The process of gold mining today is practically no different from the first methods of searching for the precious metal. As before, ingots are searched for in mines or along river banks. But modern technology has made the process itself much simpler and easier.

There is no longer a need for mine managers to hire large numbers of people to work. Several people can handle the task with the help of special equipment.

A dredge is a machine for washing gold. The complex structure of the unit consists of several components, each of which performs specific functions:

• Digging and scooping the earth. A powerful bucket can daily handle at least a ton of earth per day. This replaces 12,000 workers, which significantly saves not only human resources, but also time.
• The land is enriched in the process of work. This is of great importance from an environmental point of view.
• The machine independently selects pieces of gold from the soil, and after processing the soil itself is sent to its original place. There is no longer any need to manually filter or control this stage.

Due to its heavy weight and high cost, only large entrepreneurs can purchase a dredge.

Before purchasing, it is very important to analyze the amount of precious metal in the places for which the dredge is purchased. Since there may be relatively little gold in the soil, purchasing a dredge will simply be unprofitable.

The area where the dredge will operate must have soil with high humidity. Therefore, the optimal areas for installing the unit are coastal areas of rivers or lakes.

Installing a dredge is a very labor-intensive process due to the heavy weight of the machine. As a rule, two types of products are most widely used:

1. which moves through the water along the shore. In appearance it resembles a swimming vessel.
2. Continental Dredge. Its purchase and installation are very expensive, since the basis for such a machine is a pontoon.

The operating principle of a dredge for gold mining technology is similar to a vacuum cleaner: the sucked soil is processed, filtered and enriched. Thanks to high-quality filters, the dredge can retain even the smallest gold particles.

The dredge is filled with diesel fuel. Certain types of machines run on electricity or steam. The scoop reaches a depth of 50 meters, which makes it possible to thoroughly examine the soil for the presence of precious metal.

The main advantage of the dredge is that it greatly simplifies production. After all, one machine can replace hundreds and even thousands of people.

It was in this regard that prospectors were puzzled by a new pressing question: how to make mini-dredges for gold mining with their own hands.

It is important to remember that gold should be mined only on the basis of the appropriate permit and a special license to carry out such work. Otherwise, the violator faces not only administrative, but also criminal liability.

A self-made machine for searching and mining gold is a simplified technology and is called a mini dredge. Its design is simple, and the main materials are plastic or aluminum.

To improve the buoyancy of the dredge, car tires are attached to it. An analogue could be plastic barrels. In addition, the components of the device include:

Checking a homemade machine is carried out using labeled lead. If it is returned to the owner in full, then the machine can be used for gold mining.

It is very important to understand that you can only use your unit in a legal way. Everything must be legislated.

The desire to get easy money has never gone unpunished. Due to the proven effectiveness of mini-drags, more and more people are trying to make such a machine themselves.

Gold has been mined since ancient times. For the entire period while this activity is carried out in the world, the scale of production of this noble metal is approximately 170 tons. Half of the gold mined goes into the production of jewelry, which is quite expensive. According to scientists’ calculations, if all the mined gold is collected in one place, then it is possible to form a solid cube the height of a 9-story building with a 20-meter edge.

World gold mining

Nowadays, gold mining is not an exciting adventure that ruins some people and makes others rich. Now, this activity has become an actively developing type of income.

Enterprises that are engaged in industrial gold mining maintain accounting records, calculate economic feasibility, and conduct geological exploration using modern technologies. That is, it provides a workplace for many people with different professions.

Dozens of countries account for global gold mining, and the Russian Federation is no exception. Gold nuggets here are rarely found on the surface of the earth, however, at some depth underground, there are so many gold deposits that it allowed the Russian Federation to take fourth place in the production of this noble metal in the world. Today, Russia holds 7% of the world's total gold reserves.

The absolute leader in gold mining since the early eighties has been the Republic of South Africa, which provides about 70% of all gold production. Although, in the early nineties, South Africa's income fell by 35% due to a decrease in exploration of new gold deposits. And some states, such as Australia, on the contrary, have begun to increasingly develop underground and surface gold deposits located on its territory.

Methods of gold mining in Russia

Over time, gold mining methods have constantly improved and changed. At first, manual gold mining was widely used by sifting sand in water.

Then people mastered the extraction of noble metal from ore. These days, manual gold mining is a rarity. This process is mostly automated, but that doesn’t make it any easier. After all, to find a profitable deposit you need to spend a lot of effort and money. A payable deposit is considered to be one in which there are 3 grams of pure gold per 1 ton of soil.

