The Republic of Sakha is a federal Russian republic. It had a population of 958,528 at the 2010 Census ethnic Yakuts and Russians. Comprising half the Far Eastern Federal District, it is the largest subnational governing body by area in the world at 3,083,523 square kilometers, its capital is the city of Yakutsk. It is known for its extreme and severe climate, with the lowest temperatures in the Northern Hemisphere being recorded in Verkhoyansk and Delyankir, regular winter averages being below −35 °C in Yakutsk; the hypercontinental tendencies result in warm summers for much of the republic. Borders: internal: Chukotka Autonomous Okrug, Magadan Oblast, Khabarovsk Krai, Amur Oblast, Zabaykalsky Krai, Irkutsk Oblast, Krasnoyarsk Krai. Water: Arctic Ocean. Highest point: Peak Pobeda, Mus-Khaya Mountain Peak Maximum N->S distance: 2,500 km Maximum E->W distance: 2,000 km Sakha stretches to the Henrietta Island in the far north and is washed by the Laptev and Eastern Siberian Seas of the Arctic Ocean.
These waters, the coldest and iciest of all seas in the Northern Hemisphere, are covered by ice for 9–10 months of the year. New Siberian Islands are a part of the republic's territory. After Nunavut was separated from Canada's Northwest Territories, Sakha became the largest subnational entity in the world, with an area of 3,083,523 square kilometers smaller than the territory of India. Sakha can be divided into three great vegetation belts. About 40% of Sakha lies above the Arctic circle and all of it is covered by permafrost which influences the region's ecology and limits forests in the southern region. Arctic and subarctic tundra define the middle region, where lichen and moss grow as great green carpets and are favorite pastures for reindeer. In the southern part of the tundra belt, scattered stands of dwarf Siberian pine and larch grow along the rivers. Below the tundra is the vast taiga forest region. Larch trees dominate in the north and stands of fir and pine begin to appear in the south.
Taiga forests cover about 47% of Sakha and 90% of the cover is larch. The Sakha Republic is the site of Pleistocene Park, a project directed at recreating Pleistocene tundra grasslands by stimulating the growth of grass with the introduction of animals which thrived in the region during the late Pleistocene — early Holocene period. Sakha Republic is the only subject of Russia. Sakha spans three time zones: Yakutsk Time Zone. Covers the republic's territory to the west of the Lena River as well as the territories of the districts located on both sides of the Lena River. Vladivostok Time Zone. Covers most of the republic's territory located between 140 ° E longitude. Districts: Oymyakonsky, Ust-Yansky, Verkhoyansky. Magadan Time Zone. Covers most of the republic's territory located east of 140°E longitude. Districts: Abyysky, Momsky, Srednekolymsky, Verkhnekolymsky. Navigable Lena River, as it moves northward, includes hundreds of small tributaries located in the Verkhoyansk Range. Other major rivers include: Vilyuy River Lena River tributary Olenyok River Aldan River Lena River tributary Kolyma River Indigirka River Alazeya River Amga River Aldan River tributary Olyokma River Lena River tributary Markha River Vilyuy River tributary Tyung River Vilyuy River tributary Maya River Aldan River tributary Anabar River Yana River Morkoka River Markha River tributary Uchur River Aldan River tributary Linde River Lena River tributary Nyuya River Lena River tributary Selennyakh River Indigirka River tributary There are over 800,000 lakes in the republic.
