Mercury. Properties of mercury

Perhaps mercury is one of the few chemical elements that has a lot of interesting properties, as well as the widest scope of application in the entire history of mankind. Here are just a few Interesting Facts about this chemical element.

First of all, mercury is the only metal and the second substance (along with bromine) that remains in a liquid state at room temperature. It becomes solid only at a temperature of –39 degrees. But raising it to +356 degrees causes the mercury to boil and turn into toxic steam. Due to its density it has a large specific gravity(see article The heaviest metals in the world). So, 1 liter of the substance weighs more than 13 kilograms.

Cast iron core floats in mercury

In nature, it can be found in its pure form - interspersed with small drops in other rocks. But most often mercury was extracted by burning the mercury mineral cinnabar. Also, the presence of mercury can be found in sulfide minerals, shales, etc.

Thanks to its color ancient times this metal was even identified with living silver, as evidenced by one of its Latin names: argentum vivum. And this is no wonder, because being in its natural state - liquid, it is able to “run” faster than water.

Due to its excellent electrical conductivity, mercury is widely used in the manufacture of lighting fixtures and switches. But mercury salts are used in the manufacture of various substances, from antiseptics to explosives.

Humanity has been using mercury for more than 3,000 years. Due to its toxicity, it was actively used by ancient chemists to extract gold, silver, platinum and other metals from ore. This method, called amalgatation, was later forgotten and was returned to only in the 16th century. Perhaps it was thanks to him that the colonialists mined gold and silver South America at one time reached colossal proportions.

A special place in the use of mercury in the Middle Ages was its use in mystical rituals. Sprayed red cinnabar powder, according to shamans and magicians, was supposed to scare away evil spirits. “Living silver” was also used to extract gold alchemically.

But mercury became a metal only in 1759, when Mikhail Lomonosov and Joseph Brown were able to prove this fact.

Despite its toxicity, mercury was actively used by ancient healers in the treatment of various diseases. Based on it, medications and potions were made to treat various skin diseases. It was part of diuretics and laxatives and was used in dentistry. And yoga ancient india, according to the notes of Marco Polo, they drank a drink based on sulfur and mercury, which extended their life and gave them strength. There are also known cases of Chinese healers making “immortality pills” based on this metal.

In medical practice, there are known cases of using mercury in the treatment of volvulus. According to doctors of those times, thanks to their physical properties“liquid silver” had to pass through the intestines, straightening them. But this method did not take root, as it had very disastrous results - patients died from intestinal rupture.

Today in medicine, mercury can only be found in thermometers that measure body temperature. But even in this niche it is gradually being replaced by electronics.

But despite the attributed beneficial properties, mercury also has destructive properties on the human body. So, according to scientists, the Russian Tsar Ivan the Terrible became a victim of mercury “treatment”. During the exhumation of his remains, modern experts established that the Russian sovereign died as a result of mercury intoxication, which he received during treatment for syphilis.

The use of mercury salts was also disastrous for medieval hat makers. Gradual poisoning by mercury vapor became the cause of dementia, called the mad hatter's disease. This fact was reflected in Lewis Carroll's Alice in Wonderland. The author perfectly depicted this illness in the image of the Mad Hatter.

But using mercury for the purpose of suicide, on the contrary, was not successful. There are known facts when people drank it or made intravenous mercury injections. And they all remained alive.

Uses of mercury

IN modern world mercury has found wide application in electronics, where components based on it are used in all kinds of lamps and other electrical equipment; it is used in medicine for the production of certain drugs and in agriculture when processing seeds. Mercury is used to produce paint that is used to paint ships. The fact is that colonies of bacteria and microorganisms can form on the underwater part of the ship, which destroy the hull. Mercury-based paint prevents this destructive effect. This metal is also used in oil refining to regulate the temperature of the process.

But scientists don't stop there. Today is held big job on studying beneficial properties of this metal with its subsequent use in mechanics and the chemical industry.

Mercury: 7 Quick Facts

1. Mercury is the only metal that normal conditions is in a liquid state.
2. It is possible to make alloys of mercury with all metals except iron and platinum.
3. Mercury is a very heavy metal because... has enormous density. For example, 1 liter of mercury has a mass of about 14 kg.
4. Metallic mercury is not as poisonous as is commonly believed. The most dangerous are mercury vapor and its soluble compounds. Metallic mercury itself is not absorbed into gastrointestinal tract and is excreted from the body.
5. Mercury cannot be transported on airplanes. But not because of its toxicity, as it might seem at first glance. The thing is that mercury, in contact with aluminum alloys, makes them brittle. Therefore, an accidental spill of mercury can damage the aircraft.
6. The ability of mercury to expand uniformly when heated was found wide application V various kinds thermometers.
7. Remember the Mad Hatter from Alice in Wonderland? So before, such “hatters” actually existed. The thing is that the felt used to make hats was treated with mercury compounds. Gradually, mercury accumulated in the master’s body, and one of the symptoms of mercury poisoning is severe mental disorder; in other words, hatters often ended up going crazy.

Mercury

MERCURY-And; and. Chemical element (Hg), a liquid heavy metal with a silvery-white color (widely used in chemistry and electrical engineering). Alive like mercury.(very mobile).

◊ Mercury fulminate An explosive substance in the form of a white or gray powder.