More recently, a method called amalgamation has been popular in the gold mining industry. Its peculiarity lies in the use of a container placed at the bottom of the container. The barrel was filled with gold-bearing ore and shaken. As a result, gold particles remained in the mercury at the bottom of the barrel. The main negative quality of this method is the high toxicity of mercury.

Nowadays, gold is separated from ore using sodium cyanide. Thanks to the advent of this method, it became possible to extract gold from previously abandoned deposits, which returns their profitability.

Gold is also mined using dredges - surface-mounted mining machines equipped with everything necessary to extract metal from the ground. Dredging only works in areas with certain soil. This must be a watery area, so such special vehicles are often installed near river banks or other bodies of water.

What is a dredge?

A dredge is a device that is directly related to gold mining. The weight of this device reaches several hundred tons. This is a mechanized unit equipped with buckets operating on the principle of a chain excavator. On board the floating platform there is everything you need to wash rock and sand. A large dredge can be controlled by a crew of up to 10 people, while a small special vehicle requires only one manager.

The cost of dredging for gold mining is available only to large enterprises. Before installing this machine, you need to remember that this idea may be unprofitable if the content of precious metals in the soil is low.

Therefore, before using this special vehicle, it is necessary to carry out a number of reconnaissance activities, including geological research and chemical analysis of the soil composition to determine the concentration of noble metal in it. Only in this case will the profitability of industrial gold mining be justified. In addition, installing a dredge requires a lot of effort and time, since the machine is quite heavy and bulky.

Classification of dredges

Dredges are grouped:

• by the type of energy required for the operation of the device: electricity, energy from the combustion of gasoline or diesel fuel vapors;
• by depth of work with rocks below the water level: shallow-water, deep-water;
• by bucket capacity: small, medium, large;
• by maneuvering method: rope-pile, rope-anchor.

As a rule, two types of special machines are used for gold mining:

• marine;
• continental.

These types of dredges differ in that the marine special vehicle is similar to a ship that can be moved along the coast, while the continental one requires more resources, as it is mounted on a pontoon.

Smaller special vehicles called mini-dredges are ideal for individual gold miners or prospectors. They can either be purchased in special stores or made independently. The mini-drag has been significantly reduced in size. Its weight ranges from 25 to 100 kg.

A positive feature of using mini-dredges is that they reduce labor costs and speed up the gold mining process. Therefore, the interest of miners in constructing the unit with their own hands at home is justified.

Operating principle of the dredge

Externally, the mini-dredge looks like a vacuum cleaner that sucks up sand and gold dust in order to separate one from the other. All possible models of these special vehicles differ in size and materials from which they are assembled, but their structural elements are similar:

• a system that provides buoyancy of the device;
• drive responsible for the operation of the centrifugal pump;
• injector;
• washing chute for separating precious metal from slag;
• air supply system for breathing underwater.

Metal extraction using a mini-dredge is divided into 3 stages:

• pumping water under high pressure into the injector chamber;
• then water with sand and earth is sent to the washing trench to separate the noble metal from the slag;
• the drive starts the pump to sift out the gold in the trough.

The performance indicator for all devices is different, but on average it ranges from 100 to 1000 kilograms of processed rock per hour. Before you start working with a mini-dredge, you need to clear the bottom of the reservoir from stones, because they can clog the unit.

A miniature gold dredge is an effective and popular unit for gold mining. It is modernized over time and becomes more and more popular in prospecting circles. First, you need to seriously invest in the purchase or assembly of the device, but then this investment will bring considerable profit.

Before assembling homemade mini-dredges, you need to know that gold mining is prohibited in the Russian Federation. Along with this, artisanal mining of this precious metal is close to crime.

Video: Gold mining on a dredge

Of course, many prospectors would like to have such a wonderful gold mining device as their own suction dredge, but the prices for this equipment, unfortunately, are high. However, we should not forget that at the dawn of dredging, there were no factories producing dredges, and these small devices were assembled by hand in some garage. So if you make it yourself, you will save a lot of money, just like I did.

Of course, you will use everything that is cheapest, but do not count too much on the fact that you will get by with a symbolic amount. No one wants everything on their drag to be wobbly, falling apart, or not working. The device must be functional, reliable and durable. You will not waste your time thinking about your project and deciding what to do and how to do it. Think about what exactly you want to get in the end and what you need, weigh everything together and decide what you can afford. Make diagrams and lists. Perhaps the best thing I can advise you in this case is to study the design of devices from such well-known brands as Keene and Pro-line. These companies have done extensive research on their equipment, tested various settings, and improved the components of their dredges so that they perform excellently. By visiting the websites of the above-mentioned companies, you will find excellent photos of these devices and view information about the components from which they are made. If your local prospecting store sells ready-made dredges, examine them carefully, perhaps even take some measurements and, if possible, take photographs. Another great opportunity is to join a prospecting club whose members are active in dredging. It won't hurt you if you watch them at work. Members of such a club may even allow you to stand behind the dredge yourself. The more general knowledge you have about dredging, the better your design will be.

If you find a landfill or recycling plant, then you can get some important parts at the lowest prices. I advise you to take a list of the necessary components and materials and visit such a place with it. There you can even find the right engine for your dredge.

When you finally get around to building your own dredge, the first question that will probably arise is how big you want to build it. The larger the dredge, the more soil it can process, but the greater its weight and cost. You must find a compromise between these values, focusing on the volume of material being processed and the possible depth at which you will dredge.

Another aspect that is worth thinking about is that you are better off building a dredge with a hose diameter of 10 - 12 centimeters, that is, it should be of such a size that you alone can handle it. Although, if you are a young, tall strongman, you may be able to carry a 14-centimeter device, but this will take a lot of effort and time. 10 centimeters is perhaps the best size for equipment operated by one person.

Do you need compressed air for diving? Then you will need an air compressor, an air intake tank, and also diving equipment. Air is a really handy thing, but it's not at all necessary: ​​you can always do it later if your project is good and you're planning on installing a compressor on your dredge.

To build your dredge you will need a motor and a pump, as well as various tools, such as a hacksaw, riveting hammer, screwdrivers, wrenches, etc. The more experience you have in this type of work, the better your dredge will turn out. Knowing how to use a welder is also very important, as my little 120 volt welder has helped me solve some pretty tricky problems during the build process. If you don’t have such a device, then this is another reason to buy it! I highly recommend you have a welding machine.

Pay close attention to the price of the parts and decide what you can afford: you, of course, can save a lot of money by assembling the dredge yourself, but you will still have to spend money. I strongly recommend that you calculate the expected costs before you start purchasing the necessary components. Make sure you have enough money for everything. As for me, I decided to purchase some parts from Keene because I don't think I can make them any better than that company. On the other hand, I also bought some used components.

Everything I used to build my 10cm dredge cost about a third of what it would cost to buy a new one.

Here are my comments on what you can do yourself and what you need to buy:

Almost impossible to do yourself (but you can buy used)

Engine

I've seen really good homemade dredges, but no one has installed homemade engines on them as well. You can buy a used motor and save some money, but no one makes this part themselves. Make sure your engine has the correct holes to attach the pump to it. Select its size according to the pump size. Manufacturers use specific dimensions for these components, as well as the dimensions of the hose used. Focus on them.

Water pump

Like I said, I've seen some really great homemade suction dredges, but again, no one has installed homemade pumps on them. The centrifugal pump used by all dredge manufacturers is the best choice. I recommend that you purchase a pump from Keene. I bought mine used at a local goldsmith's shop. Do not use a slurry pump: the large volume of sand and gravel that will flow through it will quickly damage this part. They are also quite heavy and will require a larger motor.

Air compressor

I have a compressed air pump but haven't installed it on my dredge. I have been dredging for many years, but have never used anything other than a snorkel, although of course this imposes its limitations on the choice of bodies of water for work. In this case, if you have long arms, you are truly lucky. If you do have a compressor, make sure it can be connected to the motor. Do not use pumps or hoses that are not designed to produce breathing air.

Hose

There are many options when choosing a hose, but be careful: the thin and fragile materials from which this part may be made will wear out quickly. The transparency of the hose is also important - you can see where it is clogged. The materials used by dredge manufacturers are excellent: they are reliable and will allow you to successfully dredge.

Ore washing chute (sluice)

The gateway is perhaps the biggest and most important thing you can do on your own. This is the key and most important detail - if your gateway doesn't capture the gold, the whole project will go down the drain.

I have used a homemade 4-inch dredge for many years in various California fields. In order for the device to suck in more rock, some time ago I replaced the old pump with a new, more powerful one. However, as I continued my work, I noticed a decrease in the share of fine gold being mined. I knew that old-fashioned sluices were not very good at catching small metal particles, and increasing the amount of material fed further reduced the recovery rate.

