In recent years, non-zinc sulfide minerals (zinc oxide minerals and silicate minerals) have attracted the attention of mining industry, exploration industry and economic geology. This kind of deposit is even called "new deposit in the future". In fact, this kind of deposit has long been known and mined. The development of Skorpion supergene zinc oxide deposit in southern Namibia has triggered a new wave of attention and research on this kind of deposit. The deposit is located 85 kilometers northeast of Orangemond. The whole deposit was originally a volcanic massive sulfide deposit, which was discovered by Anglo-American Company in 1976. The deposit contains 24.6 million tons of supergene oxide ore, and zinc 10.6% (open pit reserves 210.4 million tons, zinc 10.6%), mainly zinc silicate and zinc carbonate. In addition, there are 60 million tons of mixed oxide-sulfide ore resources, containing 6% ~ 8% zinc and 0/%lead/kloc-. Zinc is about 6.8 million tons and lead is about 600,000 tons. In the past, it has not been developed because of smelting difficulties. Later, ZincOx technology was mainly developed by N.Masson, a Belgian chemical engineer working in Union Miniere at that time (with the participation of A.Woollett of Reunion Mining Company). This is a Shui Ye process, and also a solvent extraction electrodeposition technology with low cost, which can produce high-grade metallic zinc. Because of this technology, the deposit was officially exposed in September 2003 after further exploration, with an annual production capacity of 6.5438+0.5 million tons of zinc metal and a service life of at least 654.38+0.5 years. This mine has become the largest zinc mine in the world 10, and its cost is almost the lowest. 1997, Masson and Woollett set up ZincOx company to find other zinc oxide deposits for development. However, most of these deposits are not large enough. Recently, the Jabali Jabali zinc oxide mine project located at 1 10 km northeast of Sana 'a, Yemen, has been confirmed by feasibility study, with a resource of12.6 million tons, containing 8.9% zinc, 0/.2% lead and 68g/ ton silver. The ore body has not yet reached the edge. Shui Ye method patented by ZincOx Company can be used, and the recovery rate of zinc is 77%. It may be built in 2006 and put into trial production in the second half of 2007, with a service life of 1 1 year. ZincOx is also exploring the Shaimerden zinc oxide mine in Kazakhstan, which is expected to be put into production in early 2006. In 2003, the resource of Baden-Padan zinc mine in Dafumeisu, Thailand was 4.6 million tons, and the zinc content was 65,438+02.3%. With active exploration, zinc silicate and zinc sulfide can be used in the same production process.
In 2002, it was reported that supergene non-sulfide zinc deposits currently account for about 65,438+00% of the world's known zinc reserves, but in 2004, it was reported that non-sulfide zinc deposits accounted for less than 4.5% of the world's total zinc resources. It is worth re-studying now because: ① it is attractive to mining industry, it contains less lead, sulfur and other harmful elements, and can be harvested by SX- electrowinning technology, which consumes less energy and has higher comprehensive economic value. ② A new comprehensive classification of this kind of deposits is put forward, and it is considered that non-zinc sulfide deposits are mainly supergene deposits, but there are also primary deposits and deep deposits. Supergene deposits are divided into:? Directly explain the causes, such as some deposits in Iran, Peru, Ireland and Kazakhstan; ⑥ The surrounding rocks are metasomatic, such as Corpi Weng in Namibia and some deposits in Myanmar and Thailand; ? Residual and karst filling, such as some deposits in Thailand and Vietnam. Deep (primary) deposits can be divided into tectonic-controlled (hydrothermal) deposits (such as the Bertana zinc-silicon deposit in the Flinders Mountains, some deposits in Brazil, Zambia and Namibia) and layered deposits (such as Franklin layered zinc oxide-silicate deposit in New Jersey, USA). ③ The existing researches on supergene zinc deposits need to be updated. ④ This kind of zinc ore can be studied by stable isotope method and can be directly dated. ⑤ Primary non-zinc sulfide deposits (such as many zinc-bearing deposits) are a new type, which deserves further study, including the metallogenic and sedimentary relationship between some layered primary non-zinc sulfide deposits and layered iron oxides or sulfides. ⑥ The exploration methods of such deposits are different from sulfide deposits (such as geophysical and geochemical exploration and mineralogical research). Many of these deposits have yet to be discovered on the surface and can be identified by simple mineral methods. Finally, we need to point out that the exploration, mining and research of this kind of deposit are noteworthy and may be important in some areas. But in general, it is only a small part of zinc mine.
