Mining of iron ore. Minerals: Iron ores How iron ore is mined in the world

Stoilensky GOK in the Belgorod region is one of the leading producers of iron ore raw materials: it accounts for more than 15% of commercial ore production in Russia. Filming took place over five years and took over 25 days in total. Great photo story.

1. Iron ores are natural mineral formations containing iron and its compounds in such a volume that the industrial extraction of iron from these formations is advisable. SGOK takes raw materials from the Stoilenskoye deposit of the Kursk magnetic anomaly. From the outside, such objects look like most industries - some kind of workshops, elevators and pipes.

3. Mining is carried out in an open way. To get to rich ore miners remove and dump tens of millions of cubic meters of earth, clay, chalk, and sand into dumps.

4. Loose rocks are mined with backhoes and draglines. "Backhoes" look like the usual buckets, only in the SGOK quarry they are large - 8 cubic meters. m.

5. In such a bucket, 5-6 people or 7-8 Chinese people can freely accommodate.

6. Loose rocks, which miners call overburden, are transported to dumps by trains. Every week the horizons on which the work is done change their shape. Because of this, it is constantly necessary to shift the railway tracks, the network, transfer railway crossings etc.

7. Dragline. The bucket on a 40-meter boom is thrown forward, then the ropes pull it towards the excavator.

8. Under its own weight, the bucket rakes in about ten cubic meters of soil in one throw.

9. Machine room.

10. The driver needs a lot of skill to unload such a bucket into the car without damaging the sides and without hitting the high-voltage line of the locomotive contact network.

11. Excavator boom.

12. A train with dump cars (these are self-tipping cars) takes out overburden to dumps.

14. Reverse work takes place on the dumps - the roof of the wagons is stored by an excavator in neat hills. At the same time, loose rocks are not just piled up, but stored separately. In the language of miners, such warehouses are called man-made deposits. Chalk is taken from them for the production of cement, clay - for the production of expanded clay, sand - for construction, black soil - for land reclamation.

15. Mountains of Cretaceous deposits. All this is nothing but deposits of prehistoric marine life- mollusks, belemnites, trilobites and ammonites. About 80 - 100 million years ago, a shallow ancient sea splashed in this place.

16. One of the main attractions of Stoilensky GOK is the mining and stripping complex (GVK) with the key unit - the KU-800 walking bucket wheel excavator. The GVK was manufactured in Czechoslovakia, assembled in a SGOK quarry for two years, and put into operation in 1973.

17. Since then, a bucket wheel excavator has been walking along the sides of the quarry and cutting off chalk deposits with an 11-meter wheel.

18. The height of the excavator is 54 meters, weight - 3 thousand 350 tons. This is comparable to the weight of 100 subway cars. From this amount of metal, 70 T-90 tanks could be made. Clickable:

19. The excavator rests on a turntable and moves with the help of "skis", which are driven by hydraulic cylinders. To operate this monster, a voltage of 35 thousand volts is required.

20. Mechanic Ivan Tolmachev is one of those people who participated in the launch of the KU-800. More than 40 years ago, in 1972, immediately after graduating from the Gubkinsky Mining Technical School, Ivan Dmitrievich was accepted as an assistant to the driver of a rotary excavator. That's when it had to young specialist run up the stairs! The fact is that the electrical part of the excavator turned out to be far from perfect, so more than one hundred steps had to be overcome until you find the reason for the failure of one or another node. Plus, the documents were not completely translated from Czech. In order to delve into the schemes, I had to sit over the papers at night, because by morning it was necessary to figure out how to eliminate this or that malfunction.

21. The secret of the longevity of the KU-800 is in its special mode of operation. The fact is that, in addition to scheduled repairs during the working season, in winter the entire complex is undergoing major repairs and restructuring of conveyor lines. Three months GVK prepare for the new season. During this time, they manage to put in order all the components and assemblies.

22. Alexei Martianov in the cab overlooking the excavator rotor. The rotating three-story wheel is impressive. In general, traveling through the galleries of the KU-800 is breathtaking.

You have these impressions, probably already a little dulled?
- Yes, there is, of course. I have been working here since 1971.
- So, in those years, this excavator did not exist yet?
- There was a platform on which it was just beginning to be mounted. He walked here in knots, for about three years he was assembled by the Czech installation chiefs.
- Was it an unprecedented technique at that time?
- Yes, this is the fourth car that came off the assembly line of the Czechoslovak manufacturer. The newspapermen attacked us then. Even in the journal "Science and Life" they wrote about our excavator.

