Hello, our diamond readers! Diamonds have always attracted royal attention. You see them in photographs, exhibitions and jewelry houses and stores, as they like to say now, “in packaged” form. Have you ever been interested in how diamond mining occurs in Russia and around the world? After reading the article, you will find the answer to this question.

How are deposits developed? What are the different mining locations? What types of mining are there? What is a kimberlite pipe? Where do the most expensive and valuable diamonds come from? Who is the leader in terms of deposits and the main countries for diamond mining? All this and some more interesting facts and secrets, you will learn after reading.

Therefore, let's not hesitate and plunge into the world of mining some of the most expensive minerals on our planet. We are sure that reading the article will be interesting! We wish you pleasant reading!

Diamond mining: how minerals are extracted from deposits

Perhaps this issue should be considered at the very beginning. If you understand how diamond reserves are developed, then based on this you can determine those countries and states that can do this. The extraction process is not only labor-intensive, but also costly in terms of financing, since equipment for extraction and exploration does not cost 100 rubles.

So, a step-by-step description of the process of field development:

How and where to find diamonds? In most cases, the most long-term stage. Exploration of the future deposit. Can be produced over several years. Exploration of reserves, first of all, must answer fundamental questions on which the feasibility of investing funds will depend:

the amount of mineral reserves found and the method of extraction at the deposit. The cost of future investments depends on this;
climatic conditions. Without a doubt, extracting minerals in harsh and frozen lands or in the Arctic Circle is much more expensive and energy-intensive than in places with a hot climate. You should also take into account the depth, since sometimes deposits can be located under the thickness of ocean or sea waters. If the discovered deposit does not cover these costs in the calculations, then it is, as a rule, marked on maps and left until better times (until the reserves reach a “justified” limit in terms of investments or until the cost of development becomes cheaper, or until the reserves in other mining sites);
possibility of providing infrastructure and establishing a logistics line. It can also significantly influence a positive decision (fuel is now expensive all over the world);
payback period. Essentially, this is a theoretical calculation of profitability. Includes the calculation of the previously described and other expenses and the calculation of the possible profit from the treasures stored in the depths.

If everything went well and the development is profitable, then after completing the necessary documentation and all sorts of bureaucratic papers and permits, you should proceed to the second stage.

Beginning of development and tightening of infrastructure lines. So the process begins... The global purchase of equipment, materials, the construction of premises for workers, the installation of electricity, the construction of internal roads on site, and so on and so forth... Also during this stage, the establishment of a logistics line takes place. Many field development companies, as a rule, have their own permanent logistics partners, with whom all that remains is to negotiate the price and schedules of transportation and delivery. After the “working” site of the site has been prepared, the search for the deposit’s reserves begins and, in parallel, the third stage is launched.
Factory production stage. In order not to mine the ore from which diamonds will be “selected” far from the place of birth, factories and production facilities are often located near the deposit. Such costs pay off quickly, since it is easier to process a mineral close to the site and then produce the finished product, than to transport unprocessed ore far away to production and only then begin searching for it in the ore and subsequent processing.
Development and full-time work. This is the most basic stage. Full-fledged work begins over a long period of time. From several months and years to several decades (this is determined at the exploration stage).
Completion of work. Essentially, after a field has produced all its reserves, it must be “frozen.” That is, remove all constructed structures, take away equipment, fence off the area and close all the “holes” through which ore was mined. For example, after an oil well has been drilled, the dug shaft is concreted. Unfortunately, things don’t always happen this way, as this also requires costs. Therefore, in most cases you can see just an abandoned mine with the remains of garbage.

Types of deposits in the world

Diamond ore, like other ores, can be mined in several ways. There is nothing complicated here, since these processes have been known for a long time. But technology does not stand still and new types of reserve development are emerging.

The most popular way is open. You can also find another name - quarry. It's very simple. A significant reduction in development costs is achieved due to ease of production and high productivity. The least amount of labor and energy resources is spent.

Excavation of the quarry begins and as the deposit develops, it deepens into the depths of the Earth's interior. The open method includes the so-called kimberlite pipes, which we will talk about separately a little later, since they deserve special attention.

An equally popular method is closed. It is also called mine. It is used when open-pit mining is not effective and profitable. There is also a deepening into the bowels of the earth's crust, but through mine paths.

It is a more dangerous method, as there is a possibility of encountering accumulations of explosive gases, which can lead to an explosion, collapse or suffocation of workers. There is also a high probability of collapses and flooding if the ceilings are poorly secured. Therefore, since ancient times, miners often carry birds with them in a cage and go down with the dogs.

Unlike people, animals have left themselves more developed instincts, which helps everyone quickly detect the awaiting danger. Animals have saved the lives of many miners more than a dozen times.

Combined. Some deposits allow for both quarry and mine development.
Marine prey species. Extraction occurs from the bottom of a body of water, most often sea or ocean. A relatively recent type of mining in the world. Requires expensive equipment and sometimes special robots.

Kimberlite pipe: another interesting fact

In short, these are the places that provide us with diamonds by 90 percent, as they are the primary diamond deposits.

The kimberlite pipe takes its name from the place where it was first discovered. This happened on the African continent in the province of Kimberley. This is where it all started. Development and production took place from 1886 to 1914. On at the moment this deposit has practically exhausted itself. For an idea of size and scale: the total area is 17 hectares, the perimeter is 1.6 km, the depth of the quarry pit is 240 meters. This tube can be seen from space. Her scope is amazing.

In its shape, it resembles a glass of champagne rather than the pipe itself. Pipes form in places of ancient and stable earth platforms (some information from the theory of movement and creation of crustal plates), where volcanoes used to be. In places where there was a breakthrough of magma and its instantaneous cooling due to temperature changes and pressure differences.

Why do minerals choose such powerful platforms rather than thinner ones? This still remains a mystery. The ore that is mined from it is called kimberlite. In this form of deposit there are not only diamonds, but also other minerals, also expensive and rare.

Currently, the largest quarry for the extraction of diamonds and other minerals is located in Yakutia at the Zarnitsa deposit.