There are many lead-zinc mines in Iran, some of which are large in scale, as well as oxidized ores and mixed ores of oxidized ores and sulfide ores. For example, the Angouran deposit in Zambia province in northwestern Iran is one of the largest and most abundant non-zinc sulfide deposits in the world. The resources of 65,438+0,999 are: 65,438+0,350,000 tons of non-sulfide minerals, containing 26.4% zinc and 4.5% lead (mainly carbonate minerals, mainly smithsonite, mostly massive and breccia); 3.2 million tons of sulfide ore, containing 37.0% zinc and 2.32% lead; The mixed ore is 2 million tons, containing 3 1.2% zinc and 4. 1% lead. This ore also contains a lot of silver. That is, it contains 5.372 million tons of zinc and 764,000 tons of lead. The sulfide ore is related to breccia and belongs to Mississippi valley type deposit, which occurs in Precambrian-Cambrian metamorphic complex (amphibolite, schist and marble in greenschist facies-amphibolite facies). Iran's Iranian lead-zinc deposit contains150,000 tons of sulfide ore, containing 4% zinc and 2% lead. 4 million tons of mixed ore, containing 7% zinc and 0/%lead/kloc-; Oxidized ore140,000 tons, containing 654.38+02% zinc and lead (mainly zinc). At present, the largest world-class Mehdiabad Pb-Zn-Ag deposit in Iran is located in the middle of Iran, 85 kilometers away from Yazd. This is a Mississippi valley deposit hosted by carbonate rocks, with an estimated resource of 75.2 million tons, containing 7.38% zinc, 2.38% lead and 62 g/ton silver. Another estimated resource is 654.38+42.7 million tons, containing 7. 1% zinc, 2.32% lead and 46g/ ton silver. Zinc is about/kloc-0.5 million tons, lead is about 5 million tons, silver is about/kloc-0.000 tons, and barite is about/kloc-0.000 tons. In 2004 and 2005, I was conducting an encryption exercise. Feasibility study has been carried out, with an annual output of 500,000 tons of metallic zinc and 654.38+800,000 tons of lead-silver concentrate. First open-pit mining, acid leaching to produce metal zinc, and then well mining, the mine life is more than 30 years. 33% of the known resources are oxide minerals. The deposit covers an area of 2.5× 1.5 square kilometers, and the north and south have not yet reached the edge. The designed mine is 2.5km× 1.8km with a depth of 400m. The feasibility study was completed in early 2006. At present, the total resources (taking 2% of zinc as the cut-off grade) have increased to 394 million tons, containing 4.2% of zinc, 0/.6% of lead and 36g/ ton of silver, that is, 0/65,500 tons of zinc, 6.3 million tons of lead and 0/4 of silver/kloc-.
The lead-zinc-silver deposit abroad in the last two years can be regarded as a new discovery, that is, the Navidad super-large silver-lead deposit was discovered in Central chubut province, Patagonia, southern Argentina. This is the "geological hammer plus hiking shoes" discovered by a small company in the grass-roots exploration in February 2002. By the second half of 2005, the amount of silver resources is 65,438+00,560 tons, and the amount of lead resources is about 654,380+04,000 tons (see the special introduction later). Diablillos silver-gold deposit in Salta province in northern Argentina occurs in volcanic rocks. It is estimated that the open-pit mining resources are 42 million tons, including 70g/ ton of silver and 0/.0g/ton of gold, that is, 2940 tons of silver. It is estimated that the gold resources are 25 million tons, and the gold content is 1.0g/ ton.
