Extraction of gold from ore. How is gold mined? Mining process, mine development methods
In this article:
What can you get gold from and how to do it? This question has interested alchemists since time immemorial. Togo scientists time tried to turn into noble metal lead, iron and other elements that did not differ in nobility. Years and centuries passed, but the question is still relevant, the difference is that today getting gold at home is not a fantasy, but a reality.
What can you get Au from?
Getting gold at home is a difficult but exciting process. Some craftsmen manage not only to mine the precious metal without leaving their homes, but also to sell it at a very attractive price.
Gold in radio components
To make or, more precisely, it is possible from the following items:
- Details from a computer.
- TV or refrigerator.
- motherboards.
- mobile phones.
You can mine metal yourself from old radio components, computer parts, microcircuits and motherboards. Phones and even SIM cards are used, but the percentage of gold content in SIM cards is negligible.
To make it clearer, it is worth noting that the surface of some parts that are used in the manufacture of equipment is covered with gold. Jewelry that has been damaged or those whose surface is covered with gold can also be included in the work.
All products that are related to gilding and on the surface of which there is a layer of precious metal are suitable for processing.
IN mobile phones there is gold You will have to sort out the material that needs processing on your own. Sorting rules:
- parts are sorted by size;
- remove unnecessary elements;
- sort the material with a magnet.
Gold mining at home or, in other words, refining begins with sorting. Initially, the parts are sorted by size, laying them out into several piles.
If there are foreign elements on the surface of the products, then they are removed, this rule also applies to solder.
The last step is sorting the parts with a magnet. Separately set aside those that the magnet attracts, separating them from those that do not react to the magnet at all.
Since refining will be carried out at home, it is worth reducing costs. It is necessary to save reagents, sorting will just help to do this. Having finished sorting the parts, you can start making reagents.
In addition to evaporation, you can get the precious metal using the following elements:
- Mercury.
- Lead.
- Silver.
Mercury is converted to Au by the action of the sun. Adolf Mita somehow came up with the idea to experiment with minerals. He exposed them to a mercury lamp. Over time, a coating formed on the surface of the lamp, the chemist cleaned it off and analyzed it. There was gold in the raid.
Another Harvard scientist bombarded mercury nuclei with fast neutrons, during which Au was obtained. All experiments were carried out in the laboratory, not at home, but they were successful.
Lead turns into a noble metal for a long time. It happens under the influence of the sun. Analysis of lead showed that under the action of the light of the sun, the element becomes radioactive and changes over the years.
Silver is transformed into Au according to the Mexicans, who believed that if the vein found was held in the sun for several years, the silver would turn into a yellow metal. The discovery did not receive scientific confirmation, but newspapers wrote about it. So the method can be considered doubtful.
Evaporation can be done at home, but this will require reagents, without which the reaction will not take place.
Sequence and course of the procedure
You will have to make aqua regia - a mixture of hydrochloric and nitric acids in a ratio of one to three. The solution is made immediately before refining, since aqua regia loses its properties when cooked.
AU is inert, that is, it does not react with acids and alkalis. This property is inherent in all noble metals. not so easy, you can use mercury or aqua regia for this. Mercury forms a compound with gold, which is called an amalgam, an alloy of two metals. But the evaporation procedure can be considered the most cost-effective and less harmful.
How to mine gold at home using hydrochloric and nitric acids:
- you need to prepare a solution;
- put details in it;
- wait a bit;
- filter the solution.
The solution has a characteristic smell of chlorine. When immersing metals on the surface of which there is gold, it should be borne in mind that the reaction proceeds at different rates. The solution oxidizes metals and gold, but Au oxidizes more slowly.
Recovery of gold If the solution is heated, the reaction will accelerate; when the solution cools, gold is prone to recovery.
You won’t have to wait long: the gold will quickly separate from other elements and begin to float on the surface of the solution in the form of flakes.
When flakes appear, you need to filter the solution, do it with blue vitriol. Some amount of the precious metal will still remain in the compound.