The opening and start of work was in 1954. The remaining reserves at the bottom of the pipe are now being mined using a closed method. It is estimated that mining will continue to be developed for more than thirty years.

The Mir kimberlite pipe is also famous throughout the world. Harsh climatic conditions and permafrost brought their own challenges during development. From the very beginning until 2001, so many diamonds were extracted from its reserves that their approximate total value today is $17 billion. Now it is also closed.

Kimberlite pipes are constantly being discovered in new places. They are constantly being explored and developed.

Secretly, the rarest diamonds are created when exposed to sudden and high temperatures and a sharp and instantaneous differential pressure drop. These conditions occur when a meteorite hits the earth's crust. It should be assumed that the impact of the Tunguska meteorite could also have produced rare diamonds that remained “in the depths of a mysterious history.”

Synthetic diamonds: a myth or a replacement for natural reserves

Diamond, like most natural compounds (graphite, plastic, gasoline, etc.), is carbon. The only difference is in the number of bonds between the elements and in the structure of the crystal lattice. Modern technologies and discoveries in science make it possible to replace some elements, for example diamonds, with products obtained experimentally using a synthetic method.

Synthetic diamonds can completely replicate the structure and look beautiful, but they are not yet able to replace diamonds obtained by natural methods. It is very difficult to repeat many miracles of nature. They are inferior in strength and play in the sun. The most famous are moussanite and cubic zirconia. And that's good. After all, you will probably agree that if it is possible to replace a laboratory-obtained element with an original, the latter will lose all value.

Despite this, synthetic diamonds have found diverse applications in many industries. They help improve the quality of goods and services at low cost.

Today's leading diamond mining countries

The first country where diamonds were found was India. Deposits were also found in Brazil. However, after a short period of time, they lost their positions.

The specific conditions necessary for the formation of diamonds make their deposits rare. The main and world leader is Africa, and more precisely, Congo, South Africa and Botswana (the recently declared leader).

Russia is in second place. The vast majority of deposits are located in Yakutia.

However, it is worth considering that the search for diamonds does not stop. Deposits have recently been found in Australia (where the rarest purple diamonds are currently mined), as well as in northern Canada.

The world is constantly exploring for diamonds and other precious deposits. Any topic related to diamonds is so interesting that we can talk about it endlessly. But, unfortunately, it’s time to part ways for a while. Thank you very much for your interest and attention! We are sure that you were interested and that you did not waste your time. Don't forget to recommend this article to your friends to read social networks, we will be very grateful!

Team LyubiKamni

Diamond deposits are characterized by limited distribution in the bowels of the earth. They are represented by the so-called placer and primary deposits. Placers are loose or cemented clastic deposits containing diamonds.
Diamond placers were formed in different geological eras. The most ancient of them date back to the Proterozoic time (about 2 billion years ago). Placers of this age are known in South Africa (in conglomerates of the Witwatersrand system), in Ghana (Birima), and in Brazil (Bahia, Minas Gerais). Placers of Cambrian-Silurian age (570-420 million years) are known in India. In the Urals, diamonds were found in Ordovician (450-420 million years old) gravelites, in Brazil and Bolivia - in Carboniferous (320 million years old) glacial deposits. In Yakutia, individual finds of diamonds are known in Permian (270 million years) and Jurassic (185 million years) deposits. In Brazil, Cretaceous deposits are known (140-100 million years), in Australia - Tertiary (70-10 million years). The most widespread, and the main ones in terms of industrial importance, are placers of Quaternary age (up to 1 million years). They are being intensively developed in Russia, Congo, Ghana, South Africa and others.

Geological structure of diamond deposits

According to their origin, diamond placers are divided into eluvial, deluvial, alluvial, coastal-marine and aeolian.

Eluvial placers lie at the site of formation, i.e. directly on upper parts primary deposit, and are a product of its destruction.
Colluvial placers occur on slopes. The material, which includes diamonds, has been somewhat displaced from primary sources, resulting in a weak roundness.
Alluvial placers are formed in river valleys by the transport and deposition of clastic material (pebbles, gravel, sand) and diamonds contained in it by water flows. Depending on the location of placers to certain elements of a river valley, alluvial placers are divided into channel, spit, floodplain (valley), and terrace. Channel placers of diamonds are located directly in the river bed. They are constantly being washed away, being under the influence of water flow and moving downstream. There are areas in river beds where, due to peculiar conditions easy the material is removed, but heavy minerals and diamonds remain in place. Within these areas, enriched placers are formed. Spit placers are placers occurring on pebble spits, islands and shallows. Diamonds they are distributed very unevenly. The main part of diamonds is concentrated in the head and middle parts. Valley placers are placers confined to a floodplain or first terrace, where diamond-bearing layers of sediments occur in the form of strips that do not depend on the direction of the modern watercourse. The placers are at a stage of relative rest; they are rarely eroded, since they are usually covered by rock that does not contain diamonds (loams, sands, clays). Terrace placers are placers confined to terraces, i.e., areas on the slopes of a valley, rising at a height of several to 70 m or more above the modern riverbed. The latter are the remains of ancient riverbeds.

Proluvial (spoon) placers occur in the valleys of ravines and small rivers and are formed due to the movement of detrital diamond-bearing material during floods or in watercourses after heavy rains. Diamonds in placers of this type are distributed unevenly due to the short-term action of water flows.
Coastal-marine placers occur along coasts and are confined either to coastlines (modern and ancient) or to the coastal shelf zone. Their formation is associated with the transport of diamonds by rivers to the coastal zones of the sea basin or with the erosion of older diamond-bearing deposits by waves. There are coastal (beach) placers, confined to coastal ramparts and the beach, and terraced ones, associated with sea terraces.
Aeolian placers are created as a result of the processing of other types of placers by the wind. They have no practical significance.

Placers of mixed origin are known.

Primary diamond deposits

Studying diamond placers led to the discovery of their original sources. As indicated, the first primary deposit was found in South Africa in 1870 near the village of Kimberley, from where the rocks hosting diamonds were called kimberlites, and the geological bodies they formed, depending on their shape, were called kimberlite pipes, kimberlite dikes and kimberlite veins.