Peru is also a country rich in silver. The Toromochate porphyry Cu-Mo-Ag deposit, which is currently being explored, reported in June 2005 that the confirmed and estimated silver resources have exceeded 65,438+02,000 tons (see "Copper" in the previous section for details). The Morococha silver deposit (located at about 150km northeast of Lima) not far from the deposit has 1420 tons of silver resources, of which the proven and approximate ore reserves are1060,000 tons, including 269g/ton of silver, 4.94% of zinc and 0.90% of lead. The replacement deposit project of silver, copper and manganese in Berenguela mine, 50 kilometers west of Juliaca in southern Peru, was continuously mined in the early 20th century, with a silver output of more than 340 tons 1905 ~ 1965. The recoverable reserves are140,000 tons, including silver 125g/ ton (including 1750). Near the Las Bambas skarn deposit (mainly copper) in southern Peru, the Limamayo Zn-Pb-Ag-Cu skarn mineralization system was discovered three years ago. Recently, Xiong Xi Company discovered a new silver mine with great ore potential in Colani exploration area, 200 kilometers north of Puno in southern Peru. According to the results of the trench and the first four boreholes, the mineralization thickness reaches 65,438+000 meters. This area is a lead-silver mining area in history, which was mined in the 1960s. The deposit is covered with tertiary igneous clastic rocks and breccia, as well as underlying Paleozoic sedimentary rocks. In the 1990s, a small number of boreholes were drilled, with different degrees of mineralization, including 0.24% copper, 3g/ ton gold and 438g/ ton silver. In 2003, Riotinto Company purchased this 23-square-kilometer mine as the target area of porphyry copper mine, and its field work determined a 2×5-square-kilometer altered area with low-sulfur gold and silver mineralization. Three anomalies were identified in the soil geochemical survey: ① 1. 1 km2 silver anomaly (average 49g/ ton of silver); ②0.6 km2 gold anomaly (average gold 0.49g/ ton, silver 1 1g/ ton); ③ 0.5km2 Cu-Au anomaly (average Cu 707× 10-6, Au 0.36g/ ton). Take a sample from the surface. Riotinto Company decided that it could not meet the requirements of its porphyry copper exploration system, and sold 70% of the rights and interests of the project to Xiong Xi Company in 2005. The latter took a block sample in the northern silver anomaly area, containing high silver and low gold, and silica and barite were found. After trench exploration and drilling, it is considered to be a long-distance low-sulfur epithermal silver deposit around the weak porphyry copper system, and what is seen in drilling is silver-lead (zinc) mineralization. Mineralization occurs at the bottom of tertiary volcanic rocks (tuff, containing a small amount of andesite), which are veined, brecciated and reticulated, with silicified and strong brown iron hematitization and manganese oxide. At present, the total resources of the three deposits are 1. 1.55 million tons, including 8,560 tons of silver, 0/.1.65438 million tons of lead and 570,000 tons of zinc.
The base metal (lead-zinc-silver) mineralization zone in Aripuana, Mato Grosso, Brazil is a volcanic massive sulfide mine, and the length from Arex to Mocoto exploration area is more than 12 km along the strike. The exploration resources have increased in the past two years, among which the estimated and predicted resources of Arex and Ambrex deposits are 23.74 million tons, containing 5.07% zinc, 52.96 g/ton silver, 0.43% copper and 0.4 g/ton gold. The Wazante zinc deposit in Minas Gerais, Brazil, is a Proterozoic (600-740 million years) exhalation deposit, which occurred in 1969. By the end of 1997, about/kloc-0.3 million tons of ore had been mined, with an average of 20% zinc, and 2,066,800 tons of zinc had been recovered. At present, the annual output of zinc is 654.38 million tons, zinc oxide is 5,000 tons and cadmium is 75 tons. To the depth of 250 meters, there are still 8.9 million tons of reserves and 22% zinc.