One day in 2002, while working on a dredge, I noticed a small nugget move too far down the sluice, almost falling out of it. Its weight was 8 grains. Thus, I realized that I needed to do something to prevent gold from being lost in the process. I began to think about this problem. Driven mainly by high prices, I decided to build my own gateway. I didn't have a specific plan or plan, but being a mining engineer by training, I have access to the equipment needed in this case, so my project did not seem impossible. If the New 49ers make their own gateways, why can't I? In addition, I had a certain amount of money.

The design of almost all portable gateways is based on the so-called “Hungarian” stencil, which I wanted to install for myself. The idea of ​​the “Hungarian” (also called LazyL) stencil is as follows: water and rock flow through the stencil, and behind each threshold a small waterfall is formed. Light particles pass on, and heavy particles, such as gold, are deposited. There is nothing technically complicated here: the thresholds are made from a piece of steel. All this can be done independently. These steel thresholds are much more effective than any other. When considering my own gateway, I carefully examined similar equipment in the nearest prospecting store, and also visited the GPAA Gold Prospectors exhibition, where I paid special attention to Keene gateways.

I decided that a gateway equipped with such a stencil is the best choice for me and with the help of such a device I will extract all the small gold that is possible. Keene uses this design on its latest drag models. But first, I had to get a bell (a device for feeding rock to the sluice). However, it is very difficult to make, so I purchased a bell from Keene. They are made of molded plastic, and this is the main reason to buy and not make it yourself. When I purchased the bell for my project, I expected the piece to fit a 16-inch (40 cm) wide sluice. My old sluice was 53 inches (132 cm) long, and the new one had to fit the existing frame (I didn't want to remake it). I spent a couple of days scouring the surrounding landfills, looking for anything useful. My entire project was based partly on what I already knew about the operation of similar equipment, partly on what I saw in commercial samples, and partly on what I was able to find in junkyards or what I had lying around in my garage.

The more time you spend thinking about the design of your future DIY gateway, the better. Of course, you don’t really want to buy any unnecessary parts, but at the same time, the device must be effective. A good work plan and understanding of the gold mining process itself are very important. Prospector's moss, which is not used on commercial equipment, is, in my opinion, a very important detail in the design of the gateway. I laid it under all the thresholds of my device. In a three-section airlock, most of the gold collects in the upper part. When the pebbles pass further, they are caught on a screen with 5mm holes (on my sluice). Then, the remaining pebbles and tiny gold pass to the bottom of the sluice. There, the slower speed of the water allows small metal particles to settle. Material larger than the holes on the screen goes into an additional section of sills before finally exiting the sluice. This is a common device of similar equipment

I borrowed metal shears and a press brake from a friend of mine. I cut the steel into strips and bent them into sills. They looked like standard Keene gateway parts, modified in the Hungarian way. To make the sills, I secured the edge of a strip of steel about a quarter inch and bent the rest at a 45 degree angle. If you have a press brake, then doing all this is not a problem at all. The thresholds of the upper section are 18 mm high, the next one is 30 mm high, and the lower one is 9 mm high. I used standard 1.5mm mild steel for all sections. The airlock itself is a large piece of bent aluminum. You can do it in two hours.

A project like mine requires special tools such as tin snips, a press brake, and welding equipment. It is impossible to do without it. Once you have cut and bent the steel the way you want it, the next step is to weld everything. In order to mount the thresholds, welding will also be required. There's nothing complicated about it. I'm not the best welder, however, and I managed to make everything strong and secure.

In order to secure flat strips of steel in the right place, they are welded at the ends of the thresholds. The straight part of the threshold is welded at a right angle to the bottom of the gateway, and the bent part at an angle of 45 degrees. Figure 1 shows a set of welded and painted thresholds ready to be installed on the airlock.

Fig.1

Completion of the project

For people with the right tools and some metalworking skills, making a gateway like this is not the most difficult thing. I spent about 10 hours on all this. The gateway took much longer to plan and design.

Modification of floating frame

In order to use the frame I already had, I had to make some modifications to it, namely raising the engine a couple of inches and accommodating a bell that runs underneath. I have truck tire tubes on my frame.

The frame itself is quite wide, but there is no difficulty in trimming it if necessary.