23. Hanging halls with electrical equipment and switchgear serve as a counterweight to the boom.

Of course, I understand that this is a walking excavator. But I still can’t imagine how such a “colossus” can actually walk?
- She walks very well, turns well. A step of two and a half meters takes only one and a half minutes. Here, at hand, is the step control panel: skis, base, stop, excavator turn. In a week we are preparing to change the place of deployment, in reverse side let's go, to where the conveyor is being built.

24. Aleksey Martianov, foreman of GVK machinists, talks about his excavator with love, as if it were an animated object. He says that he has nothing to be ashamed of in this: each of his crew also treats his car. Moreover, the specialists of the Czech manufacturer, who oversee major repairs of the excavator, are beginning to speak of a living thing.

25. Only on the top platform of the excavator, forty meters from the ground, you feel it true dimensions. It seems that you can get lost in the stairways, but in these intricacies of metal and cable communications there are also workers and engine rooms, a hall with electrical equipment, switchgear, compartments for hydraulic units for walking, turning, devices for lifting and extending a rotary boom, cranes, conveyors.

With all the metal and energy intensity of the excavator, only 6 people work in its crew.

26. Narrow iron ladders in places with moving steps entangle the excavator like forest paths. Endless rivers of wires run through the excavator.

27. - How do you manage it? Do you have any secrets? Here comes, for example, new person, after how many months it will be possible to put him here, in this chair?
- It's not months, it's years. Learning to work in the cockpit, crash, walk is one thing, but to feel the car is quite another. After all, the distance from me to the driver of the loading boom is 170 meters, and we must hear and see each other well. I don't know what to feel with my back. There is, of course, a speakerphone here. All five drivers can hear me. And I hear them. You also need to know the electrical circuits, the device of this huge machine. Who masters quickly, and who only after ten years becomes a machinist.

28. The design of the KU-800 still surprises with engineering solutions. First of all, optimal calculations of bearing units and parts. Suffice it to say that excavators similar in performance to the Czech KU-800 have significantly big sizes and mass, they are up to one and a half times heavier.

29. The chalk cut by the rotor travels about 7 kilometers through a conveyor system and is stored in the chalk mountains with the help of a spreader.

30. For a year, such a volume of chalk is sent to the dumps, which would be enough to fill a two-lane road 1 meter high and 500 kilometers long.

31. Loading boom driver. In total, a shift of 4 people works on the spreader.

32. The spreader is a reduced copy of the KU-800 except for the absence of a rotary wheel. The excavator is the opposite.

34. Now the main useful mineral in the quarry of Stoilensky GOK, these are ferruginous quartzites. Iron in them is from 20 to 45%. Those stones where iron is more than 30% actively react to the magnet. With this trick, miners often surprise guests: “How is it that ordinary-looking stones are suddenly attracted by a magnet?”

35. There is not enough rich iron ore in the quarry of the Stoilensky GOK. She covered a not very thick layer of quartzite and she was almost worked out. Therefore, quartzite is now the main iron ore raw material.

37. To get quartzites, they are first blown up. To do this, a network of wells is drilled and explosives are poured into them.

38. The depth of the wells reaches 17 meters.

39. Stoilensky GOK conducts up to 20 explosions per year rock. At the same time, the mass of explosives used in one explosion can reach 1,000 tons. In order to prevent a seismic shock, the explosive is detonated by a wave from well to well with a delay of a fraction of a second.

40. Badaboom!

43. Large excavators load ore crushed by an explosion into dump trucks. About 30 BelAZ trucks with a carrying capacity of 136 tons each operate in the SGOK open pit.

44. 136-ton Belaz is filled with a hill for 5-6 revolutions of the excavator.

48. Clickable:

49. Caterpillar the size of a man.

51. Dmitry, the driver of Belaz, says that driving this "elephant" is no more difficult than the Six Zhiguli.

52. But the rights must be obtained separately. The main thing is to feel the dimensions and never forget how much weight you work with.

60. Belaz transport ore to the transfer warehouses in the middle part of the quarry, where other excavators are already reloading it into dump cars.

63. Loaded trains of 11 wagons are sent to the processing plant. Electric locomotives have to work hard, because transporting 1150 tons of ore along the ascending serpentine is not an easy task.

