146-477: The Marange diamond fields are an area of widespread small-scale diamond production in Chiadzwa , Mutare District , Zimbabwe . 'Although estimates of the reserves contained in this area vary wildly, some have suggested that it could be home to one of the world's richest diamond deposits'. The hugely prolific fields are regarded by some experts as the world's biggest (in carats, not by value) diamond find in more than
292-607: A subduction zone . Zimbabwe National Army The Zimbabwe National Army ( ZNA ) is the primary branch of the Zimbabwe Defence Forces responsible for land-oriented military operations . It is the largest service branch under the Zimbabwean Joint Operations Command (JOC). The modern army has its roots in the Rhodesian Army , which was raised between 1963 and 1964 after the breakup of
438-486: A Christie's auction. In May 2009, a 7.03-carat (1.406 g) blue diamond fetched the highest price per carat ever paid for a diamond when it was sold at auction for 10.5 million Swiss francs (6.97 million euros, or US$ 9.5 million at the time). That record was, however, beaten the same year: a 5-carat (1.0 g) vivid pink diamond was sold for US$ 10.8 million in Hong Kong on December 1, 2009. Clarity
584-634: A century. Production from Marange is controversial due to ongoing legal wrangles and government crackdowns on illegal miners and allegations of forced labour. In terms of carats produced, the Marange field is the largest diamond-producing project in the world, estimated to have produced 16.9 million carats in 2013, or 13% of global rough diamond supply. Marange is estimated to have produced 12 million carats in 2012, 8.7 million carats in 2011, and 8.2 million carats in 2010. While some diamond mines produce rough valued at over $ 1000 per carat, average production at Marange
730-453: A cigarette lighter, but house fires and blow torches are hot enough. Jewelers must be careful when molding the metal in a diamond ring. Diamond powder of an appropriate grain size (around 50 microns) burns with a shower of sparks after ignition from a flame. Consequently, pyrotechnic compositions based on synthetic diamond powder can be prepared. The resulting sparks are of the usual red-orange color, comparable to charcoal, but show
876-603: A clampdown on smuggling of diamonds from Zimbabwe. In December 2008, the Kimberley Process Civil Society Coalition , representing non-governmental organisations which participate in KP, called for Zimbabwe's suspension. In a statement issued by Global Witness , the coalition said the Kimberley Process (should) suspend Zimbabwe from the rough diamond certification scheme, in light of recent violence used by
1022-623: A common Marxist ideology of scientific socialism. The South Africa-backed RENAMO professed to be an anti-communist movement, as did Jonas Savimbi's UNITA movement, which was fighting against the Marxist MPLA government of Angola. There was thus an ideological alliance of the Maputo – Harare – Luanda axis, with support for these governments from the Soviet Union. The fact that the United States of America
1168-542: A contingent of Zimbabwe Defence Forces and Zimbabwe Republic Police personnel, reportedly including the Commando Anti-Terrorism Unit, were deployed to Equatorial Guinea to provide security and support during the Africa Cup of Nations tournament. The deployment followed a bi-lateral agreement between the two countries' heads of state and was code named Restoring African Pride. Equatorial Guinea had agreed to host
1314-727: A continuum with carbonatites , but the latter have too much oxygen for carbon to exist in a pure form. Instead, it is locked up in the mineral calcite ( Ca C O 3 ). All three of the diamond-bearing rocks (kimberlite, lamproite and lamprophyre) lack certain minerals ( melilite and kalsilite ) that are incompatible with diamond formation. In kimberlite , olivine is large and conspicuous, while lamproite has Ti- phlogopite and lamprophyre has biotite and amphibole . They are all derived from magma types that erupt rapidly from small amounts of melt, are rich in volatiles and magnesium oxide , and are less oxidizing than more common mantle melts such as basalt . These characteristics allow
1460-452: A diamond to fluoresce. Diamonds can fluoresce in a variety of colors including blue (most common), orange, yellow, white, green and very rarely red and purple. Although the causes are not well understood, variations in the atomic structure, such as the number of nitrogen atoms present are thought to contribute to the phenomenon. Diamonds can be identified by their high thermal conductivity (900– 2320 W·m ·K ). Their high refractive index
1606-481: A dramatic intervention in domestic politics to force the resignation of long-time President Robert Mugabe. The operation was stated to have the objective of removing criminal elements that had surrounded the President, 'resulting in anxiety and despondency among the public'. This referred to a number of politicians from the ruling ZANU-PF party that supported President Mugabe's wife and seemed intent on manoeuvering her into
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#17328510341741752-710: A first light take-off for Gorongosa on the morning of 28 August. Although the RENAMO elements captured at Katiyo had given a grid reference for Cassa Banana, further intelligence had cast some doubt as to which of the several RENAMO bases scattered on all sides of the Gorongosa Mountains was the actual headquarters of RENAMO. It was because of this uncertainty that the Fireforce was divided into three sections each with one helicopter gunship, two transport helicopters and two transport aircraft with paratroopers. Each Fireforce section