Major lakes and reservoirs include: Lake Mogotoyevo Lake Nedzheli Lake Nerpichye Vilyuyskoye Reservoir Sakha's greatest mountain range, the Verkhoyansk Range, runs parallel and east of the Lena River, forming a great arc that begins in the Sea of Okhotsk and ends in the Laptev Sea. The Chersky Range has the highest peak in Sakha, Peak Pobeda; the second highest peak is Peak Mus-Khaya reaching 3,011 m. The Stanovoi Range borders Sakha in the south; the Republic's extensive coastline contains a number of peninsulas. The soil contains large reserves of oil, coal, gold, tin and many others. Sakha p
The Udachnaya pipe is a diamond deposit in the Daldyn-Alakit kimberlite field in Sakha Republic, Russia. It is an open-pit mine, is located just outside the Arctic circle at 66°26′N 112°19′E. Udachnaya was discovered on 15 June 1955, just two days after the discovery of the diamond pipe Mir by Soviet geologist Vladimir Shchukin and his team, it is more than 600 metres deep. The nearby settlement of Udachny is named for the deposit; as of 2010, Udachnaya pipe is controlled by Russian diamond company Alrosa, which planned to halt open-pit mining in favor of underground mining in 2010. The mine has estimated reserves of 225.8 million carats of diamonds and an annual production capacity of 10.4 million carats. Mir mine Volcanic pipe Satellite photo of the Udachnaya pipe Alexeev, Sergey V. Drozdova. "The First Experience of Saline Drainage Waters Disposal from the Udachnaya Pipe Quarry into Permaforest". Institute of Arctic and Alpine Research, University of Colorado at Boulder
Diamond is a solid form of the element carbon with its atoms arranged in a crystal structure called diamond cubic. At room temperature and pressure, another solid form of carbon known as graphite is the chemically stable form, but diamond never converts to it. Diamond has the highest hardness and thermal conductivity of any natural material, properties that are utilized in major industrial applications such as cutting and polishing tools, they are the reason that diamond anvil cells can subject materials to pressures found deep in the Earth. Because the arrangement of atoms in diamond is rigid, few types of impurity can contaminate it. Small numbers of defects or impurities color diamond blue, brown, purple, orange or red. Diamond has high optical dispersion. Most natural diamonds have ages between 1 billion and 3.5 billion years. Most were formed at depths between 150 and 250 kilometers in the Earth's mantle, although a few have come from as deep as 800 kilometers. Under high pressure and temperature, carbon-containing fluids dissolved minerals and replaced them with diamonds.
Much more they were carried to the surface in volcanic eruptions and deposited in igneous rocks known as kimberlites and lamproites. Synthetic diamonds can be grown from high-purity carbon under high pressures and temperatures or from hydrocarbon gas by chemical vapor deposition. Imitation diamonds can be made out of materials such as cubic zirconia and silicon carbide. Natural and imitation diamonds are most distinguished using optical techniques or thermal conductivity measurements. Diamond is a solid form of pure carbon with its atoms arranged in a crystal. Solid carbon comes in different forms known as allotropes depending on the type of chemical bond; the two most common allotropes of pure carbon are graphite. In graphite the bonds are sp2 orbital hybrids and the atoms form in planes with each bound to three nearest neighbors 120 degrees apart. In diamond they are sp3 and the atoms form tetrahedra with each bound to four nearest neighbors. Tetrahedra are rigid, the bonds are strong, of all known substances diamond has the greatest number of atoms per unit volume, why it is both the hardest and the least compressible.
It has a high density, ranging from 3150 to 3530 kilograms per cubic metre in natural diamonds and 3520 kg/m³ in pure diamond. In graphite, the bonds between nearest neighbors are stronger but the bonds between planes are weak, so the planes can slip past each other. Thus, graphite is much softer than diamond. However, the stronger bonds make graphite less flammable. Diamonds have been adapted for many uses because of the material's exceptional physical characteristics. Most notable are its extreme hardness and thermal conductivity, as well as wide bandgap and high optical dispersion. Diamond's ignition point is 720 -- 800 °C in 850 -- 1000 °C in air; the equilibrium pressure and temperature conditions for a transition between graphite and diamond is well established theoretically and experimentally. The pressure changes linearly between 1.7 GPa at 0 K and 12 GPa at 5000 K. However, the phases have a wide region about this line where they can coexist. At normal temperature and pressure, 20 °C and 1 standard atmosphere, the stable phase of carbon is graphite, but diamond is metastable and its rate of conversion to graphite is negligible.
