How are diamonds mined?

Diamond stands out among any other natural substances with extraordinary hardness, and is also quite rare. These and other extraordinary properties make this rock very popular throughout the world. Because it is important to know how they are extracted in nature.

The paradox of diamond is that it is very hard, although it consists of carbon. The same carbon, with only a different crystal lattice, forms graphite (the softest of rocks). All diamonds that are mined are formed by extremely densely combined atoms. Exceptional strength does not prevent the mineral from being brittle: with a sharp blow, the crystal breaks. It is believed that the emergence of diamonds occurred at a depth of tens or hundreds of kilometers, for hundreds of millions of years.

Most often, to mine diamonds on an industrial scale, they look for kimberlite pipes. These geological formations are named for the city of Kimberley, in South Africa, where this type of deposits was first discovered. The formation of the mineral in the depths of the earth occurs at very high temperatures and pressures. The final version of the origin of diamonds has not yet been developed by science.

Geological structures in which diamonds are found are gradually destroyed by wind and water. Crushed stone, pebbles, gravel and other surrounding rocks move. There are only assumptions of varying degrees of reliability. As a result, loose deposits are formed. Another type (but much rarer) is a particularly solid form of carbon that appears in places where meteorites fall.

In each of these cases, there is a number of shades, however, it is important to pay attention to the value of specific colors. Rare (and therefore valued) transparent blue, green and pink color. The cost of 100% colorless stones is even higher.

Regardless of which version these or other specialists adhere to, they all agree on one thing: the important stages of the formation of a stone take place at great depth. From there, along with the magmatic currents, the substance goes up. At a certain point, explosive tubes actually appear. The depth of their occurrence does not exceed 1500 m.

All almost know about the industrial production of diamonds in Yakutia and South Africa. But also it is conducted:

• in the Arkhangelsk region;
• western Australia;
• Canada;
• Congo;
• Botswana.

Alluvial mining is practically non-existent. They play only a small role in the global supply of rough diamonds. And the stability of the supply of mined products is questionable. The open way (career) is usually practiced when extracting diamonds from a depth of 600 m or less. In the deeper tubes, the diamond raw material can be extracted mainly with the help of mines.

Construction of mines are trying to postpone until the last moment. Usually these are areas either in the permafrost zone, or in especially hot areas. Often at great depths in the workings it is required to continuously pump groundwater. Breed from quarries and then from mines in large trucks are transported to factories. There, this raw material is cleaned with water.

Modern quarries have reached almost the maximum depth at which they can go.Experience has shown that the small width of production and the steepness of the sides further complicates the matter. From the very beginning, they plan to extract diamonds by open method with a breakdown by stages. This technique makes it possible to more often track changes in rock properties and production as a whole. Accordingly, it is easier to choose the best ways and patterns of work.

To choose the right parameters of the board at the very beginning of development, you need to use exploratory wells. The samples extracted from there are subjected to physico-chemical tests according to a special program. Additionally, experience is taken into account when developing similar quarries. The contours of the sides optimize the design. They can not be very hollow, otherwise the work is very complicated.

For all intermediate contours, the properties of rocks are continuously refined, taking into account the samples taken from each batch. Sometimes field tests are practiced right in the board of the quarry. Special attention is paid to assessing the degree of cracking of rocks. Additionally, learn how they behave on steep slopes. The angle of inclination of the real side is laid in projects from 50 to 55 degrees.

Usually the process takes months, but sometimes stretches over several years. Be sure to use special calculations. Only they allow us to conclude where the solid deposits are located, and where random finds are made.

Both quarries and mines or mines are most often built in hard-to-reach places. Therefore, residential and industrial infrastructure is being created around. There are a number of examples where the field became a city-forming facility for a fairly large city. Since it is unprofitable to sell raw materials in their pure form, processing plants are being built. Diamonds, finally separated from the waste rock, are brought to the cutting enterprises.

Cutting is also naturally being arranged nearby. The deeper the deposits, the more money they will have to invest in their development and field development.

For a very long time, diamonds and diamonds could be obtained only from India. But no matter how rich the natural processes were postponed there at the time, by the end of the 17th century these reserves had already been largely exhausted. Productivity dropped sharply. However, the development of technology has allowed to reverse the situation. The situation after the discovery of kimberlite pipes has changed dramatically.