64. Loaded for ascent and empty for descent.

66. On enrichment plant ore is unloaded into the mouths of huge crushers.

67. During the enrichment process, the ore goes through several stages of crushing. On each of them, it becomes smaller and smaller.

68. The purpose of the process is to get the ore ground to almost fine sand.

69. The magnetic component is taken from this crushed mass of quartzite with the help of magnetic separators.

72. In this way, iron ore concentrate with an iron content of 65 - 66% is obtained. Everything that is not magnetized to the separators is called waste rock or tailings by the miners.

73. Tailings are mixed with water and pumped into special reservoirs - tailings.

74. Tailings are considered man-made deposits, because, perhaps, in the future they will learn how to extract valuable elements from them. To prevent dust from the tailing dumps, which causes the wrath of environmentalists and local residents, tails are constantly watered with rain with a rainbow. The benefit of water from the quarry - heaps!

75. To prevent the quarry from flooding with water, at a depth of about 200 meters underground, a girdle network of drifts of the drainage shaft was punched underground.

76. From drifts, the total length of which is about 40 kilometers, upwards, wells were drilled into the quarry, which intercept groundwater.

78. Every hour, 4,500 cubic meters of water are pumped out of the drainage mine of Stoilensky GOK. This is equal to the volume of 75 railway tanks.

80. Thank you very much for your attention and patience!

iron ore called natural mineral formations that contain iron in large quantities and such chemical compounds that its extraction is possible and expedient. The most important are: magnetite, magnomagnetite, titanomagnetite, hematite, hydrohematite, goethite, hydrogoethite, siderite, ferruginous chlorites. Iron ores differ in their mineral composition, iron content, useful and harmful impurities, formation conditions and industrial properties.

Iron ores are divided into rich (more than 50% iron), ordinary (50-25%) and poor (less than 25% iron) Depending on chemical composition they are used for iron smelting natural form or after enrichment. Iron ores used to make steel must contain certain substances in the required proportions. The quality of the resulting product depends on this. Some chemical elements(other than iron) can be extracted from the ore and used for other purposes.

Iron ore deposits are divided by origin. Usually there are 3 groups: igneous, exogenous and metamorphogenic. They can be further subdivided into several groups. Magmatogenic are formed mainly when exposed to various compounds high temperatures. Exogenous deposits arose in the valleys during the deposition of sediments and Metamorphogenic deposits are pre-existing sedimentary deposits that were transformed under conditions of high temperatures. The largest number iron ore is concentrated in Russia.

The Kursk magnetic anomaly includes the Prioskolskoye iron ore deposit and the Chernyanskoye iron ore deposit.

The content of iron in industrial ores is from 16 to 72%. Among the useful impurities are Ni, Co, Mn, W, Mo, Cr, V, etc., among the harmful ones are S, R, Zn, Pb, As, Cu. iron ores by genesis are divided into, and (see map).