The reagents used to carry out the reaction must be of high quality. If the expiration date of one of the components has expired, then refining may not work or the cost of its implementation will not pay off.
After adding vitriol to the solution, it is filtered through a cloth. It must be dense so that gold particles settle on its surface. After filtering, the metal must be washed to stop the reaction.
Since aqua regia releases chlorine during operation, it is worthwhile to carry out procedures for extracting Au in specialized clothing. hand skin and Airways must be protected from toxic fumes that may be harmful to human health.
You will also need a form, it must be made of cast iron. The metal is immersed in a flask or dish and heated with a burner. must take place in a special oven.
It is necessary to use dishes that are suitable for remelting gold, additional requirements are imposed on it. Since the metal is poured in a thin stream without interruption, the pouring vessel must have a spout, and the mold must be disassembled.
A home-made ingot is polished because its surface is not smooth. The ingot is ground using the following means:
- Pasta.
- Felt.
- Toothbrush.
Polishing will add shine to the ingot, for this reason it is better to use a specialized paste, it will remove roughness from the surface of the precious metal.
Metal is polished with felt after using the paste, if there is no felt, then cloth or suede can be used.
A toothbrush will be needed if not specialized tool for cleaning. Apply to the brush toothpaste and with its help polish the surface of the ingot. The procedure is also completed by polishing with felt or cloth until the metal begins to shine.
What can this gold be used for?
Au mined in this way is used with different purpose. Most often, gold is sent for remelting, making jewelry from the material. The quality of jewelry depends on the quality of the metal obtained. If the refining was not very successful, then the alloy will not differ in purity.
The ingot can be used as a material prepared for resoldering jewelry, that is, for repairing other jewelry. If a jeweler works with solder at home, then the resulting material will help to repair more than one product.
The resulting ingot can be handed over or sold. There is no particular difference. In the 1990s, many chemists made their living this way. They also dismantled old TVs and refrigerators by refining. In the technique of the times of the USSR, there was more precious metal, for this reason, refining was considered a very profitable occupation.
Extracting gold from radio components is not difficult, you just need to try, besides, the process is exciting. Many people do the procedure not for profit, but for the refining itself, which brings pleasure. But there are also those who want to hold a whole piece or ingot in their hands. precious metal.
Gold was one of the first metals that man began to use, and jewelry was made from it even at a time when stone and wood were the main materials. All this is due to one property - the element is often found in nature in practically pure form, nuggets.
For a long time, gold remained only a means of payment and a material for jewelry. Over time, metal has become indispensable in medicine, electrical engineering, weapons production and other sectors of the economy of all countries of the world. Despite the replacement of monetary standards, any country is trying to secure a certain gold reserve.
However, where did this chemical element(in the table of chemical elements of D. I. Mendeleev, gold is designated as Au (aurum) at number 79), how is it mined and used?
What gold looks like: chemical and physical properties
Gold nuggets
Gold is a noble metal, many have heard this name, but what does it mean?
Chemical properties. As a chemical element, it practically does not react, and is not affected by aggressive substances. In short, gold does not oxidize, making it an ideal material for many industries.
physical properties. What does gold look like? In its pure form, it is a rich yellow, rather soft metal, at the same time dense, which determines the considerable weight of the products.
If you take kilogram of gold and make a ball out of it, then it will be a sphere with a diameter of only 46.2 mm!
Pure material is very easy to process, easy to melt (melting point 1064°C), forged (very thin sheet can be made) and drawn.
Insignificant hardness is the main disadvantage, which is eliminated by adding impurities to the metal: silver, copper, platinum and steel. So there were different kinds gold.
Types of metal
banking gold
There are two main types of gold - banking and jewelry.
In the first variant, the purity of the metal is very important, where the main standard of 999 samples is adopted. This means that such a sample does not contain impurities of other elements. Such ingots are kept in state reserves and sold by banks as investments.
For jewelry gold, strength and durability are important. Therefore, pure gold is not used in jewelry because of its softness. Therefore, such varieties as yellow, white, red, pink, gray and even green gold appeared.