To understand more deeply how mining takes place, we must return to the question of the appearance of diamonds in nature. The prevailing theory is that they form at depths above 100 km, where very high temperatures and pressures develop. Up the rock rises in the process of volcanic eruptions.

It is possible to find suitable objects and set up production on them only at substantial costs. Already the preparatory process is expensive, complex and long. It is estimated that over 1000 kg of rocks have to be processed to extract every 2 carats of rough diamonds. Careers are first created by blasting. They drill holes and put explosives in there, then crush the rock in layers.

The deepening of the workings is made until the extraction of minerals stops. A big problem is the separation of valuable raw materials from ore. The following approaches are used:

• the work of the fat installation;
• search for the desired crystals in X-rays;
• rock immersion in special suspensions.

The fat method involves mixing the extracted rock with water, and then pouring it onto a greased surface. Crystals are preserved in fat. A more advanced technique is x-ray transmission. In most cases, the suspension method is used. In a fluid with a higher density, drowned rock is drowned, with pieces of carbon on the surface.

In the recent past, Brazil and then Australia were the leaders of diamond mining. But Australian diamond deposits are gradually exhausting themselves. Angola is among the top six countries. However, in Canada, Botswana, many more valuable gems are extracted.

Both placers and mines are quickly developed. We have to systematically update the network of mines and quarries. The deeper the same career, the less likely to find a significant amount of raw materials. Therefore, an increasing number of quarries more than a kilometer deep is closing due to unprofitability. The mining method of mining is more complex and dangerous; however, it is economically advantageous.

The largest diamond deposit in our country is Mir in Yakutia. It has been developed since the late 1950s. From 1957 to 2001 mine was mined for $ 17 billion there (at current prices). To ensure such a result, we had to crush, lift and take out approximately 350 million cubic meters. m. waste rock. By the end of the 1990s, the magnitude of production reached such proportions that the dump trucks from the point of production to the warehouse had to travel 8 km. In 2001, due to the excessive complexity of the quarry had to be suspended.

And in 2009, the use of the Mir mine began. The water circulating under the ground is not just pumped out - it is redirected through pipes to special faults discovered by geologists nearby. During 2013, the field gave another 2 million carats of excellent technical quality diamonds. The company operates 7 days a week, the duration of mining shifts - 7 hours.

Combine harvesters used at the mine are equipped with arrows with milling crowns. The teeth, although made of hardened metal, are subject to very heavy wear. Therefore, each shift starting to work inspects the working part of the tools. If necessary, replace it immediately. The crushed rock is moved to the exit from the mine with the help of conveyor belts.

In a number of diamond mines, separate bottom parts are left intact during development. Their thickness can reach several tens of meters. If these structures were developed, it would be practically impossible to avoid flooding the fields. Additionally, layers of waterproof materials are used for protection. The movement of rocks in mines and quarries is carried out with the help of colossal trucks (sometimes with a capacity of more than 100 tons).

In the past, the situation was completely different. Up to the XIX century, no mechanical devices were used. The “queen” of diamond mining was an ordinary mountain shovel or pickaxe. Sometimes they simply paddled river sand and manually passed it through a sieve. But such methods have long lost their expediency.

And among the two methods - career and mine - the second option is more attractive. Much attention in the daily work of diamond miners is given to safety rules. No one is allowed under the ground without a helmet with a built-in lantern and without a self-contained breathing apparatus. It is strictly forbidden to leave it on 3 meters away from you. Be sure to settle down ventilation, through which it is normal to breathe under the ground easily.

Russian diamond mining enterprises (especially located in Yakutia) are perhaps the most high-tech in the world. They use vehicles designed for very severe frosts.Very strict temperature requirements are imposed on other equipment. It is believed that a new field can be put into operation from scratch for 3 or 4 billion dollars. Whether this amount includes the cost of the primary geological search - no company reports.

But later, when the quarry or mine is ready, it will be much cheaper to use them and develop the mine. The greatest difficulty with the underground method is the maintenance of an optimal working environment. The main trunks for lifting rocks can be used in case of accidents. Recreational niches are being prepared in various places of the mines.

For information on how diamonds are mined in Russia, see the following fideo: