it is necessary to rent a plot of land on which work is supposed to be carried out. However, there are restrictions:

1. Explosives cannot be used.
2. You can dive into the ground no more than five meters.
3. Use only superficial methods.

Prospects

With the commissioning of the Sukholozhsky Mining and Processing Plant, the gold industry will once again become one of the leading industries of specialization throughout Eastern Siberia, and the Irkutsk region will take a leading position among the main gold-mining regions of the country.

In addition to the development of the unique Sukholozhskoye deposit, it is advisable to quickly develop other relatively small gold ore deposits, such as Yubileinoye, with richer (10 g/t) ores. The development of ore deposits will ensure year-round production and eliminate the notorious problem of seasonal lending to the industry.

The development of ore gold deposits should not interfere with the exploitation of gold placers. The use of technologies for the extraction of fine (so-called “thin”) gold, which until now went into the “tails,” is quite promising. This will open up the possibility of secondary exploitation of abandoned dumps of underground and dredge mining, where the most productive areas can produce up to 60% of the previous volume of gold mining.

The revival of the gold mining industry can be facilitated by the development of the precious metals market in Russia, which will increase the economic potential of the region and stabilize the difficult socio-economic situation in the gold-mining Bodaibinsky administrative region. The formation of such a market will be a unique alternative to mandatory federal budget expenditures associated with targeted financing of the gold mining industry. At the same time, stable sales of mined gold and financing of the industry will no longer depend to such an extent on the volume of purchases of the precious metal for government needs. It is also important that increasing the liquidity of Russian gold on the domestic market and its more active use as a financial instrument and a store of value will help push foreign currencies out of the financial market and stimulate long-term investments by the population in the development of the domestic gold industry.