Exploitation

When I first started, I noticed a big difference between the performance of my new gateway and the old one. The light water no longer foamed on it, but flowed very well and correctly. When I first scraped, I found that fine gold was much better recovered. In general, the gateway did what was required of it. I've never had problems with sections overloading, although it does happen to those using Keene equipment. I lengthened the section where the 3/8″ sills were installed a bit and noticed that the slope was not enough and the water was carrying up large particles of pebbles. After I removed this part, it seemed to me that the device still worked great, although perhaps the removal would have been increased with the missing section. Next year I'll shorten it a bit and try again.

Work report

When I cleaned the lower sections of the sills, I noticed that along with the "black" sand, there was only fine gold left there. According to Keene's advertising, their equipment deposits 90 percent of the visible gold in the first section, which means my gateway performs about the same. A small amount of gold was found behind the thresholds of the upper section, so I placed prospector's moss there. The first cleaning showed a significant increase in gold recovery. Even more than I expected.

In my opinion, the main thing to do to improve extraction is to get rid of the junction box. The bell slows down the flow and distributes the material, thereby increasing production volume. Just compare the fact that all the light water is bubbling and foaming in the box of my old sluice with the work of the new version of this equipment.

The design of the gateway held up well, only once during the work process did a piece of welding break, which, however, did not affect the functioning in any way.

For those who are interested in making their own gateway, I can say that with metal working skills, it is quite easy to do. If you are making a gateway, into which the material must be fed with a shovel, then, in this case, the design of the device will be even simpler.

Building a homemade gold mining sluice, in my opinion, is a great start for a beginner. You just need to carefully study commercial copies, and then develop your own project.

On the other hand, if you are making a sluice for a dredge, I recommend making it two levels. These install Keene and Proline on the latest models of their drags. I don't have ready-made drawings, but you can draw them yourself, it's not difficult, just look at your friend's gateway or the one they sell at your local prospecting store. Be sure to use prospector moss, placing it under the thresholds. This detail will significantly increase the ability to “catch” gold.

Here is an estimate of my costs for creating a gateway:

Aluminum pieces $10

Iron pieces $5

Paint $4

Prospector's moss $56

Welding Rods $8

I think a new dredge sluice of the same size would cost over $500. The funny thing is that I spent the most money on prospector's moss. I actually think it improves gold recovery. This is perhaps the second most important detail after the bell and increases the production of fine gold.

The remaining elements of the dredge are described below.

Bell (water catcher, junction box)

It is installed in the head of the gateway and serves to direct the flow of water and soil into it. Here you need to make a decision. You can make it quite easily. Personally, I splurged and bought this part from the same Keene company.

Suction valve for drawing water into the pump

The suction valve is a very important part that is sometimes underestimated. You can assemble it from a piece of pipe and a sieve, welding it all with a short seam. Suction of sand can very quickly render your pump unusable, so don’t even try to dredge without a suction valve - all manufacturers complete their equipment with them.

Suction device (hydraulic elevator)

It is quite difficult to make, but if you have welding skills, it is possible. First you need to determine whether you will use it on your dredge suction tip nozzle ( suction nozzle) or suction nozzle .

Suctiontip(nozzle) has been used since the advent of the first jet dredges. Its essence lies in the fact that the suction device (hydraulic elevator) is placed at the end of the supply hose (Fig. 2). In this case, a stream of water from the pump is supplied to its beginning through a nozzle and a vacuum is created here. The main inconvenience of this scheme is the need to have two long hoses, one from the pump to the nozzle, and the other for feeding the rock. It is difficult to control a suction nozzle with two hoses attached to it, especially on large dredges. Therefore, the tip is used only on small dredges when working in shallow water. The suction tip works more reliably in shallow water than the nozzle.

Fig.2 Suction nozzle

Suction nozzle differs in that the device that creates the vacuum is adjacent directly to the receiving box of the flushing sluice. In addition to more convenient control of the suction hose when extracting soil, this design has a number of other advantages. Considering the proximity of the power unit (engine and pump) to the nozzle, it becomes possible to install two, three or more pumps with separate pipes, which significantly increases the performance of the dredge with the same diameter of the suction hose. In addition, the short length of the hose from the pump to the nozzle leads to significant pressure stabilization, and, consequently, to greater stability of the entire system as a whole. At the same time, when working in shallow water, air may enter the suction hose, and the rock supply will stop until the hose is completely filled with water. Therefore, in shallow water the nozzle is less effective and a suction nozzle is preferred.

Providing buoyancy

At this stage of creating a dredge you can save a lot. You can ensure the buoyancy of your device in a variety of ways. At the very beginning of the history of the use of dredges, large tires from trucks, which weigh little and are inexpensive, were used for this purpose. This is the option I chose for my own model, but I quickly discovered that getting such tires is becoming more and more difficult.