1898-475: A gemstone. Because it can only be scratched by other diamonds, it maintains its polish extremely well. Unlike many other gems, it is well-suited to daily wear because of its resistance to scratching—perhaps contributing to its popularity as the preferred gem in engagement or wedding rings , which are often worn every day. The hardest natural diamonds mostly originate from the Copeton and Bingara fields located in
2044-560: A legitimate diamond export. In July 2010 the Kimberley Process Certification Scheme agreed that diamonds from Marange could be sold on the international market after a report from the Scheme's monitor a month earlier described diamonds mined from the fields as conflict-free . The New York Times reported on Monday, 5 December 2011 that Global Witness had withdrawn from the Kimberley Process coalition, saying that it felt
2190-475: A metallic fluid. The extreme conditions required for this to occur are present in the ice giants Neptune and Uranus . Both planets are made up of approximately 10 percent carbon and could hypothetically contain oceans of liquid carbon. Since large quantities of metallic fluid can affect the magnetic field, this could serve as an explanation as to why the geographic and magnetic poles of the two planets are unaligned. The most common crystal structure of diamond
2336-451: A month... Our superiors back in the barracks are fully aware of what we are doing, and they let us continue because they benefit from this illegal mining of the diamonds. Every week, we surrender a substantial amount of the mineral to them. The government launched police crackdowns against illegal miners and smugglers several times since December 2006. In November 2008 the Air Force of Zimbabwe
2482-403: A pale blue flame, and continues to burn after the source of heat is removed. By contrast, in air the combustion will cease as soon as the heat is removed because the oxygen is diluted with nitrogen. A clear, flawless, transparent diamond is completely converted to carbon dioxide; any impurities will be left as ash. Heat generated from cutting a diamond will not ignite the diamond, and neither will
2628-405: A predetermined Initial Point (IP), were then talked on to the target, and the raid on Cassa Banana began. The aircraft attacked the target, knocking out several Anti-Aircraft gun positions. Two helicopter gunships continued to hit suspected strategic positions and managed to flash out several pockets of resistance. A third helicopter was directing the dropping of the first wave of paratroopers. When
2774-413: A riverbed. Look like tumbled and abraded coarse chips of broken beer bottles with colours ranging from dark brown to black to darkish green. Most surfaces are matt (sic) and dulled with rounded corners and edges. Broken surfaces display 'metallic-like' lustre." The report also contains photographs showing Marange diamonds in various stages of processing, so they can be recognized if they are mixed in with
2920-597: A signal troop, and engineers. Raised by colonial authorities to suppress further uprisings after the Second Matabele War , it included a "Western division" and an "Eastern division" staffed by European volunteers. Field outings were conducted in concert with the British South Africa Police (BSAP). In the 1890s, the nature of this force changed following the outbreak of the Second Boer War . In 1899,
3066-492: A string of other smaller bases along the Gorongosa Mountains, which were considered as part of the main base. This raised the total estimated strength in the area to 1,000 elements. During the night of 27 August 1985, three Zimbabwe infantry battalions were established in their Form Up Points (FUP) with the help of the SAS and Commando elements. At Chimoio a Fireforce was being given final briefing, and five AFZ planes were given orders for
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#17328510341743212-616: A torture camp in the Marange diamond fields; methods include severe beatings, sexual assault and dog mauling according to alleged victims. Zimbabwe is a participant in the Kimberley Process (KP), that regulates trade in diamonds, although by June 2007 the KP annual plenary stated that it noted with concern the continuing challenges to KP implementation in Zimbabwe and recommended further monitoring of developments and concerted actions in that respect. The World Diamond Council has called for
3358-542: A total of 29 battalions. The brigade support units were composed almost entirely of specialists of the former Rhodesian Army, while unintegrated battalions of the Rhodesian African Rifles were assigned to the 1st, 3rd and 4th Brigades. A 5th was formed in 1981 and deployed primarily against ex-ZIPRA dissidents until 1987. The unit was later implicated in an extrajudicial purge of suspected dissidents and their supporters, known as Gukurahundi . From August 2021,
3504-463: A transition between graphite and diamond are well established theoretically and experimentally. The equilibrium pressure varies linearly with temperature, between 1.7 GPa at 0 K and 12 GPa at 5000 K (the diamond/graphite/liquid triple point ). However, the phases have a wide region about this line where they can coexist. At standard temperature and pressure , 20 °C (293 K) and 1 standard atmosphere (0.10 MPa),
3650-467: A very linear trajectory which is explained by their high density. Diamond also reacts with fluorine gas above about 700 °C (1,292 °F). Diamond has a wide band gap of 5.5 eV corresponding to the deep ultraviolet wavelength of 225 nanometers. This means that pure diamond should transmit visible light and appear as a clear colorless crystal. Colors in diamond originate from lattice defects and impurities. The diamond crystal lattice