Additives and percentage of all elements in jewelry gold determine its price. The amount of gold indicates the sample, it shows how much precious metal is in the product. For example, the most common 585 sample means that the product contains 58.5% pure gold, and everything else is impurities.
The use of precious metal in various industries
Until the 20th century, yellow metal was exclusively a means of payment and decoration. And only with a jump in technological progress, it was increasingly used in industries. But even today, all significant volumes are concentrated as reserve stocks of means of payment of states.
10% of all available gold is in the form of industrial products. The main direction of production, where it is used, remains electrical engineering. Also, the element is indispensable in the production of neutron bombs, nuclear fusion, and in the space industry.
A very thin layer of precious metal can be used in windows to reflect infrared radiation for energy saving purposes.
Gold is indispensable in medicine, especially dentistry and pharmacology.
Popular mobile communication uses this element, each SIM card has a thin gold plating.
The main use of the precious metal- this is the gold reserve of the state, in all the gold and foreign exchange reserves of the world there are about 32,000 tons of precious metal.
The remaining volumes are personal investment funds of residents and jewelry.
The theories of the origin of the yellow metal are interesting. According to one hypothesis, the element was formed as a result of the destruction of neutron stars and subsequent accumulation on our planet. And according to another theory, gold was brought several billion years ago by asteroids. In any case, all the available reserves of the noble metal on Earth were formed a very long time ago - 3 - 3.5 billion years ago.
Even 100-150 years ago, in the absence of knowledge about the origin of the yellow metal, its mining was comparable to gambling. Today, having accurate understanding of the formation of gold in certain rocks, its mining has reached the industrial level with accurate data on how much of the precious element can be removed from each deposit.
In the entire history of gold mining in the world, about 160 thousand tons of yellow metal have been obtained. And the main part of this mass was extracted during the last 100 years.
Leading countries in gold mining
If relatively recently the South African region was considered the leader in gold mining, today other countries have taken the leading positions.
According to the latest data of 2016, the following top 5 leading countries in gold mining can be compiled.
Peru, South Africa, Mexico, Uzbekistan, Indonesia, Ghana, Brazil and New Guinea remain among the leaders in gold mining.
For the whole of 2016, 3,104 tons of precious metal were extracted, with each new year this figure is growing, although this is hampered by the gradual depletion of the mines.
The most famous gold deposits
The largest deposits and developments in gold mining are several mines: Muruntau (Uzbekistan), Grasberg (Indonesia), Goldstrike (USA), Cortes (USA), Pueblo Viejo (Dominican Republic). The volume of metal mined in these places ranges from 60 to 30 tons per year. There are also two largest first gold deposits, which are this moment not developed: Pebble Deposit in Alaska, USA and Natalka Kolyma - Russia.
Large deposits of precious metal in Russia, where development or preparation for gold mining is underway
Deposits are considered profitable for development, where the composition of gold in the rock is 2-5 grams per ton of rock. Today, these standards are constantly being revised. For example, the Natalka deposit is currently being prepared for development, and gold mining will begin in the near future.
All of the world's major mine development is owned by just a few companies that search for and mine gold around the world. There are leading companies in Russia (see).
The volume of gold mined depends on the types of deposits being developed.
Gold mining in Russia
In our country, the main areas for gold mining are concentrated in Transbaikalia and Siberia. There are also deposits in the Urals, but at the moment they are being depleted, since this region has historically become the first where the search and development of deposits began.
In the European part of the country, there are insignificant reserves of the precious metal in the territory Leningrad region. At the moment, the "Leningrad" deposits are considered unprofitable for commercial production. Although back in the 19th century there were imperial prospecting artels here. Now "black miners" are engaged in the search for gold in this region.
The bulk of the mined precious metal is extracted from ore mined at primary deposits. Placer gold mining in Russia has not lost its relevance, but the volumes are gradually declining due to the depletion of such deposits.
Gold mining
Where is gold mined and how are rich rocks found? Extraction of the noble metal occurs in two main types of deposits: primary and placer. What's the difference between them?
Where is gold found in nature?
Primary deposits are gold-bearing rocks that are extracted to the surface from quarries or mines. The most common is quarry mining. Such deposits should be sought in regions with a rich history of mountain building and volcanic activity, since it is the processes of melting and movement of rocks that form deposits of precious metals. The main volumes of gold mined today are obtained from primary deposits.
Alluvial deposits gold in nature today is very depleted. They are gold-bearing crushed rocks along the banks of rivers and streams. Formed as a result of the destruction and erosion of primary deposits, followed by the transfer and deposition of gold particles. A feature of such deposits is the presence of native metal.
Most big nugget in history was found in Australia in the second halfXIX century, the weight of pure gold in it was about 90 kg. The second largest weighed approximately 70 kg. The Russian record holder among nuggets had a mass 36 kg.
Today, gold mining is a rather lengthy and labor-intensive process that requires the processing of huge masses of rocks to obtain even small amount precious metal.
Extraction of floating gold from alluvial placers manually using a tray
On our planet, gold can be found everywhere, it is present even in the river and sea water. However, often the concentration is so negligible that the extraction of the element is simply not economically feasible.
Initially, the main method of extracting the precious metal was the development of placers. Extraction was carried out by a very primitive method, by washing the rock mass in a special tray by hand. Since gold is heavier than many rocks, it settled on the bowl. Since ancient times, mining has been carried out in mines. How is gold mined today, what technological processes used to extract it from the rock?
To this day, in the deserts of Egypt, ancient adits have been preserved, reaching depths of 100 meters where gold was mined 2000 years ago.
In the modern mining industry, all developments are mechanized and carried out with the involvement of specialized equipment.
The technological chain for the development of placers is as follows:
- diversion of the riverbed;
- overburden works (removal of the upper layer of rocks);
- extraction of gold-bearing rock;
- washing;
- cleaning;
- enrichment;
- remelting.
In cold regions, such mining is seasonal, and in winter, washing stops.
Mass production is carried out at the development of primary deposits open (career) or closed (mine) way(cm. .
The gold-bearing rock also goes through the stage of extraction to the surface, grinding, enrichment and separation of gold from impurities.
Gold casting process
The whole process of extracting gold is built on its physical and chemical properties. One of the oldest is the use of mercury. Precious metal particles were separated in this way back in the days ancient rome. The rock was mined and crushed, after which mercury was added to it. It formed an alloy (amalgam) with gold-bearing mud. Next, the mercury was distilled off, and the sludge was put into processing. This method of gold mining is possible only in very rich deposits, today it is practically not used.
Gold is separated by gravitational differentiation, when the mined rock is crushed with cast-iron balls in mills and sent to a centrifuge. Under the influence of centrifugal force, heavy particles of the precious metal are separated from the main rock.
There are other techniques based on the chemical properties of gold, such as cyanidation or leaching.
The noble metal is also searched for in the dumps of old mines. in an elementary way such surveys is the use of modern metal detectors.
Gradually known deposits depleted, and companies begin to develop those deposits that were previously recognized as unprofitable. This contributes to the development of gold mining and extraction technology.
In terms of gold mining, the Russian Federation ranks 4th in the world. Everyone at least once wore jewelry made of this precious metal or followed its bank rate. Let's figure out where they mine in Russia, who is engaged in this work in our country and how exactly the development of gold veins takes place.
Where is gold mined in Russia
Deposits of the yellow precious metal are located in the Urals, Altai and the Far East. Lead the booty large enterprises. Consider the main Russian mines.
- The Solovyovskoye deposit is the oldest in the Amur region and throughout the country. More than 150 years ago, the first handfuls of the precious metal were obtained here. Alluvial gold is located at a relatively shallow depth of 10 to 70 m. There are two methods of developing this mine: dredging and hydromechanized.
- The mine Udereisky is located in the Krasnoyarsk Territory. Gold is mined here in the same way as in the previous quarry. Forecasts promise metal volumes of 800 kg annually until 2025.
- The Nevyanovsk deposit was found in the Ural Mountains quite by accident in 1816. Walking along the local river, a little girl - the daughter of one of the residents - discovered a piece of a gold nugget. Hydraulic monitors are used to extract the resource.
- Gradsky mine is a gold deposit in the Chelyabinsk region. The precious metal lies too deep, so it is mined only by a closed method. But diamonds are also found here.
- Dambuki is a mine located in the Amur Region. For more than 100 years, gold has been mined here using the drag method.
- Konder is a precious metal deposit in the Khabarovsk Territory. A nugget weighing about 1 kg was once found here. Every day, 150 kg of gold is mined here.
- The Altai deposit has existed for more than 50 years. The ore contains 9 g of gold for every ton of raw material. In the next 30 years, you can not worry about the content of the resource in this place.
How gold is mined in Russia
Modern technology has greatly simplified gold mining. Previously, for this it was necessary to wash the sand manually with a sieve, but now most of the work for a person is performed by specially created mechanisms.
- Dredges are units installed on a moving platform. It is also the name of a vessel that is equipped with this mechanism for the development of gold deposits in riverbeds. The device processes surface sand around the clock in search of the precious metal.
- Washing plants complete the work of the dredge, separating gold from excess impurities. The hydromechanized method in combination with the drag method is used in many mines.
- Hydro monitors are another device for the development of gold deposits. A dense jet of water destroys rock, allowing you to get to the deposits of the precious metal.
Private mining is prohibited in Russia, and lawbreakers who succumb to the gold rush face a considerable prison sentence. Despite this, in those places where deposits are discovered. Even for found hidden gold dust, you can get punished when trying to store or sell.
Only specialized enterprises legally mine the precious metal in Russia. The received resource is carefully registered and surrendered to the state. Gold is processed into bars or coins. Only then does it enter the market.
- In 2015, 234.24 tons of ingots were produced in Russia from the metal obtained in this way.
- Associated gold came out 16.97 tons. This is a resource obtained not at specialized mines, but in places where other minerals are mined.
- Secondary gold produced - 38.26 tons. It was created from metal waste or scrap.
Russia is a rich gold-bearing country. Huge reserves of the resource will last for several decades. There is the most placer gold on the territory of the Federation - in its development, the state ranks first in the world.
- About 20% of all production is accounted for by PJSC Polyus Gold, founded in 2006. The forces of this organization extract precious metal in Irkutsk, Magadan, Amur regions and in the Krasnoyarsk Territory.
- PJSC "Zoloto Kamchatki" is a leader in the development of the resource in the territory of the Kamchatka Territory. It was created as a result of the transformation of Koryakgeoldobycha. To date, the company has big plans for the extraction and processing of precious metals.
- PJSC "Susumanzoloto" was formed on the basis of an enterprise for the development of a gold mine that existed in the Magadan region since 1938. It happened in 1994, and since then there have been many subsidiaries involved in various fields resource processing and extraction.
Gold recovery technology is based on several procedures that have long been used by many people. You can also get gold yourself at home. Let's take everything in order.
You can extract gold from new or used radio parts. Surely you have electrical circuits, diodes, contacts, transistors, clock cases, relays and other similar items at home. Uninitiated people consider it garbage, and experts in the extraction of precious metals specifically purchase these parts for ridiculous money. Soviet-made equipment can contain up to 10% of gold. Previously, it was often used in the manufacture of such products. To understand how much gold is in the products, read the technical documents. This information will be useful to you in order to calculate the required amount of solutions. Unfortunately, information about the content of metals is not always valid. But the documents of domestic technology contain only reliable information, so you can safely trust them. Disassemble the parts to the minimum parts to leave the product element with maximum concentration gold. You should get portions of 1-3 g. Before work, ventilate the room well. Be sure to use a mask, gown, goggles and gloves. To get gold, prepare "royal vodka". This solution is a mixture of nitric and hydrochloric acid in a ratio of 3:1. Make a mixture and heat it up to 70-80 degrees. After that, take one workpiece with a gold content and place it in the prepared mixture. Technical details contain a lot of copper, so most likely the mixture will turn into green color with a dark tint. You need to evaporate it until the volume of water is reduced by 2 times. Also in the products is iron, which forms a brown precipitate. To dissolve it, pour 2 ml of hydrochloric acid into the mixture.
As you can see, to extract gold, it is not necessary to have deep knowledge in the field of chemistry. Just follow the above steps in order and follow the safety precautions. Take the last point seriously, since harm can be obtained even by inhaling acid fumes.
During its existence, humanity has mined and processed more than one hundred thousand tons of gold. About half of this reserve is used in jewelry, one third is stored in state banks and one-fourth is employed in industrial enterprises. Gold mining by amateurs in the artisanal way has been going on for a very long time.
All the gold mined in the history of mankind will be a cube with an edge of 21 meters.
Several methods for extracting the yellow metal
The main share of gold is mined using two methods - sand washing with a jet of water and mining in mines.
Artisanal gold mining is carried out in those places where industrial methods have already been developed, and when the latter have become unprofitable, artisanal mining can give good results on the remnants of the former "luxury". Basically, gold is mined by people from developing countries, financial position which pushes citizens in search of alternative income. In Africa, Asia, South America, more than 10 million people are engaged in gold mining in free time. They take risks to help their families make ends meet. This method of gold mining is easily accessible to uninitiated people. To imagine how gold is mined independently in an artisanal way, you can watch thematic videos shot by numerous yellow metal hunters.
Artisanal gold mining in Africa provides income for millions of people.
Enough importance for gold mining are gold deposits formed due to volcanic activity. Such deposits lie close to the earth's surface. Among them are Khakanja in the Far East, Kuranakhanskoye in Aldan and many others. Gold is also mined from pyrite-polymetallic deposits of Rudny Altai, igneous copper-nickel deposits located in the north of the Krasnoyarsk region, and gold-bearing skarns, which are located in Olkhovka and Chibizhka at the junction of the Minusinsk Basin and the Eastern Sayan.
In many respects, primary deposits are inferior to placer deposits. The MAIN advantage of alluvial deposits is that their development requires much less funds.
These deposits are conducive to the fact that they would be mining gold "the old fashioned way" - manually. That is why, in Soviet years the state was actively developing alluvial deposits, putting aside primary ones “to the far shelf”. The decrease in the intensity of alluvial gold mining, which occurs in last years, is capable of increasing unemployment in Siberia and the Far East, which may provoke an outflow of the population from these parts of the country.
The technology of washing gold particles in a tray has been known for a long time.
Mining of gold by miners is carried out by centuries-old technology of washing particles of precious metal in a tray. This technology has come to today from ancient times, when washing was done using sheep skins. It happens that rains can wash gold into the river. Prospectors hunt for such "consequences" of the elements.
One of the most debilitating and difficult methods is to dig out (presumably) gold-bearing rock with a shovel. Since in this case the desired gold is mined only by hand, the whole work is as follows: a small amount of rock is dug up, then washed in a small tray. Heavy, unwanted metals are crushed to sand, then washed again. Then the most exhausting - the careful selection of gold particles, which takes place manually.
Facts about artisanal mining in Russia and other countries
In many countries, including Russia, artisanal mining is illegal gold mining. In the Russian Federation, gold mining is prohibited in the absence of an agreement with gold mining companies that have a license to conduct gold mining operations. The latter is very expensive.
In contrast to Russia, in Australia and America, a license to mine the precious metal costs mere pennies - $30. Gold mining tourism is very developed, therefore all citizens have the opportunity, without fear of punishment, to arm themselves with a metal detector and look for their small "increase in salary". Small-scale gold miners contribute about a ton per year to the world's gold production. Such a mass, although impressive, does not affect the price of the precious metal in any way.
In Australia and America, having bought an inexpensive license, anyone can become a prospector.
Artisanal gold mining was carried out by the ancient Greeks, who mined it by washing gold-bearing sand on sheep skins. The essence of the method is that the denser types of metals settle on the grate, while the less dense ones leave it. Since gold is one of the densest materials, it is mostly held up in the lattice.
Mining gold mining is extremely difficult and inefficient way. the ancient Greeks had no choice, just like today's developing country miners.
But there are also positive aspects: this technology does not provide for the construction of factories chemical industry, expensive equipment, high production costs for rock crushing. Washing of the rock is not used in scattered gold deposits, where the size of the precious metal particles does not reach one millimeter and in deposits where the rock does not separate from gold after crushing.
By the end of the nineteenth century, virtually all gold was mined using the extraction method from gold ores. This method was chosen because of the depletion of river deposits, in which there was less and less gold.
Now there is a mining of ore gold, which is mined from the bowels of the earth's crust and chemically separated from various foreign impurities.
Non-industrial methods for extracting precious metal from ore
There are several ways to extract gold without the involvement of industrial equipment:
- Mercury amalgamation;
- cyanidation and flotation;
- Chlorination.
The first method involves amalgation of sand with a fraction of gold not exceeding one millimeter in size. The technology is quite simple: the metal is dissolved in mercury to obtain an amalgam. Then it is separated from the rock by filtering through a fine-meshed tissue. In the resulting alloy, gold makes up about half of the total mass. To separate it, mercury is evaporated.
Mercury amalgamation was known and widely used in the Middle Ages.
The second method includes leaching, concentration and a purification step. The precious metal is leached due to the interaction of cyanide with oxygen, then the concentrate is removed using Activated carbon, filtration and calcination.
Cyanidation produces a purer metal than amalgation..
The disadvantage of this method is the high danger of cyanide fumes. Cyanidation is essentially a hydrometallurgical process. During the first years of use this method only potassium cyanide was used, later, calcium cyanide became widespread. With the development of this type of gold mining, it turned out that fine grinding gives top scores than previously used, coarse grinding of ores. For grinding various ores, tube and ball mills are used, which operate on closed classifiers. Now combined air-mechanical agitators are used.
The third method involves the use of hydrochloric acid and chlorine, which can dissolve gold. After that, the gold is sifted from the harder inclusions and melted into an ingot.
Is it possible to mine gold in Russia?
We must not forget that illegal gold mining in Russia is considered a criminal offense and is punishable by restriction of freedom for several years. This is spelled out in Article 191 of the Criminal Code. Russian Federation. You can increase the punishment to seven years by mining gold in groups.
Many scientists are convinced that the practice of the United States and Canada, where a gold mining license is easily bought for a small amount, would be appropriate in Russia. The connection of companies and small gold miners can significantly increase the extraction of the precious metal.
The consequences of the ban on independent mining gold has become that one tenth of the gold production is illegal, that is, bypassing the state treasury.
Fundamentals of Artisanal Gold Mining
Artisanal gold mining is based on the following principles.
The water flow supports lighter particles in weight, and acts on heavier ones in inverse proportion to their weight, depositing them on the bottom.
The translational movement of the masses that are on the surface, which is under an inclination and which is affected by the flow of water, depends entirely on the speed of the water, which is less at the bottom than at the surface. Because of this, when flushing occurs, larger diameter grains are most affected, while smaller grains remain motionless on the bottom.
During the precipitation of a mixture that is in a loosened state in the form of a semi-liquid mass, smaller grains pass into the gaps between the large ones.
The further fate of gold mining
Many scientists are struggling to find a new source for the precious metal, because, according to some estimates, gold reserves will run out in half a century. One of the most promising methods is gold leaching.
An advanced method of mining from the bottom of the Bering Sea.
Except chemical methods, discover new deposits can help development water element- the ocean. Quite often, sea placers of gold are found, not to mention the ocean floor, about which little is known at all. It is likely that there, under water, are the richest reserves of the precious metal.