Today, manufacturers install plastic pontoons on most dredges. They are more reliable, but at the same time, heavier. There are many options here too. On some home-assembled dredges I have seen a variety of types of these plastic pontoons. An interesting way is to use plastic containers or barrels (20 - 40 liter capacity). They can be bought quite cheaply. You can, of course, purchase pontoons from a specialized drag manufacturer, but this will cost a pretty penny.

Another important part of the buoyancy system is the frame on which the ore chute and motor are mounted. I made it from pieces of aluminum found in a landfill. All this was very cheap and did not require much effort. Since the frame was flat, I easily attached truck tires to it.

Checking dredge operation

Once you have found all the necessary parts and assembled the dredge, it is time to check how it works. To do this, take a couple dozen small pieces of lead, line them up and paint them with a bright paint, such as red. Take some soil from the nearest body of water and place the lead there. Test your dredge on this soil by washing the rock, removing the concentrate from the sluice and counting how many pieces of metal you extracted. Losses should be no more than 1-2 pieces. If, unfortunately, it happens that more lead is missing from the gutter than is written above, you need to adjust the dredge, make the necessary improvements until you are sure of its good work.

Finally, you will need a specific type of diving suit depending on where you will be using the dredge. Even in California in the middle of summer, after two hours of being in the water, it gets damn cold, so this kind of protection is a must.

Today, little has changed in comparison with the last century - the essence of the process remains the same. Gold is still mined either from mines or from placers on river banks. But with the advent of technology, the process has become somewhat simpler. And now several thousand workers can be replaced by a dredge for gold mining.

Special machine for gold mining

The machine is a huge mechanism that includes several structures responsible for:

• Scooping the earth. The dredge bucket has the ability to lift more than a ton of earth to the surface per day. This is equal to the human power of 12 thousand workers. The productivity of gold mining in this way increases a hundred times.
• Enrichment of the land, which is also important when mining gold.
• Filtration and processing of the resulting soil. The dredge itself filters out the gold particles, and the processed earth comes out unchanged. Workers do not even need to monitor the filtration process and do it manually, as before.

Industrial dredge

A dredge is a device that fully embraces and speeds up the process of extracting precious metals. Of course, such a machine weighs more than a ton and is expensive. Therefore, only large enterprises can afford its purchase.

Before installing a dredge, you should remember that this undertaking may be unprofitable if the soil has a low amount of the noble element. Therefore, before using a special machine, a series of geological and chemical studies should be carried out on the composition of the soil and the concentration of gold in it. Only then will the cost of the mined metal exceed the cost of installing the equipment. The machine only works in areas with a certain type of soil. The area must contain a large amount of water, so special vehicles are often installed near the banks of rivers or other bodies of water.

Installing the dredge will take a lot of time, since the machine is heavy. There are two types of special vehicles most often used:

• Sea dredge. It is a floating vessel-like structure that can be moved along the coastal zone.
• Continental dredge, which requires more resources because it is installed on a pontoon.

At one time, the dredge can extract from one hundred to three hundred liters of water, which greatly simplifies production. The machine works on the principle of a vacuum cleaner, while filtration and enrichment processes take place, so even the smallest particles of gold are retained in the device. The dredge uses either electricity or diesel as fuel. Sometimes options for working with a couple are possible. The depth of the scoop reaches a maximum of fifty meters.

The main advantage of using a machine is to simplify the work of people. This machine also speeds up the mining process and makes it productive.

Therefore, many prospectors became interested in how to make a device at home. But before you start the process, you should remember that independent gold mining without a license is prohibited in the Russian Federation. Violation of this article results in criminal liability. Gold mined in this way can only be sold on the black market, where its value will be reduced. In addition, the sphere is closely connected with crime.

Parts for making dredges

A self-made dredge may be of interest not only to prospectors, but also to engineers. The mini-dredge for gold mining has a fairly simple design. The main material for creating a machine is either aluminum or plastic. Moreover, car tires or plastic barrels must be attached to the frame of the device for buoyancy. The device also includes:

• Engine.
• Water pump.
• Compressor.
• Hoses, their ideal diameter is 10-12 centimeters, which regulate the load.
• A trench for washing the soil, you need to make it yourself. The inside of such a trench is covered with special diligent moss, in which grains of gold are retained. It is made of steel and also has an aluminum gateway attached to it.