(lat. Hydrargyrum), chemical element Group II periodic table. Silver liquid metal(from here Latin name; from Greek hýdōr - water and árgyros - silver). Density at 20°C 13.546 g/cm 3 (heavier than all known liquids), t pl –38.87°C, t bale 356.58°C. Mercury vapor at high temperatures and at electrical discharge emit a bluish-green light rich in ultraviolet rays. Chemically resistant. The main mineral is cinnabar HgS; Native mercury is also found. Used in the manufacture of thermometers, pressure gauges, gas-discharge devices, in the production of chlorine and sodium hydroxide (as a cathode). Alloys of mercury with metals - amalgams. Mercury and many of its compounds are poisonous.

MERCURY (lat. Hydrargyrum), Hg (read “hydrargyrum”), chemical element with atomic number 80, atomic mass 200.59.
Natural mercury consists of a mixture of seven stable nuclides: 196 Hg (content 0.146% by weight), 198 Hg (10.02%), 199 Hg (16.84%), 200 Hg (23.13%), 201 Hg (13 .22%), 202 Hg (29.80%) and 204 Hg (6.85%). The radius of a mercury atom is 0.155 nm. Radius of Hg + ion - 0.111 nm (coordination number 3), 0.133 nm (coordination number 6), Hg 2+ ion - 0.083 nm (coordination number 2), 0.110 nm (coordination number 4), 0.116 nm (coordination number 6) or 0.128 nm (coordination number 8). The sequential ionization energies of a neutral mercury atom are 10.438, 18.756, and 34.2 eV. Located in group IIB, period 6 of the periodic table. Configuration of outer and pre-outer electronic layers 5 s 2 p 6 d 10 6s 2 . In compounds it exhibits oxidation states +1 and +2. Electronegativity according to Pauling (cm. PAULING Linus) 1,9.
History of discovery
Mercury has been known to mankind since ancient times. Cinnabar firing (cm. CINNABAR) HgS, leading to the production of liquid mercury, was used as early as the 5th century. BC e. in Mesopotamia (cm. MESOPOTAMIA). The use of cinnabar and liquid mercury is described in ancient documents from China and the Middle East. First detailed description the preparation of mercury from cinnabar is described by Theophrastus (cm. THEOPHRAST) about 300 BC e.
In ancient times, mercury was used to mine gold (cm. GOLD (chemical element)) from gold ores. This method is based on its ability to dissolve many metals, forming liquid or fusible amalgams (cm. AMALGAM). When the gold amalgam is calcined, the volatile mercury evaporates, leaving the gold behind. In the second half of the 15th century, amalgamation was used in Mexico to extract silver from ore (cm. SILVER).
Alchemists considered mercury integral part all metals, believing that by changing its content it is possible to transform mercury into gold. Only in the 20th century. physicists have found that in the process nuclear reaction mercury atoms actually turn into gold atoms. But this method is extremely expensive.
Liquid mercury is a very mobile liquid. Alchemists called mercury “mercury” after the Roman god Mercury, famous for his speed in movement. In English, French, Spanish and Italian The name "mercury" is used for mercury. The modern Latin name comes from the Greek words “hudor” - water and “argyros” - silver, i.e. “liquid silver”.
Mercury preparations were used in medicine in the Middle Ages (iatrochemistry (cm. IATROCHEMISTRY)).
Being in nature
Rare trace element. The mercury content in the earth's crust is 7.0·10–6% by mass. In nature, mercury occurs in a free state. Forms more than 30 minerals. The main ore mineral is cinnabar. Mercury minerals in the form of isomorphic impurities are found in quartz, chalcedony, carbonates, mica, and lead-zinc ores. The yellow modification of HgO occurs in nature as the mineral montroidite. Participates in the metabolic processes of the lithosphere, hydrosphere, and atmosphere a large number of mercury The mercury content in ores ranges from 0.05 to 6-7%.
Receipt
Mercury was originally obtained from cinnabar (cm. CINNABAR), placing pieces of it in bundles of brushwood and burning cinnabar in fires.
Currently, mercury is produced by redox roasting of ores or concentrates at 700-800 o C in fluidized bed furnaces, tubular or muffle. Conventionally, the process can be expressed:
HgS + O 2 = Hg + SO 2
The yield of mercury with this method is about 80%. A more efficient way to obtain mercury is by heating ore with Fe (cm. IRON) and CaO:
HgS + Fe = Hg – + FeS,
4HgS + 4CaO = 4Hg – + 3CaS + CaSO 4.
Particularly pure mercury is obtained by electrochemical refining on a mercury electrode. In this case, the impurity content ranges from 1·10–6 to 1·10–7%.
Physical and chemical properties
Mercury is a silvery-white metal, colorless in vapor. The only metal that is liquid at room temperature. Melting point –38.87°C, boiling point 356.58°C. The density of liquid mercury at 20°C is 13.5457 g/cm 3 , solid mercury at –38.9°C is 14.193 g/cm 3 .
Solid mercury is colorless crystals of octahedral shape, existing in two crystalline modifications. The “high-temperature” modification has a rhombohedral a-Hg lattice, the parameters of its unit cell (at 78 K) are a = 0.29925 nm, angle b = 70.74 o. The low-temperature modification b-Hg has a tetragonal lattice (below 79K).
Using mercury, the Dutch physicist and chemist H. Kamerlingh-Onnes (cm. KAMERLING-ONNES Heike) in 1911 he first observed the phenomenon of superconductivity (cm. SUPERCONDUCTIVITY). The transition temperature of a-Hg to the superconducting state is 4.153K, b-Hg - 3.949K. With more high temperatures mercury behaves like a diamagnetic (cm. DIAMAGNETIC). Liquid mercury does not wet glass and is practically insoluble in water (6·10–6 g of mercury dissolves in 100 g of water at 25°C).
Standard electrode potential of the Hg 2+ 2 /Hg 0 pair = +0.789 V, the Hg 2+ /Hg 0 pair = +0.854 V, the Hg 2+ /Hg 2+ 2 pair = +0.920 V. Mercury does not dissolve in non-oxidizing acids, releasing hydrogen. (cm. HYDROGEN). (cm. OXYGEN)
Oxygen (cm. OXYGEN) and dry air under normal conditions do not oxidize mercury. Wet air and oxygen under ultraviolet irradiation or electron bombardment oxidize mercury from the surface to form oxides.
Mercury is oxidized by atmospheric oxygen at temperatures above 300°C, forming red mercuric oxide HgO:
2Hg + O 2 = 2HgO.
Above 340°C this oxide decomposes into simple substances.
At room temperature, mercury is oxidized by ozone (cm. OZONE).
Mercury does not react under normal conditions with molecular hydrogen, but with atomic hydrogen it forms the gaseous hydride HgH. Mercury does not interact with nitrogen, phosphorus, arsenic, carbon, silicon, boron, and germanium.
Mercury does not react with dilute acids, but dissolves in aqua regia (cm. AQUA REGIA) and in nitric acid. Moreover, in the case of acid, the reaction product depends on the concentration of the acid and the ratio of mercury to acid. When there is an excess of mercury in the cold, the reaction occurs:
6Hg + 8HNO 3 dil. = 3Hg 2 (NO 3) 2 + 2NO + 4H 2 O.
If there is excess acid:
3Hg + 8HNO 3 = 3Hg(NO 3) 2 + 2NO + 4H 2 O.
With halogens (cm. HALOGEN) mercury actively interacts with the formation of halides (cm. HALOGENIDES). In reactions of mercury with sulfur (cm. SULFUR), selenium (cm. SELENIUM) and tellurium (cm. TELLURIUM) chalcogenides arise (cm. CHALCOGENIDES) HgS, HgSe, HgTe. These chalcogenides are practically insoluble in water. For example, the PR value of HgS = 2·10 –52. Mercury sulfide dissolves only in boiling HCl, aqua regia (this forms complex 2–) and in concentrated solutions of alkali metal sulfides:
HgS + K 2 S = K 2 .
Alloys of mercury with metals are called amalgams (cm. AMALGAM). Amalgamation-resistant metals - iron (cm. IRON), vanadium (cm. VANADIUM), molybdenum (cm. MOLYBDENUM), tungsten (cm. TUNGSTEN), niobium (cm. NIOBIUM) and tantalum (cm. TANTALUM (chemical element)). With many metals, mercury forms intermetallic compounds, mercurides.
Mercury forms two oxides: mercury(II) oxide HgO and mercury(I) oxide Hg 2 O, which is unstable in light and when heated (black crystals).
HgO forms two modifications - yellow and red, differing in crystal sizes. The red modification is formed when alkali is added to a solution of Hg 2+ salt:
Hg(NO 3) 2 + 2NaOH = HgOЇ + 2NaNO 3 + H 2 O.
The yellow form is chemically more active and turns red when heated. The red form turns black when heated, but returns to its original color when cooled.
When alkali is added to a solution of mercury(I) salt, mercury(I) oxide Hg 2 O is formed:
Hg 2 (NO 3) 2 + 2NaOH = Hg 2 O + H 2 O + 2NaNO 3.
In the light, Hg 2 O decomposes into mercury and HgO, giving a black precipitate.
Mercury(II) compounds are characterized by the formation of stable complex compounds (cm. COMPLEX CONNECTIONS):
2KI + HgI 2 = K 2,
2KCN + Hg(CN) 2 = K 2 .
Mercury(I) salts contain the Hg 2 2+ group with the –Hg–Hg– bond. These compounds are obtained by reducing mercury(II) salts with mercury:
HgSO 4 + Hg + 2NaCl = Hg 2 Cl 2 + Na 2 SO 4,
HgCl 2 + Hg = Hg 2 Cl 2.
Depending on the conditions, mercury(I) compounds can exhibit both oxidizing and reducing properties:
Hg 2 Cl 2 + Cl 2 = 2HgCl 2,
Hg 2 Cl 2 + SnCl 2 = 2Hg + SnCl 4. (cm. PEROXIDE COMPOUNDS)
Peroxide (cm. PEROXIDE COMPOUNDS) HgO 2 - crystals; unstable, explodes when heated and impacted.
Application
Mercury is used for the manufacture of cathodes for the electrochemical production of caustic alkalis and chlorine, as well as for polarographs, in diffusion pumps, barometers and pressure gauges; to determine the purity of fluorine and its concentration in gases. The bulbs of gas-discharge lamps (mercury and fluorescent) and UV radiation sources are filled with mercury vapor. Mercury is used in gold plating and in the extraction of gold from ore. ( cm. )
Sulema ( cm.) - the most important antiseptic, used at dilutions of 1:1000. Mercury (II) oxide, cinnabar HgS are used to treat eye, skin and venereal diseases. Cinnabar is also used to make ink and paints. In ancient times, blush was made from cinnabar. Calomel (cm. CALOMEL) used in veterinary medicine as a laxative.
Physiological action
Mercury and its compounds are highly toxic. Mercury vapors and compounds accumulate in the human body, are absorbed by the lungs, enter the blood, disrupt metabolism and infect nervous system. Signs of mercury poisoning appear already at mercury concentrations of 0.0002–0.0003 mg/l. Mercury vapor is phytotoxic and accelerates the aging of plants.
When working with mercury and its compounds, it should be prevented from entering the body through the respiratory tract and skin. Store in closed containers.

encyclopedic Dictionary. 2009 .

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Mercury, and... Russian spelling dictionary

Mercury/ … Morphemic-spelling dictionary

MERCURY, Hydrargyrum (from the Greek hydor water and argyros silver), Mercurium, Hydrargyrum VIvum, s. metallicum, Mercurius VIvus, Argentum VIvum, silvery-white liquid metal, symbol. Hg, at. V. 200.61; beat V. 13.573; at. volume 15.4; t° frozen.… … Great Medical Encyclopedia

Mercury deposits are known in more than 40 countries around the world. World mercury resources are estimated at 715 thousand tons, quantitatively accounted reserves are 324 thousand tons, of which 26% are concentrated in Spain, 13% each in Kyrgyzstan and Russia, 8% in Ukraine, approximately 5-6.5% each - in Slovakia, Slovenia, China, Algeria, Morocco, Turkey. The supply of mercury reserves to the maximum level of its consumption, reached in the 1990s, is about 80 years for the world. Since the early 1970s. because of environmental factors The mercury market situation began to deteriorate noticeably. If in the early 1970s. world production primary mercury (mining and smelting) was estimated at 10,000 tons per year, then by the end of the 1980s. it has more than doubled. This was accompanied by a decrease in mercury prices: from 11 -12 thousand US dollars per 1 ton in 1980-1982. up to 4-5 thousand dollars in 1994-1996. Experts believe that this will not happen in the coming years sudden change mercury market conditions. In a number of industries, its use will slowly decline. However, in some industries, for various reasons, for example, in instrument making, electrical engineering, and the defense industry, mercury consumption will apparently remain at the same level. The chemical industry of a number of countries, associated with the production of chlorine, caustic soda, acetaldehyde, and vinyl chloride using the mercury method, will also remain an important consumer of this metal. There are similar enterprises in Russia.

Mercury has always been widely used in various areas of practical, scientific and cultural human activity. By the beginning of the 1980s. over a thousand different areas of its application were known. Here are the main ones in which mercury and its compounds are still used to one degree or another: - chemical industry- production of chlorine and caustic soda, acetaldehyde, vinyl chloride, polyurethanes, organomercury pesticides, paints;

Electrical industry - production of various lamps, relays, dry batteries, switches, rectifiers, ignitrons, etc.;

Radio engineering industry and instrument making - production of control and measuring instruments (thermometers, barometers, pressure gauges, polarographs, electrometers), radio and television equipment;

Medicine and pharmaceutical industry - production of eye and skin ointments, bactericidal substances, production of vitamin B, production of dental fillings (silver and copper amalgam);

Agriculture (pesticides, antiseptics);

Mechanical engineering and vacuum technology - production of vacuum pumps, etc.;

Military science - production of detonators, guided missiles;

Metallurgy - production of ultrapure metals, precision casting, amalgamation of precious metals;

Mining (mercury fulminate);

Laboratory practice and analytical chemistry.

In the energy sector, mercury was used as a working fluid in powerful industrial-type binary plants, where mercury-steam turbines were used to generate electricity in the first stages, as well as in nuclear reactors for heat removal. Elemental mercury is used in lithium isotope separation processes. Mercury is sometimes alloyed with other metals. Small additions of it increase the hardness of the lead alloy with alkaline earth metals. It was even used for soldering. Mercury cyanide was used in the production of antiseptic soap.

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Currently, in Russia, the State Balance of Mineral Reserves includes 24 mercury deposits. Most of them belong to mercury (cinnabar) proper with reserves, as a rule, of no more than 2 thousand tons of metal. Only four deposits are relatively large - Tamvatneyskoye (14 thousand tons), Zapadno-Palyanskoye (10.1 thousand tons), Chagan-Uzunskoye (14 thousand tons), Zvezdochka (3 thousand tons). The qualitative state of the mineral resource base of the domestic mercury industry is generally assessed as unsatisfactory, since the ores of most known deposits are characterized by low content mercury (significantly less than 1%). The only exceptions are the ores of the Zvezdochka, Balgikakchan, Chempurinskoye and Olyutorskoye deposits (Table 3).

Table 3. Regional structure of balance reserves of mercury in Russia

* Identified mercury reserves in Russia at the beginning of 2001 were estimated at 45.3 thousand tons, of which 15.6 thousand tons were industrial reserves.

** The average mercury content in ores of Russian deposits is estimated at 0.453% (the average mercury content in ores of deposits, for example, Spain reaches 1.9%, Algeria - 1.75%, Kyrgyzstan - 1%).

Potential production capacities for the production of primary mercury in Russia are available at the Aktash Mining and Metallurgical Enterprise (up to 150 tons/year) and CJSC NPP Kubantsvetmet (up to 25-30 tons/year). However, the small scale and low quality of mercury ores of the Sakhalin deposit (Krasnodar Territory), the almost complete absence of its own raw material base and organizational and financial reasons at the Aktash GMP (Altai Republic) do not give reason to hope for the resumption of mining operations at these sites. Potentially, the Aktash gas and treatment plant can process ores from the Sukor deposit located 90 km away. It is also known that more than 7 thousand tons of ore (about 6 tons of mercury) are stored near the metallurgical plant of CJSC NPP Kubantsvetmet, which is planned to be processed in the coming years; another 30 thousand tons of ore (about 25 tons of mercury) are located near the former mines and quarry of the Sakhalin deposit.