Mexico is a country rich in silver, lead and zinc. In recent years, the Penasquito silver-gold (lead-zinc) project in Zacatecas, the central part of the country, has delineated three deposits, among which the estimated sulfide resources of Penasco deposit are10.24 billion tons, containing 27.5g/ton of silver, 0.5g/ton of gold, 0.3 1% of lead and 0.64% of zinc. The estimated resources are 84 million tons, including 26 g/ton of silver, 0.5 g/ton of gold, 0.29% of lead and 0.66% of zinc. The resource of overlying oxide ore is estimated to be 26 million tons, including silver 19.7 g/ton, gold 0.2 g/ton, lead 0.24% and zinc 0.26%. The estimated resources are 8 million tons, including silver 15.8g/ ton, gold 0.2g/ ton, lead 0.2% and zinc 0.26%. * * * 6232 tons of silver, gold 1 10 tons, lead 700,000 tons and zinc 1.43 million tons. The other is the ChileColorado deposit, whose mineralization is related to the porphyry intrusive alteration zone under the explosive breccia. There are sulfide ores with proven and estimated resources of 1.49 billion tons, containing 34.3 g/ton of silver, 0.3 g/ton of gold, 0.28% of lead and 0.84% of zinc. The estimated resources are 45 million tons, including silver 2 1. 1g/ ton, gold 0.2g/ ton, lead 0.2% and zinc 0.48%. The proven and estimated oxide ore resources are 25 million tons, including silver 15.3g/ ton, gold 0. 15g/ ton, lead 0.26% and zinc 0.30%. The estimated resources are 5 million tons, including silver 1 1.6 g/ton, lead 0. 18%, zinc 0. 17% and gold 0. 1 g/ton, that is, the deposit contains 6500 tons of silver. There is also Azul breccia deposit, with an estimated sulfide resource of 765,438+200,000 tons, containing 3 1.5g/ ton of silver, 0. 1.5g/ ton of gold, 0.36% of lead and 0.72% of zinc. Oxidized ore19.2 million tons, including silver 13 g/ton and gold 0. 1 g/ton, that is, silver 2490 tons, gold 12 tons, lead 256,000 tons and zinc 5120,000 tons. The three deposits have a total of silver10.52 million tons, gold10.80 tons, lead10.53 million tons and zinc of 3.5 million tons, which is a world-class silver-gold lead-zinc mine area. According to the recent drilling, there are currently 27,430 tons of silver, 445 tons of gold, 2.4 million tons of lead and 7,654.38+million tons of zinc in this mining area. The mining area was discovered in the second half of19th century. After geophysical and geochemical exploration and drilling, drilling started from 1994 ~ 1997. 200 1 of Francisco I Madero mine in this state was put into production, with a reserve of 30 million tons, containing 5.2% zinc and 0/.10% lead. It also contains a lot of silver. This discovery was made through careful surveying and mapping, understanding the mineralization geological model of the mining area and drilling. There are also several tailings mining projects in the state. La Pitarrilla silver mine, located at the northwest 170 km of durango, Durango, has proven resources of 27.2 million tons, including silver120.6g/ton. The estimated resources are 35.6 million tons, including silver 1 12.5g/ ton; The estimated resources are 64.4 million tons, including 92.7 grams of silver/ton, totaling silver 13250 tons. The feasibility study results of Alamo dorado silver-gold mine in Sonora state in 2002 show that the open-pit heap leaching reserves are 35.5 million tons, including 67 g/ton of silver and 0.26 g/ton of gold. It is estimated that the annual output will be 4.5 million tons of ore, 0/87 ton of silver/kloc and 0.9 ton of gold, with a service life of 8 years. Then continue to work.
The super-large Sancristobal silver (lead-zinc) deposit discovered in the southwest of Bolivia in the mid-1990s is expected to be put into production in the second half of 2007, with a daily output of 40,000 tons of ore, an annual output of 840 tons of silver and 260,000 tons of zinc (zinc content in concentrate). Service life 16 years, can handle 229 million tons of ore, with an average of 63.28 g/ton of silver, 1.6% of zinc and 0.59% of lead. The San Bacelo Ma alluvial silver mine project in the south-central part of the country (near the Cerro Rico historical mining area in Potosi) contains silver from gravel deposits. After the pre-feasibility study in 2000, continue to work. In 2003, the calculated reserves were 32 million tons, and the silver grade was 1 19g/ ton, that is, it contained 3,800 tons of silver. The annual output of silver is about 187 ~ 250 tons, and tin is also a by-product. Life span is 15 years.