3796-421: A vested interest in chaos. By late 2008, mining was being carried out by soldiers , using local villagers for forced labour . The soldiers occasionally pay the villagers with diamonds and surrender much of the produce to their senior officers. According to one soldier interviewed by IRIN : As a soldier, just like most people in this country, I am poorly paid and my salary can hardly see me through three days of
3942-425: A volcanic rock. There are many theories for its origin, including formation in a star, but no consensus. Diamond is the hardest material on the qualitative Mohs scale . To conduct the quantitative Vickers hardness test , samples of materials are struck with a pyramid of standardized dimensions using a known force – a diamond crystal is used for the pyramid to permit a wide range of materials to be tested. From
4088-554: Is Lt. Gen. Anselem Sanyatwe . In 2011, Harare continued to maintain a statutory strength of 40,000 active personnel; actual numbers hover closer to 30,000. ZNA reserves claim another 21,800, putting the combined component strength total at approximately 51,800. The origins of the Zimbabwe National Army lie in the formation of the Southern Rhodesia Volunteers in 1898, a mounted corps supported by bicycles,
4234-467: Is metastable and converts to it at a negligible rate under those conditions. Diamond has the highest hardness and thermal conductivity of any natural material, properties that are used in major industrial applications such as cutting and polishing tools. They are also the reason that diamond anvil cells can subject materials to pressures found deep in the Earth. Because the arrangement of atoms in diamond
4380-449: Is 0.01% for nickel and even less for cobalt. Virtually any element can be introduced to diamond by ion implantation. Nitrogen is by far the most common impurity found in gem diamonds and is responsible for the yellow and brown color in diamonds. Boron is responsible for the blue color. Color in diamond has two additional sources: irradiation (usually by alpha particles), that causes the color in green diamonds, and plastic deformation of
4526-411: Is a solid form of the element carbon with its atoms arranged in a crystal structure called diamond cubic . Diamond as a form of carbon is a tasteless, odourless, strong, brittle solid, colourless in pure form, a poor conductor of electricity, and insoluble in water. Another solid form of carbon known as graphite is the chemically stable form of carbon at room temperature and pressure , but diamond
Marange diamond fields - Misplaced Pages Continue
4672-415: 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 diamond and graphite . In graphite, the bonds are sp orbital hybrids and the atoms form in planes, with each bound to three nearest neighbors, 120 degrees apart. In diamond, they are sp and
4818-420: Is aided by isotopic dating and modeling of the geological history. Then surveyors must go to the area and collect samples, looking for kimberlite fragments or indicator minerals . The latter have compositions that reflect the conditions where diamonds form, such as extreme melt depletion or high pressures in eclogites . However, indicator minerals can be misleading; a better approach is geothermobarometry , where
4964-723: Is also indicative, but other materials have similar refractivity. Diamonds are extremely rare, with concentrations of at most parts per billion in source rock. Before the 20th century, most diamonds were found in alluvial deposits . Loose diamonds are also found along existing and ancient shorelines , where they tend to accumulate because of their size and density. Rarely, they have been found in glacial till (notably in Wisconsin and Indiana ), but these deposits are not of commercial quality. These types of deposit were derived from localized igneous intrusions through weathering and transport by wind or water . Most diamonds come from
5110-405: Is another mechanical property toughness , which is a material's ability to resist breakage from forceful impact. The toughness of natural diamond has been measured as 50–65 MPa ·m . This value is good compared to other ceramic materials, but poor compared to most engineering materials such as engineering alloys, which typically exhibit toughness over 80 MPa·m . As with any material,
5256-414: Is called diamond cubic . It is formed of unit cells (see the figure) 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. The length of each side of the unit cell is denoted by a and is 3.567 angstroms . The nearest neighbor distance in
5402-426: Is estimated at under $ 50 per carat. From the early 1980s, De Beers held an Exclusive Prospecting Order (EPO) over Marange via their subsidiary Kimberlitic Searches Ltd. Their EPO expired in 2006 and exploration rights were taken up by British-registered African Consolidated Resources . Production from Marange is controversial due to ongoing legal wrangles and government crackdowns on illegal miners. In December 2006,
5548-402: Is exceptionally strong, and only atoms of nitrogen , boron , and hydrogen can be introduced into diamond during the growth at significant concentrations (up to atomic percents). Transition metals nickel and cobalt , which are commonly used for growth of synthetic diamond by high-pressure high-temperature techniques, have been detected in diamond as individual atoms; the maximum concentration
5694-574: Is extremely rigid, few types of impurity can contaminate it (two exceptions are boron and nitrogen ). Small numbers of defects or impurities (about one per million of lattice atoms) can color a diamond blue (boron), yellow (nitrogen), brown (defects), green (radiation exposure), purple, pink, orange, or red. Diamond also has a very high refractive index and a relatively 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 kilometres (93 and 155 mi) in