The development of large Tamvatneyskoye and Zapadno-Palyanskoye deposits (as well as many others) is impossible without significant investments, which - given the current situation on the world mercury market - are difficult to count on. In addition, their development may negatively affect, for example, spawning grounds valuable species fish, the state of the environment, etc. Moreover, given the scale of mercury-containing waste accumulated to date in Russia, there is no urgent need for the development of mercury deposits, since the domestic industry - with the implementation of certain measures - can be provided with secondary and associated mercury.

Thus, the State Balance of Mineral Reserves takes into account 3 mercury-containing copper-pyrite deposits - Podolskoye (Bashkortostan), Talganskoye (Chelyabinsk region), Safyanovskoye ( Sverdlovsk region) (see Table 4). The ores mined annually at the Safyanovskoe deposit contain up to 10 tons of mercury. Mercury is present in significant concentrations in ores of copper-pyrite, polymetallic, gold-silver and other types of deposits. However, with the technological schemes used in Russia for processing ores and concentrates of non-ferrous metals, associated mercury was not extracted, as it is not extracted now; a significant part of it is dissipated in environment and, for example, enters the sulfuric acid produced at some metallurgical plants. A significant amount of mercury goes into tailings at enrichment plants.

As noted above, in the 1980s. Associated mercury was obtained in small quantities from zinc concentrates at the Chelyabinsk zinc plant. On a more significant scale, mercury was extracted at the Khaidarkan plant from the antimony concentrate of the Anzor plant's enrichment plant. According to estimates, Russian non-ferrous metallurgy enterprises can produce up to 100 tons of associated mercury per year. According to the calculations of the author of these lines, in 2000-2003. with various raw materials (mainly concentrates and ores) into the metallurgical process at Russian factories non-ferrous metallurgy (zinc and blister copper smelting) received at least 60 tons of mercury annually.

Export of Russian mercury

In 1992-1998. Russia, as already noted, sold part of its mercury reserves on the world market. For example, in the mid-1990s. a significant share of Spanish imports was mercury from Russian warehouses: the Minas de Almaden company purchased it, refined it and resold it, including Russian enterprises. The dynamics of mercury exports by Russia to non-CIS countries looks approximately as follows (Table 4).

Table 4. Dynamics Russian exports mercury*

* In the annually published collections “Customs statistics of foreign trade Russian Federation» There is no direct information on the export and import of mercury.

** 120 tons of Russian mercury arrived in the United States.

*** From Russia to the USA, 79 tons were exported, but 120 tons of mercury were exported.

**** Mercury arrived in Rotterdam, where by May 1998 most of it was sold, and the remaining 276 tons were purchased by Minas de Almaden; According to data, 120 tons of mercury came from Russia to the United States.

***** However, mercury was exported in small volumes by Mercom LLC. There is information that a certain amount of mercury obtained from waste from the gold mining industry at one of the enterprises in the Irkutsk region in the early 2000s. was sold to China, and the Chelyabinsk zinc plant sends mercury sludge generated during zinc production for processing in Kyrgyzstan.

Data on imports of metallic mercury by Russia are sporadic: in 1997 - 30 tons, in 1998 - 46 tons, in 1999 - 11 tons. JSC Termopribor (Klin, Moscow Region) annually purchased approximately 15-20 tons of metallic mercury from Spain (from Minas de Almaden). In 2002, CJSC NPP Kubantsvetmet received 2,775 kg of substandard (rough, waste) mercury from Belarus (from Unitary Enterprise Beltsvetmet) for processing (refining).

The volume of world trade in mercury (export + import) in 1997 amounted to 7,600 tons. 29 countries exported mercury, of which only nine produced primary metal. Fifty-three countries imported mercury, with Hong Kong, China and the Netherlands accounting for almost half of total global imports (Hong Kong and the Netherlands mainly for resale). In 1999, world trade in mercury (exports + imports) amounted to more than 6128 tons.

It is interesting to note that in the 1990s. Estonia was among the mercury exporting countries (in 1977 - 35 tons, in 1998 - 17 tons). It is obvious that metal reserves were sold, or metallic mercury received in one way or another from Russia. It is significant that quite recently a clandestine storage facility containing 2.5 tons of mercury was discovered in Latvia.

The export of mercury will be completely banned in the European Union from March 2011 - this decision was made in 2008 by the EU Council of Ministers for Competition. This regulation, which also obliges EU states to ensure the safe storage of mercury residues, was adopted in order to reduce the volume of emissions of toxic types of heavy metals into the atmosphere.

BRIEF HISTORICAL INFORMATION. Mercury has been known since ancient times: it was mentioned by Aristotle and Theophrastus in 315 BC. e.; on an ancient relief map of China (210 BC), the ocean and rivers were filled with mercury. The Greek physician Dioscorides gave this metal the Latin name “hydrargium” (“silver water”) more than 2000 years ago. In the CIS, traces of the development of mercury ores were identified at the Khaidarkan mine (Great Mine), located in the Fergana Valley in Kyrgyzstan. Archaeological excavations have shown that mercury was mined for many centuries until the 13th century. (until the invasion of Genghis Khan). Ancient mine workings, tools, retorts for firing cinnabar have been preserved here, and even special bottles filled with mercury have been found.

Mercury under normal conditions is a silvery-white shiny liquid metal. At a temperature of about –38.86º C it hardens, and at a temperature of +353.6º C it boils. It was first obtained in the solid state in 1759.