Some known important mineral resources are still expanding. 1997 After the discovery of Ana Lahacque deposit in Honggou Pb-Zn-Ag mining area, Alaska, USA, the richest zinc mineralization (zinc up to 2 1% ~ 30%) was drilled about 5 kilometers northwest of the deposit. A new ore-rich body with a thickness of more than10m, containing zinc 19.2% ~ 32.3%, lead 3.0% ~ 12.8% and silver12 ~ 93g/ton was discovered beside the lead-zinc mine bed in Galmoy, Ireland. The production capacity of the Precambrian world-class rampulla Agucha lead-zinc (silver) deposit in Rajasthan will increase from the current 2.3 million tons of ore per year to 3.75 million tons. Due to recent drilling, its current reserves have increased to 50,654.38+million tons, including 65,438+02.8% zinc and 65,438+0.9% lead. It is 25% higher than the previous year, and the service life can be extended by 3 years after expanding production capacity. The deposit also has 24.9 million tons of ore resources, including zinc content of 12.4% and lead content of 1.7%. The existing total resources (including reserves, 9.5 million tons of zinc and 6.5438+0.37 million tons of lead) exceed the total resources of 9.2 million tons of lead and zinc when put into production. At present, the proven and approximate reserves of Zinkgruvan mine in southern Sweden are 9.5 million tons, containing 9.8% zinc, 4.8% lead and 97 g/ton silver. In addition, the total resources at all levels are 6.5438+0.04 million tons, including 9.7% zinc, 3.9% lead and 94 g/ton silver. There are 3.5 million tons of copper resources, including 3. 1% copper, 0.4% zinc and 49 g/ton silver. The deposit belongs to Precambrian volcanic massive sulfide deposit. The existing resources of prairie creek mine in northwest Canada are about110.9 million tons, of which the zinc content is 12.5%, the lead content is 10. 1%, and the copper content is 0.4%, which belongs to the Mississippi valley type dominated by carbonate rocks. The Howard Mountain Pass super-large jet sedimentary lead-zinc deposit has been explored in recent two years. Ruddoek Creek sedimentary jet type (or Brokenshire type) Pb-Zn-Ag deposit, north of Rafflestock 100 km, British Columbia, Canada, has been explored as early as 1960 ~ 1975 and is being drilled recently. Kipsi, a famous polymetallic ore with a long history in Congo (Gold), is being further studied. There are still169,000 tons of confirmed and estimated resources, including zinc 16.7% and copper 2.2%. Some major lead-zinc deposits in Tunisia were initially thought to be related to a series of salt diapirs. Recently, scholars from Kingston University in the United Kingdom put forward a new metallogenic model, arguing that the deposit belongs to the Mississippi valley type and is distributed along the thrust surface of the thrust edge of a Cretaceous extensional basin.
The Handiza volcano polymetallic massive sulfide deposit in southeastern Uzbekistan has been widely explored for many years during the Soviet era, and the underground tunnel is19000m. Further drilling started from 1996. The feasibility study conducted by Malaquin De Mining Company has achieved positive results. The total resources at all levels are 1, 446,5438+0,000 tons, including 7.24% zinc, 3.50% lead, 0.86% copper, 0.38g/ ton gold and 0.34g/ton silver. Its reserves are 8.88 million tons, including zinc 8.04%, lead 3.82%, copper 0.97%, gold 0.37 g/ton and silver 1.26 g/ton. The Tumurting Aobao large zinc (lead) deposit in Mongolia is located near Joy Balsam, about 550 kilometers east of Ulaanbaatar, with an ore resource of 7,654,380+million tons. ), containing zinc 13.7%, can be mined in the open pit for 25 years, and then mined in the well 10 years. This is a Sino-Mongolian joint venture project, which was put into production in 2005. The famous Brokenshire Pb-Zn-Ag deposit in New South Wales has been mined for more than 100 years. At the beginning of 200/kloc-0, it was reported that 200 million tons of ore had been mined, valued at 70 billion Australian dollars (200 1 price at the beginning of the year). There are still considerable reserves and resources. According to the recent drilling results in the mineralization target area in western China, the ore resources are16.7 million tons, containing 3.2% zinc and 2.2% lead (with 2% lead+zinc as the cut-off grade). The "Black Star" open-pit mining project in Elsa Mountain Mining Area, Queensland, Australia is scheduled to be put into operation in 2005, with a resource of 24.5 million tons, containing 5. 