5840-419: Is formed of layers stacked in a repeating ABCABC ... pattern. Diamonds can also form an ABAB ... structure, which is known as hexagonal diamond or lonsdaleite , but this is far less common and is formed under different conditions from cubic carbon. Diamonds occur most often as euhedral or rounded octahedra and twinned octahedra known as macles . As diamond's crystal structure has a cubic arrangement of
5986-412: Is higher for flawless, pure crystals oriented to the <111> direction (along the longest diagonal of the cubic diamond lattice). Therefore, whereas it might be possible to scratch some diamonds with other materials, such as boron nitride , the hardest diamonds can only be scratched by other diamonds and nanocrystalline diamond aggregates . The hardness of diamond contributes to its suitability as
Marange diamond fields - Misplaced Pages Continue
6132-404: Is hybrid rock with a chaotic mixture of small minerals and rock fragments ( clasts ) up to the size of watermelons. They are a mixture of xenocrysts and xenoliths (minerals and rocks carried up from the lower crust and mantle), pieces of surface rock, altered minerals such as serpentine , and new minerals that crystallized during the eruption. The texture varies with depth. The composition forms
6278-647: Is in the form of micro/nanoscale wires or needles (~100–300 nanometers in diameter, micrometers long), they can be elastically stretched by as much as 9–10 percent tensile strain without failure, with a maximum local tensile stress of about 89–98 GPa , very close to the theoretical limit for this material. Other specialized applications also exist or are being developed, including use as semiconductors : some blue diamonds are natural semiconductors, in contrast to most diamonds, which are excellent electrical insulators . The conductivity and blue color originate from boron impurity. Boron substitutes for carbon atoms in
6424-477: Is one of the 4C's (color, clarity, cut and carat weight) that helps in identifying the quality of diamonds. The Gemological Institute of America (GIA) developed 11 clarity scales to decide the quality of a diamond for its sale value. The GIA clarity scale spans from Flawless (FL) to included (I) having internally flawless (IF), very, very slightly included (VVS), very slightly included (VS) and slightly included (SI) in between. Impurities in natural diamonds are due to
6570-797: Is partially oxidized. The oxidized surface can be reduced by heat treatment under hydrogen flow. That is to say, this heat treatment partially removes oxygen-containing functional groups. But diamonds (sp C) are unstable against high temperature (above about 400 °C (752 °F)) under atmospheric pressure. The structure gradually changes into sp C above this temperature. Thus, diamonds should be reduced below this temperature. At room temperature, diamonds do not react with any chemical reagents including strong acids and bases. In an atmosphere of pure oxygen, diamond has an ignition point that ranges from 690 °C (1,274 °F) to 840 °C (1,540 °F); smaller crystals tend to burn more easily. It increases in temperature from red to white heat and burns with
6716-765: Is possible to treat regular diamonds under a combination of high pressure and high temperature to produce diamonds that are harder than the diamonds used in hardness gauges. Diamonds cut glass, but this does not positively identify a diamond because other materials, such as quartz, also lie above glass on the Mohs scale and can also cut it. Diamonds can scratch other diamonds, but this can result in damage to one or both stones. Hardness tests are infrequently used in practical gemology because of their potentially destructive nature. The extreme hardness and high value of diamond means that gems are typically polished slowly, using painstaking traditional techniques and greater attention to detail than
6862-454: Is the case with most other gemstones; these tend to result in extremely flat, highly polished facets with exceptionally sharp facet edges. Diamonds also possess an extremely high refractive index and fairly high dispersion. Taken together, these factors affect the overall appearance of a polished diamond and most diamantaires still rely upon skilled use of a loupe (magnifying glass) to identify diamonds "by eye". Somewhat related to hardness
7008-736: The Angolan Civil War . It was reported that Zimbabwe had more than 2,000 combat troops, including 20 military intelligence officers, deployed in Angola whose presence has helped the Angolan Armed Forces to overrun Jonas Savimbi 's strongholds, according to reports reaching the Zimbabwe Independent. Zimbabwe deployed a national contingent to UNOSOM II on 15 January 1993. The initial deployment comprised an infantry company group of 163 personnel under Major Vitalis Chigume. By June 1993
7154-731: The Earth's mantle , and most of this section discusses those diamonds. However, there are other sources. Some blocks of the crust, or terranes , have been buried deep enough as the crust thickened so they experienced ultra-high-pressure metamorphism . These have evenly distributed microdiamonds that show no sign of transport by magma. In addition, when meteorites strike the ground, the shock wave can produce high enough temperatures and pressures for microdiamonds and nanodiamonds to form. Impact-type microdiamonds can be used as an indicator of ancient impact craters. Popigai impact structure in Russia may have
7300-645: The Federation of Rhodesia and Nyasaland . A Joint High Command created in March 1980 to oversee integration of the formerly belligerent Rhodesian Security Forces , Zimbabwe African National Liberation Army (ZANLA), and the Zimbabwe People's Revolutionary Army (ZIPRA) officially established the Zimbabwe National Army in late 1980, nearly a year after the end of the Rhodesian Bush War . The mission statement of