Kimberlite pipes are cylindrical bodies, the diameter of which ranges from 25 to 800 m. The latter usually decreases with depth. There is no exact data on the depth of the tubes. One can only assume that it is at least 2-5 km.
Kimberlite dykes are bodies bounded by parallel walls. They were formed as a result of the filling of vertical or inclined cracks in the earth's crust with kimberlite rock. In addition, at depth, some of the kimberlite pipes transform into dikes, which has been established in several cases by mining. The thickness of kimberlite dikes is small - from 0.2 to 6-10 and less often more than 10 m.
Kimberlite veins are irregularly shaped bodies that were formed as a result of kimberlite cracks of various shapes and sizes, with a thickness of 1-2 m.

Kimberlite- This is an igneous rock, poor in silicic acid and with slightly increased alkalinity. It consists mainly of serpentine, olivine and mica. In addition, diamond, garnet (pyrope), ilmenite, chrome diopside and other minerals are found in kimberlites. True, these minerals are not necessarily present in all kimberlite bodies. For example, diamond-bearing pipes are mainly kimberlite pipes. The veins and dikes contain almost no diamonds. In addition to the listed minerals, kimberlites contain fragments of various rocks - both those occurring at depth and rocks among which kimberlite bodies occur. The content of the latter sometimes reaches 60-70%.
There is still no consensus on the origin of kimberlite magma. Most researchers are of the opinion that kimberlite magma has a deep origin, that is, it was formed at a depth of approximately 60-100 km from the surface, and this magma penetrated into the upper layers in places where kimberlite rocks are distributed along tectonic cracks.
To date, more than 600 kimberlite bodies have been found around the globe. Their study made it possible to outline some patterns in their placement. Firstly, the main primary diamond deposits are confined to ancient platforms, i.e., to areas of the earth's crust that are characterized by a two-tiered structure. The lower tier consists of crystalline rocks crumpled into folds, the upper one - of horizontally lying sedimentary and volcanogenic rocks, the thickness of which reaches 3-5 km.
It is in such areas that the primary diamond deposits of Yakutia, South Africa, and India are located.
Secondly, within the platforms, the primary diamond deposits are mainly kimberlite pipes and, in some cases, kimberlite dikes. Of the more than 600 kimberlite bodies, less than half are diamond-bearing, with increased concentrations of diamonds noted in only 6-10% of the bodies.
A detailed study of kimberlite bodies shows that their formation did not occur in one stage and was multi-stage.
The sequence of formation of kimberlite bodies appears to us as follows:

some kimberlite minerals (olivine, pyrope, ilmenite, apparently partly diamonds) were formed at great depths;
the formation of individual kimberlite pipes could not occur immediately from the first magma chamber, but in stages, and such magma chambers repeatedly moved upward;
Next comes the intrusive stage of direct introduction of kimberlite magma into the upper floors. At this time, kimberlite dike veins and some pipes are formed;
in the upper platform sedimentary strata, the intrusive stage is followed by an explosive (explosive volcanic) stage. The latter is distinguished by the short duration of its active activity. Along with the breakthrough of the host rocks, some of which are subject to crushing, the kimberlites formed at the first stage are also subject to crushing, followed by cementation with subsequent portions of kimberlite material. In this way, kimberlite breccia is formed, and explosions could be repeated.

The formation of another part of the diamonds found in kimberlites should be associated with this period. There are various hypotheses regarding the conditions under which diamonds are formed in bedrock deposits. One of the most common is that diamonds crystallize from magma at great depths. This hypothesis was developed by A. S. Fersman, V. S. Sobolev, Williams, A. du Toit and other scientists. Recently, researchers V.G. Vasiliev, V.V. Kovalsky, N.V. Chersky, when studying the diamond deposits of Yakutia and the results of obtaining artificial diamonds, have expressed a different point of view, claiming that diamonds were formed in special centers located in the thickness of sedimentary rocks platform cover (upper tier of the platform) or in the boundary zone of the upper (sedimentary) and lower (folded crystalline basement) tiers of the platform. The thermodynamic conditions necessary for this (high temperature and pressure) were provided due to explosive processes resulting from the accumulation in the source of a mixture of explosive gases coming from the host rocks. And since carbon is necessary for the formation of diamond, it is assumed that it was brought from oil- and coal-containing rocks in the form of hydrocarbons.
It is most likely that in nature the crystallization of diamonds occurred in different conditions. One part of the diamonds was formed during explosions in the intermediate centers described above, the other - from a magmatic melt in the deep zones of the earth's crust.
In addition to the finds of diamonds in kimberlites, single diamonds were found in fragments of pyroxene-garnet and garnet-olivine rocks found as inclusions in kimberlite pipes.
The degree of diamond potential of individual kimberlite bodies largely depends on their structural and spatial position. Most of them gravitate to the junction zones of syneclise (extensive gentle deflection of the layers of the earth's crust within the platform) and anteclise (extensive gentle uplift of the layers of the earth's crust within the platforms), where large faults apparently developed. The specific reasons for the spatial distribution of diamond-bearing and non-diamond-bearing pipes have not yet been clarified and require detailed research.
Within some folded areas (Urals, Eastern Australia, Kalimantan), diamonds were found only in placers. There are no kimberlites. The primary sources here are considered to be ultramafic rocks, mainly peridotites. All known diamond-bearing bodies of this type are of no industrial importance.

Diamond deposits in the Republic of Sakha Yakutia

Diamonds from Yakutia have now taken a firm place in the country's economy. In 1949, only the first diamonds were found on the river. Vilyue, and already in 1954 - the first cmberlite pipe with diamonds. To date, large primary diamond deposits have been discovered, such as the Mir, Aikhal, and Udachnaya pipes.
Every year, diamond production increases significantly.