GEOCHEMISTRY. Clarke of mercury 8.3·10 -6%. In nature, it is in a dispersed state and only 0.02% of it is concentrated in deposits. In igneous rocks of various compositions, the mercury content is close to clarke content, increasing in alkaline rocks to 1·10 -4 –1·10 -2%. Among sedimentary rocks, the maximum concentrations of mercury are found in clay shales (up to 2·10 -5%). In the waters of the World Ocean, the mercury content is 1·10 -6 g/l. There are seven known stable isotopes of mercury with mass numbers 196, 198–202 and 204, among which 202 Hg predominates. An important geochemical feature of mercury is that, among other chalcophile elements, it is characterized by the highest ionization potential. This determines such properties of mercury as the ability to be reduced to an atomic form (native mercury), significant chemical resistance to oxygen and acids.

According to many geologists, the source of juvenile mercury is subcrustal. Hydrothermal solutions containing Hg, Sb and As came from the mantle along deep faults. The transfer of mercury into them was carried out in the form of sulfide complexes (HgS 2-2), stable in alkaline solutions at low oxidation potential Eh. IN active volcanoes and thermal springs, mercury can migrate in the gas state and in the gas phase of hydrotherms.

In the hypergenesis zone, cinnabar and metallic mercury are soluble in water even in the absence of strong oxidizing agents. Mercury dissolves especially well in sulfides of caustic alkalis, forming, for example, the HgS nNa 2 S complex. It is easily sorbed by clays, iron and manganese hydroxides, shales and coals.

MINERALOGY. There are 25 minerals known to contain mercury, but those of industrial importance are cinnabar, metacinnabarite, native mercury, fahlore (schwatzite), corderoite, livingstonite and calomel.

Cinnabar HgS (Hg content 86.2%) crystallizes in a trigonal system, the crystal habit is rhombohedral, the aggregates are granular, disseminated, and powdery. The color of the mineral is bright and brownish-red, the luster is diamond-like, matte, hardness 2–2.5, specific gravity 8 g/cm3. It is found in mercury, mercury-antimony deposits, less often in gold-bearing quartz veins.

Metacinnabarite HgS (Hg 86.2%) crystallizes in the cubic system.

Native mercury Hg. Often contains Ag and Au impurities. Forms aggregates in the form of small drops, silver-white color, metallic luster, specific gravity at a temperature of 0º C 13.59 g/cm 3 .

Calomel Hg 2 Cl 2 (Hg 85%) crystallizes in a tetragonal system, the crystal habit is tabular. The color of the mineral is colorless, white to brown, hardness 1.5, specific gravity 7.27 g/cm 3 .

INDUSTRIAL APPLICATION. The use of mercury is based on its specific properties: at ordinary temperatures it is volatile; expands rapidly when heated; is capable of dissolving other metals, forming amalgams with Au, Ag, Pb, Zn, Al, Bi, and also emitting ultraviolet rays in a vapor state.

In the electrical and radio engineering industries, mercury is used in the manufacture of rectifiers, mercury interrupters, oscillators, mercury-quartz lamps, fluorescent lamps, etc. In medicine, mercury, its oxides and chloride salts are components various ointments, dental amalgams, etc. In the chemical industry, mercury is used in the production of chlorine and caustic soda, in the production of acetic acid from acetylene, and as a catalyst in the production of plastics. In the energy industry, it is used in mercury-steam boilers and turbines, in nuclear reactors (as a heat absorber), and in the gold mining industry to capture gold. In small quantities it is used in shipbuilding in the form of special paints, in the military industry and mining, in agriculture for seed treatment, etc.

RESOURCES AND RESERVES. Mercury resources are known in 40 countries, in 32 of them they are quantified and amount to 715 thousand tons. More than half of the world's mercury resources are concentrated in Europe, including 29% in Spain and 10% in Italy.

According to SNPP "Aerogeology" of the Ministry natural resources RF total mercury reserves were recorded in 18 countries and amounted to 324 thousand tons in 1997, of which 26% were concentrated in Spain, 13.5% in Kyrgyzstan and 13% in Russia.

Mercury is extracted from mercury, mercury-antimony, mercury-arsenic and mercury-gold, as well as incidentally from polymetallic, tungsten and tin ores. Rich ores contain more than 1% mercury, ordinary ores 1–0.2% and poor ores less than 0.2%. Currently, the quality of the mineral resource base of the global mercury industry is unsatisfactory. First of all, this concerns the quality of ores, which only in Spain and Algeria contain on average more than 1.5% Hg. In all other countries this figure does not exceed 0.55%. Such quality of ores at the current price level does not ensure their profitable mining, which was the main reason for the closure of many mines in the 1990s in Russia, Slovenia, Turkey, Slovakia and other countries.

According to metal reserves, unique deposits are distinguished - more than 100 thousand tons, very large 100-25 thousand tons, large 25-10 thousand tons, medium 10-3 thousand tons and small ones less than 3 thousand tons.

MINING AND PRODUCTION. Ore mining and primary mercury production in 1995–2000. carried out in 10 countries. Primary mercury production was 2.5–3.5 thousand tons. The bulk of world mercury production was concentrated in four countries: Spain - 27%, China - 19%, Kyrgyzstan - 15% and Algeria - 15%. These countries have the largest primary metal production capacities, due to which its level can be doubled if necessary.