1% zinc, 2.7% lead and 54 g/ton silver. In the first phase, 8.4 million tons of development reserves have been delineated, including 5.2% zinc, 3.5% lead and 60g/ ton silver, and the stripping-mining ratio is 4∶ 1. The planned pit is 200 meters deep and will be mined for at least 5 years. Bronx Co-Pb (Cu-Ni) polymetallic project in northern Australia is located 90 kilometers south of Darwin Harbour, which is a traditional uranium exploration area. CRA Company searched for uranium in 1960s, but also knew the lead prospect of this deposit, and drilled in the mid-1960s. In the early 1990s, another company conducted exploration, and by the beginning of 200 1, the pre-feasibility study had been completed, with a resource of 82 million tons, including 2.28% of lead, 0.77% of cobalt, 0.77% of copper and 0.011%of nickel. It is a stratabound sulfide deposit, which is similar to the copper belt in Central Africa in geology. Magellan lead mine project near Viruna in central Western Australia is a carbonate lead mine with secondary lead enrichment zone, which consists of Magellan deposit and satellite deposit CANO (3.8 million tons of ore). * * * More than 600 boreholes have been completed, and the proven and estimated resources are 1.565438+ million tons, with a lead content of 6.4%, of which the reserves are 1.2 million tons and the lead content is 6.8%. In addition, the estimated resource is130,000 tons, and the lead content is 4.3%. There are still some exploration areas to be drilled nearby. It was put into production in 2005 and reached its output in 2006, with an annual output of 654.38 million tons of lead. There are some Mississippi Valley lead-zinc deposits on Leonard continental shelf in Western Australia. In fiscal year 2003, it produced1760,000 tons of zinc and 70,000 tons of lead. The total reserves are 6.5438+0.042 million tons, including 6.2% zinc and 654.38+0.7% lead. The total resources are 2,265,438+800,000 tons, containing 6.9% zinc and 2.8% lead. The Doudard Pb-Zn deposit in Doudard District, Baluchistan Province is a Jurassic sedimentary exhalation deposit. The estimated resources in 200 1 year are 143 1 10,000 tons, including 8.6% of zinc and 3.2% of lead, that is, 0.23 million tons of zinc and 458,000 tons of lead. Dairi Pb-Zn-Ag deposit, located at 120km south of Medan in northern Sumatra, Indonesia, is mainly an advanced sedimentary exhalation deposit, which occurs in carbonaceous shale and siltstone with a thickness of 30 ~140m. The deposit was discovered in the late period of 1997. After geological mapping, geophysical and geochemical exploration and drilling, at the beginning of 200 1, the estimated resources of the Hitam deposit in Anjing, south section of the mining area were 7.5 million tons, containing zinc 16.7% and lead 10.3%. The estimated resources are 2.5 million tons, including zinc 1 1.3%, lead 6.8% and silver 1.3 g/ton (all with the cut-off grade of 5% zinc equivalent), totaling zinc 1.6 million tons, lead 940,000 tons and silver. Stratified coal seams occur in shale with a thickness of 50 ~ 70 meters, with an average thickness of 12 meters. The ore is massive to flaky and consists of pyrite, galena and sphalerite. There are some metasomatic lead-zinc deposits in limestone-dolomite series under shale. No edge has been explored along the north-south strike of the ore body. Drilling continues. The drilling results in Lae Jehe exploration area 1.3km and Bongkaras exploration area 2.2km are also encouraging. For example, the mineralization of the Laire River extends from the surface to a depth of more than 400 meters, with a thickness of 4 ~ 10 meter. The zinc content is mostly around 10%, and the lead content is over 6%. Trying to double the mineral resources by drilling.
After further work, the resources of Bowdens silver (lead-zinc) deposit in New South Wales, Australia have increased. Taking 40g/ton of silver as the cut-off grade, the proven and estimated resources are 3,665,438+ten thousand tons, including 51.8g/ton of silver, 0.24% of lead and 0.32% of zinc. The estimated resources are 22.9 million tons, including 42.5g/ton of silver, 0.20% of lead and 0.30% of zinc. The famous Irmiter super-large silver deposit in Moroccan Little Atlas Mountains is Neoproterozoic epithermal deposits, which has produced a large amount of silver, and there are still 8,000 tons of silver resources proved. The Late Permian sandstone-shale copper-silver deposit in Poland not only has huge copper resources (more than 33.5 million tons of copper), but also contains very huge silver resources (9 1400 tons of silver). The general situation has been mentioned in the previous section "Copper". Silver is the production or by-product of copper, which exists in the form of natural silver or mainly as an associated element in bornite and chalcocite. It is mainly mined in three mines in Lubin-Glogau mining area in southwest Poland, with an annual output of about 28 million tons of ore and an average copper content of 1.9%. In 2000, the output of refined copper was 51.8000 tons and silver 1.44 tons. It is mined by KGHM Poland, the largest copper producer in Europe and the ninth largest silver producer in the world. The average grade of silver in the main deposits is 79 g/t and 54 g/t respectively. The silver reserves of the three major deposits are 28,000 tons, 29,000 tons and 6.5438+0.8 million tons respectively.
The Auzel Pb-Zn deposit (northwest of Chita), 250km northeast of Ulan-Ude, Buryatia, Russia, is a layered lenticular sulfide ore body in the volcanic sedimentary rock series of the Early Cambrian. At present, the estimated total resources are 65.438+0.57 billion tons, including 5.2% zinc and 654.38+0% lead (with 2% zinc as the grade limit), that is, 865.438+0.6 zinc.