7446-553: The New England area in New South Wales , Australia. These diamonds are generally small, perfect to semiperfect octahedra, and are used to polish other diamonds. Their hardness is associated with the crystal growth form, which is single-stage crystal growth. Most other diamonds show more evidence of multiple growth stages, which produce inclusions, flaws, and defect planes in the crystal lattice, all of which affect their hardness. It
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#17328510341747592-614: The Parachute Group, One Commando Battalion and the AFZ. Men and equipment were moved to Chimoio in Mozambique, with a Forward Replenishment Point (FRP) being established at Grand Reef near Mutare . Intelligence sources had indicated that RENAMO's main regional base in Manica province was at Muxamba and that Casa Banana was the national stronghold of RENAMO. Both bases had to be attacked and Muxamba
7738-523: The Patriotic Front . Especially problematic was the integration of Soviet and Chinese weapons with the Rhodesian NATO standard arms, which had different gauges and calibers. The Zimbabwean government initially ordered that the guerrillas' Soviet or Chinese arms be placed into storage, hoping to simplify maintenance and logistics by re-issuing only former Rhodesian weapons and ammunition. This decision
7884-673: The Royal Rhodesia Regiment was founded, and by the time Salisbury joined the Central African Federation there were three battalions. As Southern Rhodesia was the dominant territory in the federation, its officers represented the senior commanders in charge of all federal units. During this period Southern Rhodesians served overseas on active duty for the British Empire , most notably in Malaya , Kuwait , and Aden . When
8030-503: The Special Forces of Zimbabwe the 1 Parachute Regiment , Zimbabwe Special Air Service (SAS), and was supported by the Air Force of Zimbabwe (AFZ). Bad weather conditions and the difficult mountainous terrain reduced the use of aircraft, and all the trooping had to be done by helicopters. The movement of troops on the ground was also difficult. Four contacts were made and two RENAMO bases were destroyed. However, most RENAMO elements in
8176-948: The University of Zimbabwe found that operations at the diamond fields are releasing dangerous chemicals into the Save River . This is having dire consequences on the communities that live downstream from the river and there was panic in October 2012 when residents of these communities learned of the findings of the report and the potential medical effects this could have. Three diamond mining companies were found to be at fault; Anjin, Diamond Mining Corporation and Marange Resources. In 2013, US-based investigative platform 100 Reporters published Central Intelligence Organization (CIO) documents revealing how $ 1 billion diamond revenues and support from companies including Mbada, Anjin and China Sonangol, would be invested in security and intelligence measures designed to rig
8322-546: The Wawa belt of the Superior province in Canada and microdiamonds in the island arc of Japan are found in a type of rock called lamprophyre . Kimberlites can be found in narrow (1 to 4 meters) dikes and sills, and in pipes with diameters that range from about 75 m to 1.5 km. Fresh rock is dark bluish green to greenish gray, but after exposure rapidly turns brown and crumbles. It
8468-436: The lithosphere . Such depths occur below cratons in mantle keels , the thickest part of the lithosphere. These regions have high enough pressure and temperature to allow diamonds to form and they are not convecting, so diamonds can be stored for billions of years until a kimberlite eruption samples them. Host rocks in a mantle keel include harzburgite and lherzolite , two type of peridotite . The most dominant rock type in
8614-523: The normal color range , and applies a grading scale from "D" (colorless) to "Z" (light yellow). Yellow diamonds of high color saturation or a different color, such as pink or blue, are called fancy colored diamonds and fall under a different grading scale. In 2008, the Wittelsbach Diamond , a 35.56-carat (7.112 g) blue diamond once belonging to the King of Spain, fetched over US$ 24 million at
8760-402: The upper mantle , peridotite is an igneous rock consisting mostly of the minerals olivine and pyroxene ; it is low in silica and high in magnesium . However, diamonds in peridotite rarely survive the trip to the surface. Another common source that does keep diamonds intact is eclogite , a metamorphic rock that typically forms from basalt as an oceanic plate plunges into the mantle at
8906-487: The 35-90 age brackets; Using housing schemes to “re-orient beneficiaries” and log them on the voting roll; Deliberately congesting the Zimbabwean Electoral Commission registration by “security personnel and trusted lieutenants to delay the process as advised by Nikuv”. 19°35′26″S 32°21′08″E / 19.59056°S 32.35222°E / -19.59056; 32.35222 Diamond Diamond
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#17328510341749052-820: The Earth's mantle , although a few have come from as deep as 800 kilometres (500 mi). Under high pressure and temperature, carbon-containing fluids dissolved various minerals and replaced them with diamonds. Much more recently (hundreds to tens of million years ago), 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 gases by chemical vapor deposition (CVD). Imitation diamonds can also be made out of materials such as cubic zirconia and silicon carbide . Natural, synthetic, and imitation diamonds are most commonly distinguished using optical techniques or thermal conductivity measurements. Diamond