Kimberlite pipes of Yakutia

On the territory of Yakutia, bedrock and placer rocks are known diamond deposits. The only primary sources of diamonds in Yakutia are kimberlites. They are located along the marginal parts of the Siberian Platform at the junction of large structural and tectonic elements
(Anabar anteclise and Tunguska and Vilyui syneclises, Anabar anteclise and the Verkhoyansk and Leno-Anabar troughs). Kimberlite pipes in these zones often show a linear arrangement, indicating their connection with zones of deep faults (disturbances in the earth's crust).
Five areas of development of kimberlite bodies are very clearly distinguished. They differ from each other in their geological structure, varying degrees of diamond content of kimberlites, their composition, and sometimes age.
Malo-Botuobinsky district. This area covers the basin of the well-known river. Malaya Botuobiya (a tributary of the Vilyuya River) and is characterized by a rather simple geological structure. The most ancient rocks exposed on the surface are the gypsum-bearing marls of the Upper Cambrian. These deposits are replaced by sandy-carbonate and clayey-carbonate rocks attributed to the Lower Ordovician. The latter are widespread and are the main ones in the geological context of the region. The eroded surface of the Lower Paleozoic rocks is overlain by sandy deposits of presumably Carboniferous age and continental sandy-clayey deposits of the Lower Permian. Both of them are preserved in the form of small spots in the north-west of the territory.
The Lower and Middle Paleozoic deposits are intruded by igneous rocks of the trap complex, attributed to the Triassic.
Mesozoic deposits are represented by continental sandstones and conglomerates of the Lower Liassic, lying on the eroded surface of all the above-mentioned older sedimentary and igneous rocks. The formations of the Lower Liassic are overlain by coastal-marine clayey-calcareous-sandy deposits of the Middle Liassic.
At the base of the Mesozoic section lie Ratleyassic sand-gravel-pebble deposits and kaolinite clays. They are known in the basin of the middle reaches of the river. Irelyakh, where they were preserved in the form of a small spot on a flat interfluve composed of Lower Ordovician carbonate rocks.
Quaternary deposits of various origins are widely developed in the area.
The primary diamond deposit in this area is the well-known Mir pipe, discovered in 1955. By the nature of the geological structure, it is a vertically extending pipe-shaped body, composed of brecciated rock, consisting of fragments of kimberlite itself and various inclusions of other rocks and minerals; in plan, the pipe has the shape of an irregular ellipse, elongated in the northwest direction 29). With depth, the diameter of the tube decreases. It is made of kimberlite breccia - a rock consisting of fragments and grains of olivine, pyrope, ilmenite, chrome diopside, serpentine, and related inclusions breed(altered peridotites with pyrope, olivinites, serpentinites) fragments of rocks pierced by a pipe and foreign inclusions (mainly Paleozoic carbonate rocks) and a cementing groundmass consisting of a fine-grained aggregate of serpentine and carbonate. the amount of clastic material fluctuates in pre-tubes 80%. The kimberlites of the near-surface part of the Mir pipe are greatly altered and form a number of zones that differ in the nature of decomposition and color.

The upper part of the pipe is represented by destroyed kimberlites. In the exploration pits, the following section is observed: from the surface to a depth of 1.5 m, an eluvial layer composed of clayey sand and kimberlite gruss with fragments of solid kimberlite, limestone and diabase. These deposits are greenish-gray in color. At a depth of 1.5-2 m, these deposits are replaced by heavily destroyed kimberlite, which is represented by loose and woody rock of greenish-gray, yellow-green, dark green and sometimes
bluish flowers. The rock is rich in blue-green chlorite, pyrope and to a lesser extent ilmenite. With a depth of 4-6 m, kimberlite becomes more massive and gradually turns into dense monolithic rocks.
By external signs In the Mir kimberlite pipe, fine-clastic, coarse-clastic, spherical, dense and other varieties of kimberlite are distinguished.

Diagram of the Mir tube

It has been established that the diamond content in the Mir pipe is significant. Diamonds are distributed throughout the pipe, despite its heterogeneous structure (various varieties of kimberlite). The size of the crystals is also almost the same throughout the tube. Both small and large diamonds can be found here and there.
The Mir pipe, as many believe, was formed in the Middle Triassic (200 million years ago). From then until the present period, it was eroded to a depth of about 300-350 m. The liberated mass of diamonds in the etholl turned into placer deposits.
In addition to the Mir pipe, four more kimberlite bodies were found in the Malo-Botuobinsky region. However, their industrial value is not the same.
The Daldyno-Alakitsky district is located in the basin of the upper reaches of the river. Markhi (left tributary of the Vilyuya River). The area is composed of a uniform complex of carbonate rocks (limestones, dolomites). In a number of places, these deposits are intruded by sheet intrusions and trap dikes, as well as kimberlite pipes. The latter are grouped in an area whose size is 25X60 km. The most famous and richest are the Udachnaya and Aikhal pipes. The first of the pipes found in Yakutia, “Zarnitsa,” is also located here.
Kimberlites in the Daldyn-Alakit region are represented by two varieties: kimberlite breccia (breccia - rock, consisting of cemented angular fragments) of light gray and greenish-gray colors and weakly brecciated dark green kimberlite of porphyritic appearance.
In total, there are more than two dozen kimberlite pipes in the area. Half of them are diamondiferous. The diamond content in them varies.
Kimberlites in this area appear to be of different ages. The presence of pre-Permian and post-Permian (Middle Triassic) kimberlites is assumed. The kimberlite pipes, from the time of their formation to the present day, have been eroded to a depth of about 200-400 m.
Varkhne-Munsky district is located in the upper reaches of the river. Muna (left tributary of the Lena River). Its geological structure is determined by the location of the area on the southeastern edge of the Anabar anteclise, where carbonate rocks of the Middle and Upper Cambrian emerge on the surface.
To date, more than 10 kimberlite pipes are known here, made of kimberlite breccias, tuffs and porphyritic kimberlites. Inclusions of Cambrian limestones, dolomites, crystalline shales, and mudstones were found in the kimberlites.
The age of the kimberlites of the Verkhne-Munsky region is assumed to be Triassic, by analogy with the pipes of nearby areas.
The cutting depth of the pipes in this area does not exceed 200-300 m.
Most kimberlite bodies are diamondiferous.