However, at temperatures above about 4500 K, diamond converts to graphite. Rapid conversion of graphite to diamond requires pressures well above the equilibrium line: at 2000 K, a pressure of 35 GPa is needed. Above the triple point, the melting point of diamond increases with increasing pressure. At high pressures and germanium have a BC8 body-centered cubic crystal structure, a similar structure is predicted for carbon at high pressures. At 0 K, the transition is predicted to occur at 1100 GPa; the most common crystal structure of diamond is called diamond cubic. It is formed of unit cells stacked together. Although there are 18 atoms in the figure, each corner atom is shared by eight unit cells and each atom in the center of a face is shared by two, so there are a total of eight atoms per unit cell; each side of the unit cell is 3.57 angstroms in length. A diamond cubic lattice can be thought of as two interpenetrating face-centered cubic lattices with one displaced by 1/4 of the diagonal along a cubic cell, or as one lattice with two atoms associated with each lattice point.
Looked at from a <1 1 1> crystallographic direction, it is formed of layers stacked in a repeating ABCABC... pattern. Diamonds can form an ABAB... structure, known as hexagonal diamond or lonsdaleite, but this is far less common and is formed under different conditions from cubic carbon. Diamonds occur most as euhedral or rounded octahedra and twinned octahedra known as macles; as diamond's crystal structure has a cubic arrangement of the atoms, they have many facets that belong to a cube, rhombicosidodecahedron, tetrakis hexahedron or disdyakis dodecahedron. The crystals can be elongated. Diamonds are found coated in nyf, an opaque gum-like skin; some diamonds have opaque fibers. They are referred to as opaque if the fibers
South African Border War
The South African Border War known as the Namibian War of Independence, sometimes denoted in South Africa as the Angolan Bush War, was a asymmetric conflict that occurred in Namibia and Angola from 26 August 1966 to 21 March 1990. It was fought between the South African Defence Force and the People's Liberation Army of Namibia, an armed wing of the South West African People's Organisation; the South African Border War resulted in some of the largest battles on the African continent since World War II and was intertwined with the Angolan Civil War. Following several decades of unsuccessful petitioning through the United Nations and the International Court of Justice for Namibian independence, SWAPO formed the PLAN in 1962 with material assistance from the Soviet Union, the People's Republic of China, sympathetic African states such as Tanzania and Algeria. Fighting broke out between PLAN and the South African authorities in August 1966. Between 1975 and 1988 the SADF staged massive conventional raids into Angola and Zambia to eliminate PLAN's forward operating bases.
It deployed specialist counter-insurgency units such as Koevoet and 32 Battalion trained to carry out external reconnaissance and track guerrilla movements. South African tactics became aggressive as the conflict progressed; the SADF's incursions produced Angolan casualties and resulted in severe collateral damage to economic installations regarded as vital to the Angolan economy. Ostensibly to stop these raids, but to disrupt the growing alliance between the SADF and the National Union for the Total Independence for Angola, which the former was arming with captured PLAN equipment, the Soviet Union backed the People's Armed Forces of Liberation of Angola through a large contingent of military advisers and up to four billion dollars' worth of modern defence technology in the 1980s. Beginning in 1984, regular Angolan units under Soviet command were confident enough to confront the SADF, their positions were bolstered by thousands of Cuban troops. The state of war between South Africa and Angola ended with the short-lived Lusaka Accords, but resumed in August 1985 as both PLAN and UNITA took advantage of the ceasefire to intensify their own guerrilla activity, leading to a renewed phase of FAPLA combat operations culminating in the Battle of Cuito Cuanavale.
The South African Border War was ended by the Tripartite Accord, mediated by the United States, which committed to a withdrawal of Cuban and South African military personnel from Angola and South West Africa, respectively. PLAN launched its final guerrilla campaign in late March 1989. South West Africa received formal independence as the Republic of Namibia a year on 21 March 1990. Despite being fought in neighbouring states, the South African Border War had a phenomenal cultural and political impact on South African society; the country's apartheid government devoted considerable effort towards presenting the war as part of a containment programme against regional Soviet expansionism and used it to stoke public anti-communist sentiment. It remains an integral theme in contemporary South African literature at large and Afrikaans-language works in particular, having given rise to a unique genre known as grensliteratuur. Various names have been applied to the undeclared conflict waged by South Africa in Angola and Namibia from the mid 1960s to the late 1980s.
The term "South African Border War" has denoted the military campaign launched by the People's Liberation Army of Namibia, which took the form of sabotage and rural insurgency, as well as the external raids launched by South African troops on suspected PLAN bases inside Angola or Zambia, sometimes involving major conventional warfare against the People's Armed Forces of Liberation of Angola and its Cuban allies. The strategic situation was further complicated by the fact that South Africa occupied large swathes of Angola for extended periods in support of the National Union for the Total Independence of Angola, making the "Border War" an inseparable conflict from the parallel Angolan Civil War."Border War" entered public discourse in South Africa during the late 1970s, was adopted thereafter by the country's ruling National Party. Due to the covert nature of most South African Defence Force operations inside Angola, the term was favoured as a means of omitting any reference to clashes on foreign soil.
Where tactical aspects of various engagements were discussed, military historians identified the conflict as the "bush war". The South West African People's Organisation has described the South African Border War as the Namibian War of National Liberation and the Namibian Liberation Struggle. In the Namibian context it is commonly referred to as the Namibian War of Independence. However, these terms have been criticised for ignoring the wider regional implications of the war and the fact that PLAN was based in, did most of its fighting from, countries other than Namibia. Namibia was governed as German South West Africa, a colony of the German Empire, until World War I, when it was invaded and occupied by Allied forces under General Louis Botha. Following the Armistice of 11 November 1918, a mandate system was imposed by the League of Nations to govern African and Asian territories held by Germany and the Ottoman Empire prior to the war; the mandate system was formed as a compromise between those who advocated an Allied annexation of former German and Turkish territories, another proposition put forward by those who wished to grant them to an international trusteeship until they could govern themsel
Kimberlite is an igneous rock, which sometimes contains diamonds. It is named after the town of Kimberley in South Africa, where the discovery of an 83.5-carat diamond called the Star of South Africa in 1869 spawned a diamond rush and the digging of the open-pit mine called the Big Hole. The term kimberlite has been applied to olivine lamproites as Kimberlite II, however this has been in error. Kimberlite occurs in the Earth's crust in vertical structures known as kimberlite pipes, as well as igneous dykes. Kimberlite occurs as horizontal sills. Kimberlite pipes are the most important source of mined diamonds today; the consensus on kimberlites is. Formation occurs at depths between 150 and 450 kilometres from anomalously enriched exotic mantle compositions, they are erupted and violently with considerable carbon dioxide and other volatile components, it is this depth of melting and generation that makes kimberlites prone to hosting diamond xenocrysts. Despite its relative rarity, kimberlite has attracted attention because it serves as a carrier of diamonds and garnet peridotite mantle xenoliths to the Earth's surface.
Its probable derivation from depths greater than any other igneous rock type, the extreme magma composition that it reflects in terms of low silica content and high levels of incompatible trace-element enrichment make an understanding of kimberlite petrogenesis important. In this regard, the study of kimberlite has the potential to provide information about the composition of the deep mantle and melting processes occurring at or near the interface between the cratonic continental lithosphere and the underlying convecting asthenospheric mantle. Many kimberlite structures are emplaced as carrot-shaped, vertical intrusions termed "pipes"; this classic carrot shape is formed due to a complex intrusive process of kimberlitic magma, which inherits a large proportion of CO2 in the system, which produces a deep explosive boiling stage that causes a significant amount of vertical flaring. Kimberlite classification is based on the recognition of differing rock facies; these differing facies are associated with a particular style of magmatic activity, namely crater and hypabyssal rocks.
The morphology of kimberlite pipes and their classical carrot shape is the result of explosive diatreme volcanism from deep mantle-derived sources. These volcanic explosions produce vertical columns of rock; the morphology of kimberlite pipes is varied, but includes a sheeted dyke complex of tabular, vertically dipping feeder dykes in the root of the pipe, which extends down to the mantle. Within 1.5–2 km of the surface, the pressured magma explodes upwards and expands to form a conical to cylindrical diatreme, which erupts to the surface. The surface expression is preserved but is similar to a maar volcano. Kimberlite dikes and sills can be thin, while pipes range in diameter from about 75 meters to 1.5 kilometers. Two Jurassic kimberlite dikes exist in Pennsylvania. One, the Gates-Adah Dike, outcrops on the Monongahela River on the border of Fayette and Greene Counties; the other, the Dixonville-Tanoma Dike in central Indiana County, does not outcrop at the surface and was discovered by miners.
Aged kimberlite is found in several locations in New York. Both the location and origin of kimberlitic magmas are subjects of contention, their extreme enrichment and geochemistry have led to a large amount of speculation about their origin, with models placing their source within the sub-continental lithospheric mantle or as deep as the transition zone. The mechanism of enrichment has been the topic of interest with models including partial melting, assimilation of subducted sediment or derivation from a primary magma source. Kimberlites have been classified into two distinct varieties, termed "basaltic" and "micaceous" based on petrographic observations; this was revised by C. B. Smith, who renamed these divisions "group I" and "group II" based on the isotopic affinities of these rocks using the Nd, Sr and Pb systems. Roger Mitchell proposed that these group I and II kimberlites display such distinct differences, that they may not be as related as once thought, he showed that group II kimberlites show closer affinities to lamproites than they do to group I kimberlites.
Hence, he reclassified. Group-I kimberlites are of CO2-rich ultramafic potassic igneous rocks dominated by primary forsteritic olivine and carbonate minerals, with a trace-mineral assemblage of magnesian ilmenite, chromium pyrope, almandine-pyrope, chromium diopside, enstatite and of Ti-poor chromite. Group I kimberlites exhibit a distinctive inequigranular texture caused by macrocrystic to megacrystic phenocrysts of olivine, chromian diopside, magnesian ilmenite, phlogopite, in a fine- to medium-grained groundmass; the groundmass mineralogy, which more resembles a true composition of the igneous rock, is dominated by carbonate and significant amounts of forsteritic olivine, with lesser amounts of pyrope garnet, Cr-diopside, magnesian ilmenite, spinel. Olivine lamproites were called group II kimberlite or orangeite in response to the mistaken belief that they only occurred in South Africa, their occurrence and petrology, are identical globally and should not be erroneously referred to as kimberlite.
Olivine lamproites are ultrapotassic. The distinctive characteristic of olivine lamproi
Siberia is an extensive geographical region spanning much of Eurasia and North Asia. Siberia has been a part of modern Russia since the 17th century; the territory of Siberia extends eastwards from the Ural Mountains to the watershed between the Pacific and Arctic drainage basins. The Yenisei River conditionally divides Siberia into two parts and Eastern. Siberia stretches southwards from the Arctic Ocean to the hills of north-central Kazakhstan and to the national borders of Mongolia and China. With an area of 13.1 million square kilometres, Siberia accounts for 77% of Russia's land area, but it is home to 36 million people—27% of the country's population. This is equivalent to an average population density of about 3 inhabitants per square kilometre, making Siberia one of the most sparsely populated regions on Earth. If it were a country by itself, it would still be the largest country in area, but in population it would be the world's 35th-largest and Asia's 14th-largest. Worldwide, Siberia is well known for its long, harsh winters, with a January average of −25 °C, as well as its extensive history of use by Russian and Soviet administrations as a place for prisons, labor camps, exile.
The origin of the name is unknown. Some sources say that "Siberia" originates from the Siberian Tatar word for "sleeping land". Another account sees the name as the ancient tribal ethnonym of the Sirtya, an ethnic group which spoke a Paleosiberian language; the Sirtya people were assimilated into the Siberian Tatars. The modern usage of the name was recorded in the Russian language after the Empire's conquest of the Siberian Khanate. A further variant claims; the Polish historian Chyliczkowski has proposed that the name derives from the proto-Slavic word for "north", but Anatole Baikaloff has dismissed this explanation. He said that the neighbouring Chinese and Mongolians, who have similar names for the region, would not have known Russian, he suggests that the name might be a combination of two words with Turkic origin, "su" and "bir". The region has paleontological significance, as it contains bodies of prehistoric animals from the Pleistocene Epoch, preserved in ice or in permafrost. Specimens of Goldfuss cave lion cubs and another woolly mammoth from Oymyakon, a woolly rhinoceros from the Kolyma River, bison and horses from Yukagir have been found.
The Siberian Traps were formed by one of the largest-known volcanic events of the last 500 million years of Earth's geological history. Their activity continued for a million years and some scientists consider it a possible cause of the "Great Dying" about 250 million years ago, – estimated to have killed 90% of species existing at the time. At least three species of human lived in Southern Siberia around 40,000 years ago: H. sapiens, H. neanderthalensis, the Denisovans. In 2010 DNA evidence identified the last as a separate species. Siberia was inhabited by different groups of nomads such as the Enets, the Nenets, the Huns, the Scythians and the Uyghurs; the Khan of Sibir in the vicinity of modern Tobolsk was known as a prominent figure who endorsed Kubrat as Khagan of Old Great Bulgaria in 630. The Mongols conquered a large part of this area early in the 13th century. With the breakup of the Golden Horde, the autonomous Khanate of Sibir was established in the late 15th century. Turkic-speaking Yakut migrated north from the Lake Baikal region under pressure from the Mongol tribes during the 13th to 15th century.
Siberia remained a sparsely populated area. Historian John F. Richards wrote: "... it is doubtful that the total early modern Siberian population exceeded 300,000 persons."The growing power of Russia in the West began to undermine the Siberian Khanate in the 16th century. First, groups of traders and Cossacks began to enter the area; the Russian Army was directed to establish forts farther and farther east to protect new settlers from European Russia. Towns such as Mangazeya, Tara and Tobolsk were developed, the last being declared the capital of Siberia. At this time, Sibir was the name of a fortress at Qashlik, near Tobolsk. Gerardus Mercator, in a map published in 1595, marks Sibier both as the name of a settlement and of the surrounding territory along a left tributary of the Ob. Other sources contend that the Xibe, an indigenous Tungusic people, offered fierce resistance to Russian expansion beyond the Urals; some suggest. By the mid-17th century, Russia had established areas of control; some 230,000 Russians had settled in Siberia by 1709.
Siberia was a destination for sending exiles. The first great modern change in Siberia was the Trans-Siberian Railway, constructed during 1891–1916, it linked Siberia more to the industrialising Russia of Nicholas II. Around seven million people moved to Siberia from European Russia between 1801 and 1914. From 1859 to 1917, more than half a million people migrated to the Russian Far East. Siberia has extensive natural resources. During the 20th century, large-scale exploitation of these was developed, industrial towns cropped up throughout the region. At 7:15 a.m. on 30 June 1908, millions of trees were felled near the Podkamennaya Tunguska River in central Siberia in the Tunguska Event. Most scientists believe this resulted from the air burst of a comet. Though no crater has been found, the landscape in the area still bears the scars of this event. In the early decades of the Soviet Union (
Alrosa is a Russian group of diamond mining companies that specialize in exploration, mining and sale of diamonds. The company leads the world in diamond mining by volume. Mining takes place in Western Yakutia, the Arkhangelsk region, Africa. Alrosa is Russia's leading diamond company accounting for 95% of country's diamond production and 27% of the global diamond extraction; the company's headquarters are located in Moscow. The history of Alrosa dates back to 1954, when the first primary deposit of diamonds in the Soviet Union, the kimberlite pipe Zarnitsa, was found. In 1955 the Mir kimberlite pipe and the Udachnaya pipe were discovered. A total of fifteen primary diamond sources were found in 1955. In 1957, a decision was made to begin mining and production operations on alluvial and ore deposits in Yakutia. To manage the facilities construction and subsequent operations, the Yakutalmaz group of companies was established with headquarters in Mirny; the first commercial-grade diamonds were recovered the same year.
Two years the Soviet Union sold the first shipment of diamonds on the world market. For the most part during the Soviet period, the diamond mining industry developed on the basis of the Mir open-pit mine and adjacent alluvial deposits. In those years its main open-pit mines, processing plants and related energy generating facilities were put into operation. In 1960, the Djomolungma and Chimyan was discovered, in 1969, the International kimberlite pipe. In 1963, the first sales contracts between the USSR and De Beers group were signed. In 2009 this cooperation was brought to an end as contrary to European Union competition laws in compliance with a decision of the European Commission. Now Alrosa independently distributes its rough diamond production on the world market. Through 1980, rapid development of primary deposits continued in Aikhal township on the basis of the Jubilee pipe and in Udachny town. Today the Udachny open-pit mine is one of the largest open-pit mines in the world. Alrosa closed joint-stock company was set up according to Presidential Decree №158C of the President of Russia "On the Establishment of the Almazy Rossii-Sakha Joint Stock Company" signed on 19 February 1992, based on NPO Yakutalmaz, a former USSR state-owned diamond mining company.
In 2011, Alrosa was reorganized as an open joint-stock company with free float of Alrosa's shares on financial markets. In July 2007, Verkhne-Munskoye diamond field in Yakutia was discovered with an estimated value of about $3.5 billion. In August 2009, during the recent financial crisis, Prime Minister Vladimir Putin announced the Russian government, via Gokhran, would buy $1 billion in uncut diamonds from Alrosa; this was to support the Russian diamond mining industry while avoiding saturation in the global diamond market and thus further depression of diamond prices. The diamond mining industry is critical to the Yakutia economy. On 28 October 2013, the company carried out the IPO; the Russian government and the Republic of Sakha sold a combined 14% stake, while Alrosa offered about 2% in treasury stock. U. S. investors were the biggest buyers of the shares, purchasing up to 60% of the stake, 24% got European investors, Russian investors accounted for about 14%. Investment funds Oppenheimer Funds Inc. and Lazard Ltd. took part in the IPO and bought over 2% of the stake.
Alrosa raised $1.3 billion in share sales. In 2016, Alrosa was ranked as being among the 12th best of 92 oil and mining companies on indigenous rights in the Arctic. In 2017, ALROSA was ranked among the top three in the environmental responsibility rating of the Russian mining and smelting companies; the rating was developed by the World Wildlife Fund, United Nations Development Programme, Global Environment Facility, the Ministry of Natural Resources and Environment of the Russian Federation. In June 2017, Memorandum of Cooperation between PJSC ALROSA and Gem & Jewelry Export Promotion Council was signed in the scope of India-Russia Summit with the participation of the Russian President Vladimir Putin and Indian Prime Minister Narendra Modi. In June 2017, ALROSA entered Top-5 of companies with sustainable development, according to "Polar Index". “Polar Index” is the first and only specialized rating in Russia of companies whose geography of activities affects the Arctic zone of Russia. According to the results of the research conducted by PwC in 2017, ALROSA is an absolute leader in terms of investments in social programs directing to social spending on average 2.8% of its revenue.
In January 2018, ALROSA entered the list of Top-10 companies with the highest transparency index in the framework of the study "Transparency in Corporate Reporting", prepared by Transparency International - Russia. ALROSA is the sector's largest public diamond mining company, its public float is 34%, with 33% owned by the Russian Federation. The Company’s market capitalization was RUB 553 billion in 2017. On 13 March 2017, Sergey Ivanov was elected as the president of ALROSA. Since 11 January 2018, senior leadership position was renamed into "chief executive officer - chairman of the executive committee"; the main production facilities are concentrated in Western Yakutia and the Arkhangelsk region. In total Alrosa is developing 27 fields; the Company has a diversified production base consisting of 16 alluvial deposits. Primary deposits are developed both open-pit, alluvial operations and underground mining."Mining". Alrosa. Retrieved 30 August 2018. On the territory of the Republic of Sakha Alrosa has four mining and processing divisions - Mirny, Udachny, Nyurba.
The rest of deposits are developing through subsidia