9198-511: The European Union to lift sanctions on ZMDC diamonds. In December 2013, the first European Union Marange auction took place in Antwerp and fetched $ 10 million for 300,000 carats, working out to a price of just over $ 30 per-carat on average. A second auction is scheduled for February 12–21, 2014 where another 300,000 carats will be sold. In March 2016, president Mugabe announced that the government
9344-493: The Marange fields. On August 11, buyers flew into the country's capital, Harare, from all over the world, including Israel, India, Lebanon and Russia to capitalise on the sale of over US$ 1.5 billion worth of diamonds. Press Reports describe the Marange find as, 'the biggest in southern Africa since diamonds were discovered in South Africa a century ago'. In September 2013, Belgian and diamond industry officials successfully lobbied
9490-518: The Mutare City Council, based on a request for burial ground, to 140 estimated by the (then) opposition Movement for Democratic Change - Tsvangirai party. The military operation, known as Operation No Return , also involved searching travellers into and out of the Mutare West area, with people found in possession of foreign currency or diamonds being detained and being forced to fill in holes on
9636-626: The Party; Populating the voters’ roll before, and during, elections to counter unfavorable voting outcomes; Parallel registration and mobilization for “statistical maneuvering, depopulation and population of hostile constituencies,” in coordination with the Registrar’s Office and an official of the Chinese Communist Party identified in the documents as Chung Huwao; Obstructing registration in the 18-35 age brackets, and over-registering voters in
9782-567: The President, placed Mugabe under effective house arrest until he agreed to resign from the presidency. Emmerson Mnangagwa, a former vice-president and senior ZANU-PF member, was later appointed as president and senior generals were rewarded with promotion or political appointment. The Zimbabwe National Army has eight brigade-sized formations, plus two district commands. These are 1 to 5 Infantry Brigades, Presidential Guard Brigade , Mechanised Brigade and Artillery Brigade, Harare District and Bulawayo District. One, now dated, web publication gave
9928-500: The Smith regime. After the independence of Mozambique in 1975, the bulk of Malawi's trade with South Africa went through Rhodesia by road via Tete. It was only in 1984 that trade via this route declined because of RENAMO attacks. It was in the wake of these developments that in June 1984 the governments of Malawi, Mozambique and Zimbabwe formed a joint security committee 13. The aim of the committee
10074-567: The ZDF could pursue into Mozambique any RENAMO elements that might have raided Zimbabwe. This was the basis on which the ZDF started planning follow-up operations which took them deep into Mozambique culminating in occupation of former RENAMO bases at Gorongosa. The first of these Zimbabwe Defence Forces (ZDF) follow-up operations was launched from Katiyo and Aberdeen in northern Manicaland , code-named Operation Lemon . The operation lasted from 5–9 December 1984. It comprised elements of 3 Infantry Brigade,
10220-594: The ZMDC. Marange Resources, Gyne Nyame and Kusena were immediately merged. Three companies sued the government over the required merger, including Anjin Industries. They lost the law suit, and ZCDC took over the Marange fields. On 4 December 2018, the Zimbabwe Cabinet approved a new "Zimbabwe National Diamond Policy" (ZNDP) which allowed four companies to participate in diamond exploration and mining at Marange. Anjin Industries
10366-720: The ZNA in the mid-1980s through Zimbabwe Defence Industries (ZDI). The operational readiness and serviceability rate of the army's weapons systems began undergoing a decline during the Second Congo War , due to an inability to source new parts and ammunition at a pace sufficient to keep up with wartime wear. Development loans to the Zimbabwean government by the World Bank and the International Monetary Fund were suspended when
10512-408: The ZNA is under the command of Lt General David Sigauke, who took over from General Edzai Absolom Chanyuka Chimonyo following the latter's death. Some Mozambican National Resistance (RENAMO) elements had crossed from Mozambique into Zimbabwe several times, had robbed some shops along the border and had burned down a timber factory. After several meetings with Mozambican officials it was agreed that
10658-546: The ZNA was accused of diverting the money into the war effort. The ZNA was also badly affected by a subsequent arms embargo imposed by the EU due to allegations of human rights abuses. One consequence of the embargo was that the ZNA was forced to retire much of its technical equipment, namely radios, of Western origin. The logistics problem was further exacerbated during the collapse of the Zimbabwean dollar against major world currencies, which led to further budgetary restraints. Over half
10804-621: The ZNA's largest external supplier of arms during the 1980s. Most of the new artillery, tanks, and APCs accepted into service after 1981 were of Chinese origin. Nevertheless, the ZNA continued to look to a number of diverse suppliers to meet its needs, including member states of the European Union and the Commonwealth of Independent States . Domestic production of small arms and ammunition, including multiple rocket launchers, small arms ammunition, artillery shells, and hand grenades, commenced for