In Spain, a state-owned company « Minas de Almaden y Arrayanes S. A.» (MAYASA) deliberately limits the production of mercury to maintain an acceptable price level on world markets. Information on mercury production in China is extremely limited. Production capacity in the country is estimated at 1.2–1.4 thousand tons of mercury per year. In Kyrgyzstan, several sections of the Khaidarkan field are being developed, as well as the smaller Chonkoy field. Over its more than half-century history, the Khaidarkan Mining and Metallurgical Plant produced more than 30 thousand tons of mercury. In 1995, this plant was transformed into a state joint-stock company "Khaidarkan Mercury State Joint Stock Co.” In Russia in 1970–1980. There were four to five small mines in the North Caucasus, Altai and Chukotka. Currently they are all closed.

METALLOGENY AND AGES OF ORE FORMATION. Mercury deposits are post-magnetic low-temperature hydrothermal formations that have a distant paragenetic connection with derivatives of deep subcrustal chambers of basaltoid magmatism.

Among the main mercury-bearing provinces, the most productive is the Mediterranean, which includes well-known deposits in Spain, Italy, Slovenia, Algeria and other countries. Mercury deposits appear in late orogenic stages of regional development and during periods of tectono-magmatic activation of consolidated geotectonic structures of different ages. They are localized along regional fault zones, traced in the peripheral parts of platforms and ancient middle massifs (Kolyma, Zeya-Bureinsky, etc.), as well as in the marginal parts of adjacent folded zones. The marginal parts of platforms are characterized by the development of gently sloping consonant ore deposits in strata of carbonate rocks, while the mineralized part of folded zones is more typical of cutting bodies and saddle deposits in the cores of anticlinal folds composed of sandstones and shales.

IN Precambrian And Early Paleozoic (Caledonian) era no industrial deposits of mercury were formed. TO Late Paleozoic (Hercynian) era include mercury deposits of Kyrgyzstan and Gorny Altai. The question of the age of mercury mineralization at the Nikitovskoe deposit in Ukraine remains controversial to this day. Some researchers consider it Late Paleozoic, others – Mesozoic. Only the lower age limit of mineralization has been reliably established, since it is confined to Middle Carboniferous sandstones occurring in the axial part of the Donetsk anticline. In the USA, in the Late Paleozoic, a number of relatively small mercury deposits were formed in the state of Arkansas. All are located along the southern border of the Mississippi Valley ore province.

IN Mesozoic era Significant mercury deposits have formed in various regions of the world. In China, most mercury deposits are confined to an extended belt located on the border of Hunan and Guizhou provinces. Mercury and antimony mineralization is not in visible connection with the Yanshan granites and is controlled by large fault zones. Mercury deposits, unlike antimony deposits, are more modest in size. In addition to cinnabar, the ores contain native mercury, stibnite, and less commonly metacinnabarite, realgar, orpiment, pyrite, and galena. Numerous mercury deposits and occurrences in Canada, concentrated in northwestern British Columbia, appear to be of Mesozoic age. Mercury mineralization is genetically associated with large granodiorite batholiths of the Coast Range of the Pacific coast, intruded in Post-Jurassic or Early Cretaceous times. The deposits are confined to a large fault traced along a strike of 200–250 km, which is accompanied by a brecciated zone up to 1.5 km wide. In the USA, a number of relatively small mercury deposits associated with Triassic and Jurassic rocks are known in the Humboldt and Pershing regions (Nevada).

In Russia, deposits of mercury ores have been identified in Chukotka, Western Verkhoyansk, and in the eastern regions of the Sakha Republic. The Zapadno-Palyanskoye deposit has been explored in Chukotka. Mercury stock-like mineralization is localized in zones of intersection of two fault systems and is represented by three deposits. There are a number of deposits in Western Verkhoyansk, among which the most studied is Zvezdochka.

IN Cenozoic era Most of the world's known mercury deposits were formed. Among them there are also deposits of Quaternary age (Monte Amiata in Italy; Sulfur Bank in the USA; thermal springs of Kamchatka, etc.). In the Balkans, the Idrija deposit, which has been developed for more than 450 years, is associated with Tertiary volcanism. In the United States, about 500 relatively small mercury deposits have been identified, concentrated within the Pacific ore belt. Mineralization is controlled by tectonic disturbances. The largest among them are New Almaden and New Idria. The ores have a high cinnabar content, sometimes reaching 10%. Mercury deposits are found in Mexico, Peru, and Bolivia. In North Africa, numerous deposits are confined to an extended fault along the slope of the Numidian ridge (Ras el-Ma, Mra-Sma, etc.).

GENETIC TYPES OF INDUSTRIAL DEPOSITS. Among the industrial deposits of mercury there are: 1) stratiform, 2) plutonogenic hydrothermal, 3) volcanogenic hydrothermal.

Stratiform deposits. They are known in Kyrgyzstan (Khaidarkan), the Republic of Sakha (Levosakynjin), Spain (Almaden), Peru (Huancavelica), China (Wanshan), and Ukraine (Nikitovskoe). They are distributed mainly in areas of stabilization of geosynclines or in zones of platform activation. These deposits are confined to terrigenous or carbonate complexes of rocks collected in folds, which are complicated by faults. Ore bodies are represented by conformable sheet-like deposits and lenses among porous sandstones or brecciated silicified limestones. The mercury content varies from 0.5–1 to 10–15%. The main ore mineral is cinnabar, the minor ones are metacinnabarite, stibnite, realgar, orpiment, marcasite, pyrite, livingstonite, arsenopyrite, galena, sphalerite, chalcopyrite. The process of mineral formation is long and proceeds over three to five stages.