Basic iron ores

Industrial types of iron ores are classified according to the predominant ore mineral. Magnetite ores are composed of magnetite (sometimes magnesian - magnomagnetite, often martitized - turned into hematite during oxidation). They are most characteristic of carbonatite, skarn and hydrothermal deposits. Apatite and baddeleyite are extracted from carbonatite deposits, and cobalt-containing pyrite and non-ferrous metal sulfides are extracted from skarn deposits. A special variety of magnetite ores are complex (Fe-Ti-V) titanomagnetite ores of igneous deposits. Hematite ores, composed mainly of hematite and, to a lesser extent, magnetite, are common in the weathering crust of ferruginous quartzites (martite ores), in skarn, hydrothermal, and volcanogenic-sedimentary ores. Rich hematite ores contain 55-65% Fe and up to 15-18% Mn. Siderite ores are subdivided into crystalline siderite ores and clayey spar iron ore; they are often magnesian (magnosiderites). They are found in hydrothermal, sedimentary and volcanic-sedimentary deposits. The average content of Fe in them is 30-35%. After roasting siderite ores, as a result of removing CO 2, finely porous iron oxide concentrates are obtained containing 1-2%, sometimes up to 10% Mn. In the oxidation zone, siderite ores turn into brown iron ore. Silicate iron ores are composed of ferruginous chlorites (, leptochlorite, etc.), accompanied by iron hydroxides, sometimes. They form sedimentary deposits. The average content of Fe in them is 25-40%. The admixture of sulfur is negligible, phosphorus up to 1%. They often have an oolitic texture. In the weathering crust, they turn into brown, sometimes red (hydrohematite) iron ore. Brown ironstones are composed of iron hydroxides, most often hydrogoethite. They form sedimentary deposits (marine and continental) and weathering crust deposits. Sedimentary ores often have an oolitic texture. The average content of Fe in ores is 30-35%. The brown iron ore of some deposits (Bakalskoye in the USSR, Bilbao in Spain, etc.) contains up to 1-2% Mn or more. Naturally alloyed brown iron ore, formed in the weathering crusts of ultramafic rocks, contains 32-48% Fe, up to 1% Ni, up to 2% Cr, hundredths of a percent Co, V. Chromium-nickel cast irons and low-alloy steel are smelted from such ores without additives. ( , ferruginous ) - poor and medium iron content (12-36%) metamorphosed iron ores, composed of thin alternating quartz, magnetite, hematite, magnetite-hematite and siderite interlayers, in places with an admixture of silicates and carbonates. They are distinguished by a low content of harmful impurities (S and R are hundredths of a percent). Deposits of this type usually have unique (over 10 billion tons) or large (over 1 billion tons) ore reserves. Silica is carried out in the weathering crust, and large deposits of rich hematite-martite ores appear.

The largest reserves and volumes of production fall on Precambrian ferruginous quartzites and rich iron ores formed from them, sedimentary brown iron ores, as well as skarn, hydrothermal and carbonatite magnetite ores, are less common.

Iron ore enrichment

There are rich (over 50% Fe) and poor (less than 25% Fe) ores that require. For qualitative characterization of rich ores importance has the content and ratio of non-metallic impurities (slag-forming components), expressed by the coefficient of basicity and flint modulus. According to the value of the basicity coefficient (the ratio of the sum of the contents of calcium and magnesium oxides to the sum of silicon oxides and ) iron ores and their concentrates are divided into acidic (less than 0.7), self-fluxing (0.7-1.1) and basic (more than 1.1 ). Self-fluxing ores are the best: acidic ores require the introduction of an increased amount of limestone (flux) into the blast-furnace charge compared to basic ones. According to the silicon module (the ratio of silicon oxide to aluminum oxide), the use of iron ores is limited to types of ores with a module below 2. Poor ores that require enrichment include titanomagnetite, magnetite, and also magnetite quartzites with a magnetite Fe content of over 10-20%; martite, hematite and hematite quartzites with Fe content over 30%; siderite, hydrogoethite and hydrogoethite-leptochlorite ores with Fe content over 25%. The lower limit of the total Fe and magnetite content for each deposit, taking into account its scale, mining and economic conditions, is set by the standards.

Ores that require enrichment are divided into easily enriched and difficult enriched, which depends on their mineral composition and textural and structural features. Easily enriched ores include magnetite ores and magnetite quartz, hard-enriched ores - iron ores, in which iron is associated with cryptocrystalline and colloidal formations, when crushed, it is not possible to reveal ore minerals in them due to their extremely small size and fine germination with non-metallic minerals. The choice of enrichment methods is determined by the mineral composition of ores, their textural and structural features, as well as the nature of non-metallic minerals and the physical and mechanical properties of ores. Magnetite ores are enriched by the magnetic method. The use of dry and wet magnetic separation ensures the production of conditioned concentrates even with a relatively low iron content in the original ore. If there are commercial grades of hematite in the ores, magnetic-flotation (for finely disseminated ores) or magnetic-gravity (for coarsely disseminated ores) beneficiation methods are used along with magnetite. If magnetite ores contain industrial quantities of apatite or sulfides, copper and zinc, boron minerals and others, then flotation is used to extract them from magnetic separation waste. The enrichment schemes for titanomagnetite and ilmenite-titanomagnetite ores include multi-stage wet magnetic separation. In order to isolate ilmenite into titanium concentrate, wet magnetic separation waste is enriched by flotation or gravity, followed by magnetic separation in a high-intensity field.

Enrichment schemes for magnetite quartzites include crushing, grinding, and low-field magnetic enrichment. Enrichment of oxidized ferruginous quartzites can be carried out by magnetic (in a strong field), roasting magnetic and flotation methods. For enrichment of hydrogoethite-leptochlorite oolitic brown iron ore, a gravitational or gravitational-magnetic (in a strong field) method is used; research is also underway to enrich these ores by roasting a magnetic method. Clayey hydrogoethite and (pebble) ores are enriched by washing. Enrichment of siderite ores is usually achieved by roasting. During the processing of ferruginous quartzites and skarn-magnetite ores, concentrates with an Fe content of 62-66% are usually obtained; in conditioned concentrates of wet magnetic separation from apatite-magnetite and magnomagnetite iron ores, not less than 62-64%; for the electrometallurgical processing, concentrates are produced with an Fe content of not less than 69.5%, SiO 2 not more than 2.5%. Concentrates of gravitational and gravitational-magnetic enrichment of oolitic brown iron ore are considered conditioned when the content of Fe is 48-49%; as enrichment methods improve, the requirements for concentrates from ores increase.

Most of the iron ores are used for iron smelting. A small amount serves as natural paints (ocher) and weighting agents for drilling muds.

Iron ore reserves

In terms of iron ore reserves (balance - over 100 billion tons), the CCCP ranks first in the world. The largest iron ore reserves in the USSR are concentrated in Ukraine, in central regions RSFSR, in Northern Kazakhstan, in the Urals, in western and eastern Siberia. From total of explored reserves of iron ores 15% - rich, not requiring enrichment, 67% - enriched by simple magnetic schemes, 18% - requiring complex enrichment methods.

KHP , North Korea and CPB have significant reserves of iron ore, sufficient to develop their own ferrous metallurgy. see also

Thanks to their unique properties- malleability, strength, ductility - the metal is widely used by any industry around the world. The raw materials for its manufacture are iron-containing minerals.

Reserves in the world

There are deposits of iron-bearing minerals on every continent. Their resources are distributed as follows (in descending order):

• European states.
• Asian countries.
• African continent: South Africa, Algeria, Liberia, Zimbabwe, Angola, Gabon.
• South and North America.

Iron ore deposits have been discovered in the territories of 98 states. Today, their real figure is 212 billion tons. But scientists believe that the world's deposits of this strategic raw material can amount to 790 billion tons.

In percentage terms, iron ore reserves by country are distributed as follows:

• Ukraine - 18%.
• Russia - 16%.
• Brazil - 13%.
• Australia - 11%.
• China - 13%.
• India - 4%.
• The rest - 25%.

Ore beds differ in iron content. They are rich (more than 50% Fe), ordinary (25–50%), poor (less than 25%). Therefore, in terms of iron content, their reserves are distributed differently:

• Russia - 19%.
• Brazil - 18%.
• Australia - 14%.
• Ukraine - 11%.
• China - 9%.
• India - 4%.
• The rest - 25%.

Of all mined iron minerals, 87% have low quality(iron content 16–40%). Such raw materials require enrichment. Russia extracts only 12% of high quality ferrous compounds, with an iron content of more than 60%. The highest quality raw materials for metallurgy are mined on the Australian mainland (64% Fe).

It is calculated that at current level ore extraction, the supply of iron to the world economy will be 250 years.

The largest deposits

Of all the countries in the world, the richest reserves of iron ore in Russian Federation. They are concentrated in several regions.

Kursk magnetic anomaly. This is a huge iron ore region of the world scale. There are several powerful deposits here. One of them - Lebedinskoye (14.6 billion tons) - was twice entered into the Guinness Book of Records for its size and output.

As well as less wealthy regions:

• Ural.
• Kola ore region.
• Karelia.
• Western Siberia.

In addition to Russia, large deposits are located on the territory of:

• Australia (Iron Knob, West Australian).
• USA (Verkhneozernoe).
• Canada (Newfoundland, Labrador).
• South Africa (Transvaal).
• India (Singbhum).
• Sweden (Mount Kirunavaare).
• China (near the city of Anshan).

Ukraine has significant reserves of iron ore - more than 21 billion tons. There are 3 deposits here - Krivorozhskoye, Beloretskoye and Kremenchugskoye. The latter has deposits with low iron content. In addition, they contain many harmful impurities. The other two deposits produce high quality iron ore.

Rich iron compounds (up to 68% Fe) are mined in Venezuela. The country's resource is 2,200 million tons. The Brazilian deposits of Carajas and Urukum contain more than ten billion tons of rich deposits (50–69% Fe). About 3,000 million tons of ordinary brown iron ore lies on about. Cuba.