10950-464: The actual source of the diamonds they were dealing. “They’ve just been saying, ‘We have the Kimberley Process for diamonds, so that’s that. We’ve solved the problem of blood diamonds.’” Farai Maguwu , the director of the Zimbabwe-based Centre for Research and Development, which is also a member of the Kimberley Process, said he believed Global Witness’s withdrawal was not enough to bring down
11096-470: The area, improving the accounting and auditing of Marange diamonds, and supervising exports from the mine. Many NGO’s came out in support of the plan, while others protested it as shielding Zimbabwe’s alleged grave human rights abuses. The Rapaport Group, chaired by Martin Rapaport , went so far as to ban traders on its internet diamond trading network from trading any diamonds from the Marange fields. Towards
11242-631: The army is "to defend the sovereignty, territorial integrity and national interests of Zimbabwe and to contribute to international peace and security" a mandate the force has been able live up to in the region. It is considered an integral component of the JOC, and falls under the ultimate authority of the President of Zimbabwe . The ZNA is directed by a Chief of the Army, the senior official being an Army Chief of Staff. Zimbabwe's highest ranking army officer as of October 2023
11388-451: The army's tanks and armoured vehicles were rendered unserviceable due to a lack of funds to source spare parts, fuel, or training ammunition. To raise funds, the ZNA was forced to auction off much of its trailers, ammunition trucks, and engineering vehicles. Army ammunition continued to be sourced from ZDI, but the latter suspended operations in 2015 when the ZNA defaulted on its payments. In February 2017, Zimbabwean officials revealed that
11534-462: The atoms form tetrahedra, with each bound to four nearest neighbors. Tetrahedra are rigid, the bonds are strong, and, of all known substances, diamond has the greatest number of atoms per unit volume, which is why it is both the hardest and the least compressible . It also has a high density, ranging from 3150 to 3530 kilograms per cubic metre (over three times the density of water) in natural diamonds and 3520 kg/m in pure diamond. In graphite,
11680-420: The atoms, they have many facets that belong to a cube , octahedron, rhombicosidodecahedron , tetrakis hexahedron , or disdyakis dodecahedron . The crystals can have rounded-off and unexpressive edges and can be elongated. Diamonds (especially those with rounded crystal faces) are commonly found coated in nyf , an opaque gum-like skin. Some diamonds contain opaque fibers. They are referred to as opaque if
11826-412: The bases managed to escape and only eight were captured. The ZDF considered this operation as a major failure and the code word Lemon was co-opted to mean any failure in all subsequent operations. It was further established that there were no other permanent bases in the area, only some advance posts and temporary bases used by RENAMO as launching pads for food raids into Zimbabwe. It was also revealed for
11972-410: The bonds between nearest neighbors are even stronger, but the bonds between parallel adjacent planes are weak, so the planes easily slip past each other. Thus, graphite is much softer than diamond. However, the stronger bonds make graphite less flammable. Diamonds have been adopted for many uses because of the material's exceptional physical characteristics. It has the highest thermal conductivity and
12118-519: The cantonment of the ZANLA and ZIPRA under Operation Midford , British Army trainers (the British Military Advisory and Training Team, BMATT) oversaw the integration of guerrilla fighters into one unified army. A battalion structure was overlaid on the existing Rhodesian Army . For the first year a system was followed where the top-performing candidate became battalion commander. If he or she
12264-507: The carbon source is more likely carbonate rocks and organic carbon in sediments, rather than coal. Diamonds are far from evenly distributed over the Earth. A rule of thumb known as Clifford's rule states that they are almost always found in kimberlites on the oldest part of cratons , the stable cores of continents with typical ages of 2.5 billion years or more. However, there are exceptions. The Argyle diamond mine in Australia ,
12410-436: The coloration, while pure or nearly pure diamonds are transparent and colorless. Most diamond impurities replace a carbon atom in the crystal lattice , known as a carbon flaw . The most common impurity, nitrogen, causes a slight to intense yellow coloration depending upon the type and concentration of nitrogen present. The Gemological Institute of America (GIA) classifies low saturation yellow and brown diamonds as diamonds in
12556-644: The company was readying trial mining operations when the Government of Zimbabwe took over the rights via the Zimbabwe Mining Development Corporation , despite African Consolidated Resources winning a court case allowing them to continue mining. In April 2010 the High Court of Zimbabwe ruled that the government could sell diamonds from Marange as it dismissed an application from British-based African Consolidated Resources to stop diamond sales from
12702-497: The compositions of minerals are analyzed as if they were in equilibrium with mantle minerals. Finding kimberlites requires persistence, and only a small fraction contain diamonds that are commercially viable. The only major discoveries since about 1980 have been in Canada. Since existing mines have lifetimes of as little as 25 years, there could be a shortage of new diamonds in the future. Diamonds are dated by analyzing inclusions using