Oleneksky district covers the basin of the middle and lower reaches of the river. Olenek, the geological structure of the territory is quite simple. Carbonate rocks of the Lower, Middle and Upper Cambrian are developed here, intruded by dikes and sheet bodies of traps and kimberlites. More than 50 kimberlite bodies have been discovered in this area. Most of them are tubes, the rest are veins. The size of kimberlite bodies varies (from 20 to 500 m for pipes and 0.5-5 m in thickness for veins).
Most of the kimberlite bodies are made of porphyritic kimberlites, some are made of kimberlite breccias and kimberlite tuffs. In the kimberlites, xenoliths of Cambrian limestones, traps, crystalline gneisses and plutonic rocks - eclogites and peridotites - were found.
Materials to substantiate the age of kimberlites in the middle reaches of the river. Little deer. With a large degree of convention, we can talk about their Middle Triassic age. In the lower reaches of the river. Olenek collected data indicating a younger - Upper Jurassic age of kimberlites.
From then until the present period, kimberlite bodies in the middle reaches of the river. Deer are cut to a depth of 200-300 m, in the lower - to 1500-2000 m.
The vast majority of kimberlites in this area do not contain diamonds. In the middle reaches of the river. Olenek there are pipes with poor diamond content.
Alda, a certain area of kimberlite development covers the river basin. Chompolo. Cambrian carbonate deposits emerge on the surface here. There are seven known kimberlite pipes here, which in composition differ sharply from the kimberlites of the regions considered. They are characterized by a high content of pyrope, chrome spinels and chrome diopside. A characteristic feature of the Aldan kimberlites is the almost complete absence of ilmenite in them. Olivine is almost completely replaced by serpentine. The pipes of this area have not yet been sufficiently studied and there is no material available on their age and depth of cut. No diamonds have been found in them yet.
Placers on the territory of Yakutia are widely developed. However, rich placers are rare.
The following are known among diamond placers: ancient placers formed in distant geological periods and having no connection with the modern topography of the earth's surface. Clastic material and diamonds in them are usually cemented to form hard rocks (fossil placers). Young placers are associated with modern relief.
Among the ancient placers on the territory of Yakutia the following are known:
Permian placers(formed 270-300 million years ago). They are represented by thick (up to 13 m) conglomerates (cemented clastic rocks with rounded fragments). There are few diamonds in these placers, they are difficult to mine and therefore are unlikely to be of practical interest.
Rhet-Liassic proluvial placers have been preserved to this day in the depressions of the Malo-Botuobinsky region. The placer is small: 1.5-2.5 km wide and about 5 km long. The thickness of the placer reaches 0.1-2 m in the peripheral part and 30 m in the central part. Diamond concentrations vary in different areas. The highest diamond contents are typical for the lower parts of the placer. The placer is of industrial importance.
Jurassic coastal-marine Diamond placers were discovered in the lower reaches of the river. Lena. They are confined to conglomerates of small thickness (0.3-0.6 m). The placers have not been studied in sufficient detail. They have not been tested for diamonds. However, one cannot count on great prospects here. The richest areas of the ancient coastal strip, once located closer to the primary sources, have already been eroded, and the remaining areas of diamond-bearing horizons are insignificant in thickness and are covered by a thick layer of non-diamond-bearing rocks.
Young placers of Yakutia are more important industrially and are more widespread. Among them are:
Paleogene-Neogene placers confined to the so-called “watershed” pebbles. The latter are the remains of ancient river beds. They have little connection with modern rivers. Placers of this age are widely developed in the middle reaches of the Markhi and Tyunga rivers and on the left bank of the lower reaches of the river. Lena.

The pebbles to which the placers are confined lie on flat watersheds and reach in thickness
1-8 m. The pebbles are represented by rocks that are resistant to destruction (quartz, silicon, quartzites), which indicates their repeated redeposition, as a result of which weak local rocks completely collapsed and turned into sand and clay. Placers of this type are characterized by varying degrees of diamond content. They deserve further study, since industrial placers may be found here.
Placers of Quaternary age are confined to the valleys and terraces of modern rivers, to ravines, slopes and watersheds. The peculiarities of these placers lie in the fact that each morphological type clearly records a certain element of the earth's surface. For example, terrace placers are confined to deposits of high terraces, channel placers - to river beds, spit placers - to river spits, valley placers - to floodplains and lower river terraces.
Among Quaternary placers, eluvial, deluvial, deluvial-alluvial and alluvial genetic types are distinguished. Placers of alluvial origin predominate.
Eluvial placers are formed on diamond-bearing kimberlite pipes. They have a small thickness (from 1 to 4 m) and are represented by products of destruction of kimberlites. Placers of this type are known at the Mir, Udachnaya, Aikhal, and other pipes. Diamonds are scattered throughout the entire mass of sediments. Slightly higher concentrations were noted in its lower part.
Deluvial placers are distributed along the slopes near kimberlite pipes. They are represented by clayey, loamy and sandy loam deposits containing crushed bedrock. The thickness of the deposits is from 0.3 to 2 m. Diamonds are concentrated mainly in the lower horizons of the placer. The diamond content in colluvial placers is significantly less than in eluvial placers, and sharply decreases with distance from the bedrock source.
Industrial placers are known in the area of the Mir, Udachnaya, and Zarnitsa pipes.
Alluvial diamond placers are widespread in Yakutia. They are known in the basin of the upper and middle reaches of the river. Vilyuya, in the river basin
Markhi and Tyunga, in the basin of the left tributaries of the river. Lena in its lower reaches, in the basin of the Olenek and Anabar rivers.
Industrial placers are established in the basin of the Irelyakh, Malaya Botuobiya, and Daldyn rivers.
Among alluvial diamond placers, channel, valley and terrace ones stand out.
The most common and best studied type is channel placers.
The source of alluvial Quaternary placers are primary deposits and more ancient placers.
Terrace placers are confined to alluvial accumulations of I, II, III, IV, V and VI terraces above the floodplain, the height of the platforms ranging from 10-15 to 70-80 m above the water level in the channel. Diamonds in these deposits were found along all the rivers of Western Yakutia, where valley diamond-bearing placers are developed, but almost everywhere they are characterized by insignificant concentrations of diamonds. Exploration work on the rivers Vilyui, Markha, Malaya Botuobia, Molodo, Syungyude, Motorchuna and others has established a natural decrease in diamond content from the lower to the upper terraces. The most enriched are the placers of terraces I and II above the floodplain.
Currently, industrial concentrations of diamonds are known only for terrace placers of the river. Malaya Botuobia and its left tributary of the river. Irelyakh.
The structure of terrace placers is very similar to most of the diamond-bearing rivers of Western Yakutia. On the raft there is a layer of diamond-bearing pebbles with a thickness of 0.3 to 4 m. It is covered by unproductive sands and loams, the thickness of which ranges from 2-3 to 10 m. Diamonds are usually scattered throughout the entire thickness of the pebbles. The lower parts of the pebble alluvium are somewhat more enriched.