The most typical representative of this type is Almaden field. It is located in Spain in the Sierra Morena mountains, 200 km southwest of Madrid. The ore-bearing area is composed of sandy-shale deposits, limestones and volcanic tuffs of the Silurian and Devonian, crushed into a series of anticlinal and synclinal folds. They are broken by faults, along some of which diabase dikes have intruded. Mercury mineralization is confined to three steeply dipping quartzite beds embedded in shales. The thickness of the terrigenous member with ore-bearing quartzites is 70 m, the length of the ore bodies along the strike is 250–300 m with a thickness of 2–14 m (on average 10 m). Vertically, mineralization is traced to a depth of 400 m. The main ore mineral is cinnabar, minor ones are native mercury, pyrite, chalcopyrite, metacinnabarite, etc. The mercury content in the ores is high (6–15%). The deposit has been exploited for more than 2000 years. Currently, the ores are mined at a depth of more than 300 m. The capacity of the Almaden enterprise, which includes several mines and a metallurgical plant, is 3.45–3.5 thousand tons of mercury per year. The total amount of mercury released at Almadney over the entire period of operation of the deposit is estimated at 260 thousand tons.

Plutonogenic hydrothermal deposits known in Russia (Barun-Shiveya and Ildikan in Transbaikalia), Ireland (Gortdrum), Turkey (Gumusler), China (Vosi), Tunisia (Jabel-Aja), USA (New Almaden, New Idriya). They occur among terrigenous, carbonate, igneous (granitoids, hyperbasites) and metamorphic rocks. Spatially associated with regional faults and fractured zones. Ore bodies have vein, lens-shaped, pipe-shaped, stockwork and nest-shaped shapes.

Plutonogenic hydrothermal deposits are represented by two ore formations: 1) quartz-chlorite-sericite-cinnabar(Gumusler, Barun-Shiveya) and 2) magnesia-carbonate-cinnabar(New Almaden and New Idriya in the USA, Chogan-Uzun in the Altai Mountains).

New Almaden field located in the Coast Range mountains 80 km northeast of San Francisco. It is confined to the contact of serpentinized peridotites with intensely dislocated Jurassic sandstones containing lenses of limestone and shales. Mineralization is confined to the apical parts of fragmented serpentinite massifs that have undergone hydrothermal metasomatic alteration, as a result of which the serpentinites are transformed into silicate-carbonate rock. Ore bodies are developed along fractures, fracture zones and crushing areas. They are randomly distributed along the apical part of the altered serpentinized massifs. The sizes of ore bodies range from small nests to relatively large deposits, stretching up to 300 m and having a width of 50–70 m with a thickness of 5 m. The mineral composition of the ores is relatively simple. Only cinnabar is of industrial importance. In addition, pyrite, chalcopyrite, stibnite, sphalerite, galena and bornite are found in small quantities. Vein minerals are represented by quartz and dolomite with spherical bitumen deposits. The average mercury content in ore is about 1%.

The deposit has been developed since 1824. In terms of the amount of metal extracted (from 1845 to 1926 – 34.5 thousand tons), it is second only to the Almaden, Idria and Huancavelica deposits. Due to depletion of reserves, its operation was discontinued. The mining depth of the deposit reached 820 m, where the ores turned out to be poor.

Volcanogenic hydrothermal deposits common in areas of modern or young volcanism and in areas of development thermal springs. They are known in Russia in Chukotka (Plamenoye), Kamchatka (Apapel, Chempura, Beloe, Alneyskoe), Italy (Monte Amiata), Algeria (Islaim), Turkey (Kazyzmakh), Japan (Itokuma), USA (Opalit, McDermit , Sulfur Bank, Cordero) and in other countries. The deposits are closely associated with andesitic, trachyliparitic and liparitic formations and are usually associated with lavas, tuffs, tuffites, extrusive, subvolcanic and vent facies, and less commonly with terrigenous carbonate rocks. They are often controlled by volcanogenic structures - calderas, volcano-tectonic depressions, volcanic domes, necks, synvolcanic ring faults, normal faults, thrusts and fracture zones. The composition of the ores is relatively complex. In addition to cinnabar, there are metacinnabarite, native mercury, calomel, corderoite, realgar, orpiment, stibnite, pyrite, marcasite, argentite, pyrargite, sphalerite, chalcopyrite, native gold and silver. Nonmetallic minerals include opal, sulfur, kaolinite, alunite, gypsum, barite, and less commonly zeolites, carbonates, and halloysite.

Monte Amiata field. This is one of the largest deposits belonging to the genetic type under consideration. Located in Italy in the province of Tuscany. The deposit area is composed of Upper Cretaceous limestones and shales, which are overlain by trachytes of the Quaternary volcano Monte Amiata (Fig. 16). It is confined to a fault-slip fault with a northeastern strike. The ore-bearing zone is composed of tectonic breccia located at the contact of sedimentary rocks and the Quaternary trachyte flow. The breccia deposit has been traced for 30 km in length and 10 km in width. It is cape-shaped and consists of mineralized blocks of crushed shale and limestone cemented by clayey material. In the ore-bearing zone, ore bodies are distinguished in the form of lenses (up to 5–10 m thick), nests and pipe-shaped bodies, traceable to a depth of 100–150 m. The mercury content in the upper horizons is 3–4%, in the lower ones – 1.5– 2.0%. The main ore mineral is cinnabar, the minor ones are realgar, orpiment, native sulfur and fluorite. During operation, more than 100 thousand tons of mercury were extracted from the field.