Don't forget about the valve, without which the dredge will break. It protects the pump from sand from the wash water. You can check the dredge using marked lead, which is thrown into a regular body of water. If, as a result, almost all the lead is returned to the owner of the mini-dredge, it means that the device is working.

Using a mini dredge can be dangerous and illegal. But many risk their reputation and lives in the hope of finding gold and getting rich. The effectiveness of using even a smaller copy of a special machine has been proven and therefore more and more craftsmen are trying to design this device.

The history of gold mining goes back centuries; since the development of the deposits, humanity has processed more than 100 thousand tons of metal, half is spent on jewelry, one third is stored in banks as gold collateral, the rest went to production needs.

A distinctive feature of the metal is the possibility of its recycling, which explains the relatively small volumes of production.

Today, world reserves are estimated at more than 55 thousand tons, and Russia ranks second in terms of gold deposits and production, 12.5 thousand tons, of which about 60% is metal of categories A, B, C1, suitable for industrial production.

Place of Birth

One of the largest deposits in Russia, one of the top five in the world ranking, Olimpiada, is located in the Krasnoyarsk Territory; gold mining here began in the 80s of the last century. The following regions of the Russian Federation belong to gold mining areas:

• Yakutia (Verkhoyansk and Aldan regions);
• Amur region;
• Eastern part of Siberia (Bodaybo, East Transbaikal, Yenisei and Prilensky regions);
• Far East;
• Primorsky Krai.

Gold in the total mass of the earth's crust is only 0.000001%; ​​it is a component of many chemical and physical substances, even in the human body, however, it is found in the earth in atomized form. And deposits of the precious metal are the places with the highest concentration. Such deposits are divided into two types:

• indigenous;
• alluvial.

Deposits of the precious metal of the indigenous type were formed in the bowels of the earth many thousands of years ago under the influence of magmatic processes. In such places, gold can rarely be found in its pure form; most often it is a component of a complex alloy.

Secondary or alluvial deposits were formed as a result of various types of impacts on primary deposits (chemical or physical).

As a result of the activity of microorganisms, temperature fluctuations, and under the influence of wind and water, the metal in the bedrock begins to descend into river valleys and settle there, forming a placer deposit. Here, gold is more accessible to mining, since the bedrock must be extracted from the ground, sometimes the depth of its deposits reaches several hundred meters. The largest Russian deposits of the indigenous type, of which the following can be distinguished:

Geographical location of the gold deposit, Sukhoi Lug

• Sukhoi Log;
• Berezovskoe;
• Vorontsovskoe.

The sites of significant gold deposits discovered in the Eastern part of Siberia were united into one mining zone - Sukhoi Log, industrial production here began in 1961 and continues to develop actively.

The deposit is one of the largest in Russia, however, its vein is characterized by a low metal content, and for gold mining to be effective it is necessary to process large volumes of earth rock. The average precious metal content is 2.7 grams per ton of ore, although there are places with a high gold content of up to 10 grams per ton.

The Berezovskoye deposit is unique; it was discovered in the 17th century, and the first significant mining work began in 1748. Since its foundation, about 140 tons of yellow metal have been mined here; it is dusty, small, it is classified as industrial grade C1 and C2, partial inclusions are noted in sulfide compounds, very rarely in the form of nuggets. However, according to expert estimates of specialists in the Berezovskoye field, reserves amount to 90 tons.

The Vorontsovskoye field is located in the Sverdlovsk region

The Vorontsovskoye deposit is located in the Sverdlovsk region, it was discovered in the 80s, but active gold mining here began at the end of 2000. The precious metal is represented by oxidized friable ores and gold-sulfide rocks.

The metal is found in the form of alloys with rock minerals, and in rare cases nuggets are found, but small ones, mostly up to 0.5 mm thick. This is the first deposit in the country where the technology of leaching metal from ore in winter was used, which made it possible to mine all year round.

Industrial mining

The main methods of gold mining on an industrial scale come down to extracting gold-containing ore to the surface. Depending on the depth of occurrence, this is carried out either by quarry, open-pit method, or by means of mines, they are called mines.

First, the upper layers of waste rock are removed, then, having reached the gold-bearing rock, it is loaded onto a special transport, which is delivered to the processing plants. In order to extract ore, it can be blasted or mined using equator buckets. At processing plants, the resulting pieces of ore rock are crushed into smaller ones and subjected to various processing methods:

• melting;
• electrolytic;
• extraction method;
• amalgamation method.