In the USA there are huge deposits of ferruginous quartzites, which require thorough enrichment.

Ranking of countries in the world by iron ore production for 2017

Ore mining is carried out on the territory of more than 50 states. The industry leaders are China, Australia, Brazil, Russia, India. Together they extract 80% of all iron-bearing minerals.

From year to year, the volume of the iron mining industry is increasing all over the world, but they do not fully cover the needs of mankind. Many countries with developed mining and metallurgical industries lack their own resources of iron ore, and they are forced to purchase it abroad.

The largest importers are South Korea, Japan, USA, EU countries. Even the Celestial Empire - a republic that ranks first in the world in terms of ore mining - is forced to import it. Australia, Brazil and India export the most iron ore raw materials.

To imagine how the iron ore industry is developing, it is presented comparison table by ore extraction per year (million tons):

There has been a steady growth in the Indian iron ore industry. It is expected that by 2020 its performance will increase by 35%.

Among all the mining companies in the world, 3 ore giants occupy a fundamental place:

• BHP Billiton, the largest Australian-British company.
• Vale S.A. (Brazilian company).
• Rio Tinto, a multinational corporation.

They mine in many states, own power plants, iron ore enrichment plants and steel smelting, carry out rail and sea transportation with their own transport, set world prices for raw materials.

Iron ore are a special mineral formation, including iron, as well as its compounds. An ore is considered iron ore if it contains this element in sufficient volumes to make it economically profitable to extract it.

The main variety of iron ore is magnetic iron ore. It contains almost 70% oxide and ferrous oxide. This ore is black or steel grey. on the territory of Russia, they are mined in the Urals. It is found in the depths of High, Grace and Kachkanar. In Sweden, it is found in the vicinity of Falun, Dannemor and Gellivar. In the US, this is Pennsylvania, and in Norway, Arendal and Persberg.

In ferrous metallurgy, iron ore products are divided into three types:

Separated iron ore(low in iron);

Sinter ore (with an average iron content);

Pellets (crude iron-containing mass).

Morphological types

Iron ore deposits are considered rich if they contain more than 57% iron in their composition. Poor ores include those in which at least 26% iron. Scientists divided iron ore into two morphological types: linear and flat-like.

Iron ore linear type represents ore wedge-shaped bodies in the zones of bends and earth faults. This type is distinguished by a particularly high iron content (from 50 to 69%), but sulfur and phosphorus are contained in such ore in small quantities.

Flat-like deposits occur on the tops of ferruginous quartzites, which represent a typical weathering crust.

Iron ore. Application and extraction

Rich iron ore is used to produce pig iron and is mainly used for smelting in converter and open-hearth production or directly for the reduction of iron. A small amount is used as a natural paint (ocher) and weighting agent for clay

The volume of world reserves of explored deposits is 160 billion tons, and they contain about 80 billion tons of iron. Iron ore was found in Ukraine, and the largest reserves pure iron have Russia and Brazil.

The volume of world ore mining is growing every year. In most cases, iron ore is mined by an open method, the essence of which is that all the necessary equipment is delivered to the deposit, and a quarry is built there. The depth of the quarry is on average about 500 m, and its diameter depends on the features of the found deposit. After that, with the help of special equipment, iron ore is mined, stacked on vehicles adapted to transport heavy loads, and delivered from the quarry to enterprises that are engaged in processing.

The disadvantage of the open method is the ability to extract ore only at shallow depths. If it lies much deeper, you have to build mines. First, a trunk is made that resembles a deep well with well-fortified walls. Corridors, the so-called drifts, depart from the trunk in different directions. The ore found in them is blown up, and then its pieces are raised to the surface with the help of special equipment. The extraction of iron ore in this way is efficient, but involves serious danger and cost.

There is another method by which iron ore is mined. It is called SHD or borehole hydraulic production. Ore is extracted from underground in this way: a well is drilled, pipes with a hydraulic monitor are lowered into it and the rock is crushed with a very powerful water jet, which is then raised to the surface. The extraction of iron ore in this way is safe, but, unfortunately, inefficient. Only 3% of the ore can be mined this way, and 70% is mined using mines. However, the development of the SHD method is being improved, and there is a high probability that in the future this option will become the main one, displacing mines and quarries.