Valley placers are characterized by a constant structure and constant thickness of alluvium. They have the greatest industrial value and include placers of the floodplain and the first terrace, the diamond-bearing deposits of which lie 3-4 m below the modern water level. In the thickness of alluvium, two horizons are usually distinguished: the upper one is poor in diamonds or does not contain them at all), forming the so-called “peat”, and the lower one is the productive horizon, making up the so-called “sands”. Valley placers in Yakutia are widespread. They are known in the basins of the Vilyuya, Markhi, Tunga rivers, along the left tributaries of the river. Lena in its lower reaches, as well as in the basins of the Olenek and Anabar rivers. However, industrial concentrations are known only in the area of the Mir and Udachnaya pipes. Slightly higher diamond contents were noted in the valley placers of Markhi, Motorchuny, Molodo and others.
Channel placers in Yakutia are very widespread. They are the most well studied. Diamonds have been found in most rivers in the river basin. Vilyuya in the south and a number of rivers flowing directly into the Arctic Ocean. However, despite such a wide areal distribution of diamonds, riverbed industrial placers are established only in the river basin. Lesser Botuobia. Increased diamond content noted in the river basin. Markhi and other rivers.
The study of a large amount of material on the channel placers of Yakutia made it possible to outline some patterns in their structure and distribution,
Placers with increased concentrations of diamonds are located in close proximity to eroded primary and more ancient placer deposits, and the enrichment areas are not very large - from 5 to 10 and less often up to 25 km.
Diamonds are concentrated in areas of the riverbed where the highest speeds of watercourse currents occur.
The Yakut placers are characterized by extreme unevenness in the distribution of diamonds. Areas that are very enriched are replaced by areas that have very poor conditions. This is mainly due to the dramatically changing dynamics of watercourses caused by big difference river water flows at different times of the year. In winter, rivers freeze to the bottom and dry up in summer, but at the same time, in the spring after the snow melts and in the summer after heavy rains, there are large floods when the water in the rivers rises to 6-8 m, and sometimes more.

Diamond mining and deposits in Africa

1867 marked the beginning of African diamond history. This year, the son of Boer farmer Daniel Jacobs, playing with friends on the banks of the river. Orange, near Hopetown (South Africa), found a white pebble and brought it home. Jacobs' neighbor Schalk Van Niekerk saw this pebble and asked the owner to sell it to him. Jacobs did not agree to take money for the stone and simply gave it to his neighbor. Niekerk showed the stone to traveling salesman John O'Reilly, who agreed to sell it on the condition that he receive half the price. But O Reilly for a long time couldn't find a buyer. Finally, the private commission agent Lorenzo Bayes in Kohlsberg bought the stone and sent it for analysis to the mineralogist Atherston in Grahamstown. Atherston determined the diamond to be 21.73 carats. With O'Reilly's consent, Atherston sold the stone for £500 to the President of the Cape Colony, Budhaus, who sent the diamond to the Paris Exhibition.
But for a long time he was not given any importance from Africa. However, in 1869, a shepherd found a new diamond near the Zandfontein farm. It was a beautiful stone white weighing 83.5 carats, later named the "Star of South Africa" or "Dudley". Van Niekerk bought the diamond from a shepherd for 500 rams, 10 bulls and one horse, and he sold it to the Lilienfeld brothers in Hopetown for £11,200. The brothers resold the stone to Countess Dudley for 25 thousand pounds sterling. This diamond served as an impetus for the fact that in the area of the river. A mass of enterprising people who dreamed of getting rich quickly poured into Orange. The diamond rush has begun. In 1870, on the banks of the river. Vaal geologists discovered a rich diamond-bearing placer.

In the same year, diamonds were found in other places in South Africa. They were first discovered at the Jagersfontein farm, then at the Dorstfontein farm, and somewhat later at the Bultfontein farm. Moreover, the diamond was found in the cement that held the bricks together in the wall of this farm. In 1871, a very rich diamond deposit was discovered, which was first named Kolberg Kopje, and later renamed Kimberley - in honor of the English Minister of Colonies. Hence the name of the bedrock in which the diamonds were discovered - kimberlite. Kimberley became the center of the diamond mining industry in South Africa.
In 1890, the Wesselton diamond deposit was discovered 6 km from Kimberley. In 1902, diamonds were found in the Transvaal at the new Premier mine. It was here, on January 25, 1905, that the world's largest diamond crystal weighing 3106 carats, or 621.2 g, called "Cullinan", was found.
In 1925, placers were discovered in Little Namaqua Land, and in 1926, rich placers were discovered in the Lichtenburg area.
In 1887, diamonds were discovered in British Guiana (South America) while panning for gold on the river. Puruni. But industrial mining here began in 1890, when diamonds were found on the river. Mazaruni. From 1890 to 1910, 62,433 carats of diamonds were mined in British Guiana. In 1924, a rich placer was discovered near the river. Yuvang - a tributary of the river. Potaro, which significantly increased diamond production in the country.
The beginning of the 20th century was marked by the discovery of new major diamond deposits. And the first role again belongs to Africa.
In 1903, the first diamonds were discovered in the Congo on the river. Munindele - a tributary of the river. Lualaba, and in 1910 - in the river bed. Kiminina, near the Mai-Munene waterfall, then diamonds were found near the Chikapa and Luashilla rivers (tributaries of the Kasai River). Rich diamond placers along the river were discovered in 1919. Bushimai are still in use today. Systematic diamond mining in the Congo began in 1913.
In 1907, diamonds were discovered in Angola, in the river basin. Kasai and its tributaries. This is essentially a continuation of the deposits of the diamond-bearing region of the Congo. Diamond mining in Angola began in 1916.
Diamonds from the Republic of South Africa gave impetus to the search for them in other African countries. Exploration was especially intensive in South-West Africa. In 1908, during the construction of a railway in the Namib Desert near Luderitz Bay, a black worker found diamonds. They were subsequently found in other places in South-West Africa. The deposits, mostly alluvial, are located along the Atlantic coast from Conception Bay in a southerly direction with a length of 500 km. All the country's major diamond mining enterprises are located in this area.
In the 60s of this century, diamonds were discovered in South-West Africa seabed coastal strip of the Atlantic Ocean and their extraction is organized in the coastal strip from the borders with Angola (Kunin River) to Cape Columbine.
1912 gave the world another diamond-rich country on the South American continent; diamonds were discovered in Venezuela, in the river basin. Caroni. Industrial development here began in 1925.
1930 and 1943 New diamond deposits were discovered in the state of Bolivar, adjacent to British Guiana and Brazil.
In 1910-1912 they were discovered in Tanganyika in the Kwimba region near Mabuki, south of Lake Victoria, then near Shinyanga and on the Iramba plateau. Industrial mining in Mwadui began in 1925, and in the Shinyanga region - in 1928. In 1940, the rich Mwadui kimberlite pipe was discovered in the village of Lukhombo.
In 1915, diamond deposits were discovered in Equatorial Africa. The first diamonds were discovered near Ippi in Ubangi-Shari, in 1928 - in the Bria area, where mining began in 1931. In 1936, diamonds were found in the river basin. Sangi.
The history of the diamond mining industry in Ghana begins in 1919, when on the river. Diamond deposits were discovered in Birim. In 1922, a rich diamond-bearing area was found on the river. Bonza and in the river basin Birim.
Diamond production in the country increased over the year from 215 to 1,000,000 carats.
In 1930, the director of the Geological Survey of Ghana, Junner, discovered the first diamonds in Sierra Leone in the Bafi and Sewa river basin. In 1931, diamonds were discovered in the river basin. Moa. In 1934-1935 Diamond placers were discovered on the territory of Guinea, in the basin of the upper reaches of the river. Moa, then - on the territory of the Republic of Ivory Coast.

The Ministry of Finance of the Russian Federation, as a result of an open auction for the sale of special-sized diamonds weighing 10.8 carats or more on the domestic market, held on the territory of the Gokhran of Russia, sold stones with a total weight of 3.4 thousand carats for a total amount of about 12.8 million dollars, RIA reported News in Gokhran.

The first "C" is carat weight. At this stage there is precise definition the weight of the stone by weighing it on scales or calculating using formulas if the diamond is fixed in the product. The weight of a diamond is expressed in carats.

The second "C" is color. Completely colorless diamonds are quite rare, and almost all stones have shades of varying colors and intensities. The expert's job is to accurately determine the intensity and color of a diamond under standard lighting using color standards.

The third “C” is clarity (purity). At this stage, all internal imperfections (defects) of the stone are identified.

The fourth "C" is cut (quality of cut). At this stage, characteristics of the diamond’s shape, cutting quality and finishing are given.
Based on these parameters, one can judge how a given diamond stands out among other diamonds, on the basis of which it may be more expensive, or, conversely, cheaper.

The world leaders in diamond mining are Africa and Russia. The main African diamond-producing countries are Botswana, South African Republic and Congo (Democratic Republic), Angola and Namibia.

According to the Ministry of Finance of the Russian Federation, the volume of diamond production in Russia in 2008 amounted to 36.925 million carats with a total value of 2.509 billion dollars. The average cost of one carat of diamonds mined in the Russian Federation was $67.95.

According to materials from the Kimberley Process (as part of the Kimberley Process, the international community is fighting illegally mined diamonds in conflict zones, Botswana became the world leader in diamond mining in value terms in 2008. Diamonds worth $3.273 billion were mined in this country. Russia in production in value terms took 2nd place in the world. In the world ranking for production in carats (36.925 million), Russia took first place in the world.

The material was prepared based on information from RIA Novosti and open sources

Girls' best friends are diamonds, which are obtained, as is known, by processing. Carefully cut by traditional and modern methods gives these precious stones the dazzling brilliance that makes them so valuable. But first, diamond deposits need to be developed and the raw materials themselves must be obtained.

Diamond processing and mining bring considerable income to those who do it. But this matter brings with it considerable difficulties. Few people think about how many difficult steps a diamond nugget goes through before it reaches the counter of a jewelry store: mining by open and underground methods, sorting, washing, cutting... Not to mention how much time and chemical reactions are needed for a diamond deposit to form at all in the bowels of the earth. For those who are interested, we will tell you where diamonds are mined, and in particular we will describe the main deposit, and how diamond mining occurs in Russia.

Diamond deposits and their appearance in nature

Diamond, the hardest mineral both on our planet and in the entire Universe (at least the studied part of it), consists of carbon. Like its close relative - graphite, which, on the contrary, is characterized by a high degree of softness. The thing is that their crystal lattices differ greatly in density. All diamond deposits, with the exception of meteorites, were once graphite.

The transformation of the softest stone into the hardest on our planet occurs at very high temperatures(from 1100°C) and enormous pressure (35 kilobars and above) deep underground (from 100 kilometers). It is under such conditions that the crystal lattice becomes denser and diamonds are formed, which subsequently grow into entire deposits.

Of course, the stone cannot be mined at such a depth - it is too difficult to reach. Methods for extracting diamonds do not involve penetrating hundreds of kilometers deep into the planet, but searching for those places where they themselves come out closer to the surface and developing them. Are you already wondering where and how diamonds are mined? Then read on.

Places where diamonds are found and methods of their extraction

As a result of magma eruptions that occur deep underground, diamond deposits are pushed to the surface of the earth's crust and are located in kimberlite pipes. Their material, the mineral kimberlite, is named after the town of Kimberley in South Africa, where this phenomenon was first discovered. This rock contains precious crystals, which later become diamonds.

The largest diamond deposits were found in Canada, the already mentioned South Africa, and this stone was also found in Botswana, Namibia and Angola. The rarest is mined in Australia. But the largest volumes of diamonds (in 2014 – more than 38 million carats) are mined in Russia.

The Russian Federation is a recognized world leader in the diamond industry. For comparison, Botswana, in second place, produced 25 million carats in 2014 (). Moreover, 99% of all diamonds mined in the Russian Federation are Yakut.

But kimberlite pipes that come out as close to the surface as possible are not so easily accessible. Their usual depth is 1.5 kilometers. Therefore, they are difficult to detect and require a lot of means to bring the rock containing the crystals to the surface. This partly explains the high cost of diamonds - Working with diamond deposits requires a huge amount of financial, labor and time resources .

It takes one or more well-timed explosions to expose kimberlite rock and begin to extract minerals from it. Quarries up to 600 m deep are formed, from where so-called open-pit work is carried out. Closed, or underground, mining jobs go to mines that are located much deeper.

A mine is not an underground cave shimmering with all the colors of the rainbow. This image is more likely from an adventure novel or a Hollywood film. In fact, in underground mining, future diamonds are found among other rocks, which must first be washed, sorted and illuminated with X-rays. Under their influence, the crystals begin to glow.

But this is not the only way to extract them from ore:

Fat installations - the most primitive method. The rock, along with water, falls onto a flat surface, where a fat layer is also applied. Crystals stick to it, and the rest of the rock is carried away by water.
Use of suspensions - a much more convenient method. After processing the rock with a high-density liquid, the unnecessary raw material sinks, and gems- float up.

There is also a simpler method of extraction - from placers. Placers are much less common and are formed when kimberlite rock in the mountains is destroyed by weather conditions - rain, hail, snow - and the crystals, along with rubble and sand, roll down to the foot. Then they lie literally on the surface. Therefore, stories about beaches covered with diamonds are also true, although such deposits dry up very quickly. Since ancient times, diamonds have been obtained in this way - simply by sifting through crushed stone and sand by hand, selecting jewelry from there.

Application

Diamonds that are obtained from kimberlite pipes or placers are sent not only to the jeweler’s table, contrary to popular belief. Half of them, for some reason not suitable for cutting, are found technically. After all, this mineral is in great demand not only because of its charming appearance, but also because of its unique physical properties.

As already mentioned, it is the hardest stone in the Universe. Therefore, it is needed in construction and industry.

It makes excellent tools for cutting other materials. Even diamond chips applied to a file or disc of a grinding machine greatly increases their reliability and functionality. If you need to carefully cut or pierce any hard material, then you won’t find a better diamond for this task. It is even used to drill holes in other rock formations.

To reduce the cost of tools that use industrial diamonds, several methods were invented to synthesize them from carbon. Synthetic counterparts practically do not differ in quality from real ones, and much time and effort are not spent on obtaining them.

10th grade- theme “Mining industry”
7th grade- when studying the structure of the lithosphere and minerals
8-9th grade- in the study of minerals and the mining industry of the Russian Federation; especially in the topic “Far East”
7-10th grades- general level, for a holiday lesson before
International Women's Day

Top ten countries in the world
for gem diamond mining

Fifteen top countries in the world
for the extraction of jewelry diamonds,
2000, thousand carats *

1. Botswana 19,368
2. Australia 11,992
3. Russia 11,600
4. South Africa 4,300
5. Angola 3,914
6. Congo (Kinshasa) 3,500
7. Canada 2,558
8. Namibia 1,520
9. Brazil 1,000
10. Sierra Leone 450
11. CAR 346
12. Tanzania 301
13. Guinea 278
14. China 230
15. Ivory Coast 210

Top ten countries in the world for the production of artificial diamonds,
2000 (estimate), million carats*

1. US 248
2. Russia 80
3. Ireland 60
4. Japan 33
5. Belarus 25
6. Sweden 20
7. China 16.8
8. Ukraine 8
9. France 3
10. Greece 0.75

* Carat is a unit of mass used in jewelry making. 1 diamond carat = 200 mg.

Quests

1. Basic level. Remember the top five countries for gem diamond mining.
Good level. What famous diamond-bearing areas have you heard about? Try to roughly identify these areas on a map.
Creative level. Analyze the location features of the leading diamond mining countries. On which continent are most of them located? Using maps of the structure of the earth's crust, determine which tectonic zones diamond deposits gravitate towards.

2. Basic level. Is it possible to say that all countries without exception that produce a lot of gem-quality diamonds are among the rich?
Good level. In which countries do you think the contrasts between production volumes and the poverty of the majority of the population are most striking? Why do you think the standard of living is low in countries such as Angola, Congo (Kinshasa), Sierra Leone?
Creative level. Try to determine which developed countries can “help” poor developing countries in diamond mining (this branch of the mining industry is rightly considered one of the most capital-intensive)? Who do you think gets most of the profits?

3. Basic level. Are they similar? lists of countries, leading in diamond mining and production of artificial diamonds? Which countries appear on both lists?
Good level. Plot on the contour map (above) with bars (at the same scale as for jewelry diamonds) the production volumes of synthetic diamonds by the ten largest producers.
Creative level. Which of the following factors do you think most determines the location of the production of artificial diamonds: the need for diamonds, the presence of a production base for the production and cutting of natural diamonds, a large population, remoteness from the places where natural diamonds are mined?

4 (festive ).Basic level. Knowing the population of the Earth and the fact that the total number of men on the planet is approximately equal to the number of women, find out how many carats of natural jewelry diamonds are mined annually for every thousand inhabitants of our planet.
Good level. Complete the same task, calculating how many diamonds are mined annually per thousand female souls in each of the top ten countries.
Creative level. Determine how much natural jewelry diamonds need to be mined in our country in order to annually present every Russian woman with a diamond of at least one carat (conditionally assuming that diamonds will not be exported abroad).