The process of gold mining in the Urals in detail

After crushing the rock, granular lead, alkaline sodium or potassium are added to it. This mixture is sent to the oven after keeping it to a certain temperature, then the process of leaching with water occurs. As a result of this, the waste rock and impurities are split and washed off with water, and the gold precipitates, but not completely pure, it still contains slags, which are removed with hydrochloric acid.

The electrolytic method of processing gold ore makes it possible to obtain a product of high purity. This method requires a cathode - pure gold in the form of a plate and an anode - hydrochloric acid (it includes chemical elements - Cu, Ag, Fe, Pd, Pt). Next, the electrolysis process is carried out, as a result of which the pure gold included in the anode is concentrated on the gold plate. The disadvantage of this method is the high energy intensity of the process, as well as the need for frequent electrolyte changes.

Method for extracting gold from brown and hard coals

Extraction is the most common method of beneficiation of gold ore. It is based on the use of various liquids that can break down the rock structure and release gold. The most commonly used are diethyl ether and hydrochloric acid solution.

After washing the ore (usually three cycles are enough), gold must be restored from the organic state of the substance to the metallic phase; this is done by keeping it in a hot solution of oxalic acid; the process lasts up to three hours. After all the procedures, gold is obtained with a high purity of 99.99%.

Until recently, the amalgamation method was the only available method for purifying ore from impurities and isolating gold from it, based on the use of mercury. It is able to attract gold particles, and when washed, the compounds settle to the bottom of the container. This method is quite simple and gives good results, but due to the high toxicity of mercury it is prohibited in Russia and a number of other countries.

Hydraulic gold mining method

The extraction of yellow metal in sea areas, river deltas, and swampy areas does not allow the use of machines and special equipment. In its place comes the dredge - a complex floating or stationary installation that is capable of removing soil from great depths - from 5 to 50 meters.

The dredge is a mechanized unit equipped with buckets that operate on the principle of a chain excavator. The main mechanism is installed on a floating platform, its dimensions depend on the size of the bucket - small, capable of extracting up to 100 liters and large - up to 250 liters at a time.

The dredge can be the size of a four-story apartment building and weigh up to 1,400 tons. On board the floating installation there is all the necessary equipment for washing sand or bottom rock; up to ten people can operate the largest dredge, and only one can operate the small one.

Dredging can provide high productivity, which previously would have required 12 thousand miners. Depending on the place of application, the dredge can be sea or continental. Offshore installations are based on keel vessels that can move either independently or under tow. Continental ones are built on the basis of a flat-bottomed vessel. In order for the dredge to work effectively, a sufficient amount of water is necessary, so during the period of shallowing of rivers it is impossible to use it.

Dredge for gold mining

Individual prospectors make homemade mini-dredges, they weigh up to 90 kg. For it they use:

• floating installation - some semblance of a boat or catamaran;
• engine;
• centrifugal pump;
• trench for washing sand;
• injector.

Using a pump, water enters the injector and is filtered; pebbles, sand, and gold-bearing rock settle on the washing grid, and the miner independently separates the yellow metal from impurities.

Non-commercial production

Artisanal gold mining is carried out by prospectors in places where industrial mining was previously carried out, as well as in places where its accumulation is insignificant and it is not economically profitable to build factories and processing plants.

In Africa, South America, and Asia, tens of millions of people are involved in artisanal fishing. Prospectors use manual mining technology, using a tray, which was invented several centuries ago, since the development of this fishery, and, oddly enough, is still relevant today.

The fact is that on an industrial scale, gold mining is carried out only in large deposits and mainly of the indigenous type, and for placer deposits they use dredges and private miners. In some places there is no point in using expensive equipment, and mining companies use individual miners using manual sand washing in a tray.

In Russia, independent fishing is prohibited by law; its implementation requires a license, which is almost impossible for an individual entrepreneur to obtain. Therefore, they get out of the situation by concluding labor contracts with large enterprises that have this permit for mining activities.

The manual technology of gold mining using a tray is quite simple. In the area of ​​the proposed placer on the banks of rivers, prospectors scoop up bottom sand and wash it under the running water of the river. Gold, even the smallest size, settles at the bottom of the so-called mining moss - a vinyl corrugated coating that traps gold particles, and waste rock and sand are washed away.

If gold ore has large accumulations of tiny particles, you can use chemical purification methods - amalgamation, cyanidation, leaching, but these are quite expensive methods; due to the high cost of the reagents and the low concentration of gold in the rock, they are not used by individual miners.

Video: How gold is mined