12848-608: The creation of two major insurgent armies, expansion of the Rhodesian Army , and militarisation of local society. By 1980 there were an estimated 150,000 Zimbabweans with military training or experience, access to arms, and allegiance to an established political organisation. Conscription had been introduced in 1955, and the National Service Act in 1976 provided for 12 months of full-time military service regardless of rank. Three-year reservist obligations for white, Coloured , and Asian males also continued. Personnel strength of
12994-598: The decay of radioactive isotopes. Depending on the elemental abundances, one can look at the decay of rubidium to strontium , samarium to neodymium , uranium to lead , argon-40 to argon-39 , or rhenium to osmium . Those found in kimberlites have ages ranging from 1 to 3.5 billion years , and there can be multiple ages in the same kimberlite, indicating multiple episodes of diamond formation. The kimberlites themselves are much younger. Most of them have ages between tens of millions and 300 million years old, although there are some older exceptions (Argyle, Premier and Wawa). Thus,
13140-522: The deployment had built up to a full battalion of 939 soldiers. This battalion was rotated every six months until October 1994, when new deployments ceased, and the last Zimbabweans were finally withdrawn in early 1995. Four Zimbabweans lost their lives during the UNOSOM mission in Somalia. These included Private Themba Moyo, who was killed by local militia in an altercation during August 1994. In January 2015
13286-513: The deployment of Tanzanian troops north of the Zambezi river and Zimbabwean troops to the south. The decision to send Zimbabwean troops to help restore law and order in Mozambique was partly influenced by Zimbabwe's close relationship with the Mozambican government which dates back to FRELIMO's assistance during Zimbabwe's war of liberation. There was also the underlying fact that FRELIMO and ZANU shared
13432-470: The diamond crystal lattice. Plastic deformation is the cause of color in some brown and perhaps pink and red diamonds. In order of increasing rarity, yellow diamond is followed by brown, colorless, then by blue, green, black, pink, orange, purple, and red. "Black", or carbonado , diamonds are not truly black, but rather contain numerous dark inclusions that give the gems their dark appearance. Colored diamonds contain impurities or structural defects that cause
13578-456: The diamond fields. On 28 January 2009, the government announced plans to resettle some 4,700 villagers from Chiadzwa to the 12,000 ha Transau Farm, on the Odzi River . Although Manicaland Provincial Governor Christopher Mushohwe said that the move had the full support of the local traditional leaders , Chiadzwa villagers protested the resettlement. In 2010 Zimbabwe's High Court ruled that
13724-501: The diamond lattice is 1.732 a /4 where a is the lattice constant, usually given in Angstrøms as a = 3.567 Å, which is 0.3567 nm. 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. Viewed from a <1 1 1> crystallographic direction , it
13870-415: The diamond lattice, donating a hole into the valence band . Substantial conductivity is commonly observed in nominally undoped diamond grown by chemical vapor deposition . This conductivity is associated with hydrogen -related species adsorbed at the surface, and it can be removed by annealing or other surface treatments. Thin needles of diamond can be made to vary their electronic band gap from
14016-407: The diamonds' surface cannot be wet by water, but can be easily wet and stuck by oil. This property can be utilized to extract diamonds using oil when making synthetic diamonds. However, when diamond surfaces are chemically modified with certain ions, they are expected to become so hydrophilic that they can stabilize multiple layers of water ice at human body temperature . The surface of diamonds
14162-475: The disputed fields. In September 2010, the Zimbabwe High Court formally revoked a ruling from a year earlier that restored mining rights to British-based, African Consolidated Resources Plc. As of February 2014, the diamond fields were operated by seven private entities, all of which are partnered with the Zimbabwe government under the affiliate Zimbabwe Mining Development Corporation (ZMDC). All seven of
14308-502: The effort no longer effectively ensured that conflict diamonds did not make their way onto retail markets. The organization is the first advocacy group to leave the program. While the organization had expressed concerns over the operation of the Kimberley Process for some time, the final straw leading to its withdrawal was the decision to allow Zimbabwe to export diamonds from the Marange fields, where there have been reports of widespread human rights abuses by government security forces. “It’s
14454-590: The elections. The article identified the Chinese role (including an official from the Chinese Communist Party), and alleged kickbacks to leaders in the SADC, dated May 2013, with the intent of having Mugabe become chair. Soon after the elections, this came to pass. The CIO listed specific steps taken to numerically rig the polls: "Registering less than ten real voters on “any given day with direct command from Nikuv” and
14600-527: The end of 2009, it was claimed that Marange diamonds were being smuggled out of Zimbabwe through Mozambique . On 6 May 2010, the KP Chair reminded all participants that they should maintain vigilance to ensure that Marange diamonds comply with the Kimberley Process Certification Scheme . The five-page notice also included photographs and descriptions of rough diamonds from the Marange fields: "On first sight, strong 'gravel' impression resembling rounded pebbles in
14746-599: The entire Kimberley Process. But, he said, “it’s a very big blow. The Kimberley Process will never be the same without the Global Witness,” Mr. Maguwu said. “A very influential member of the Kimberley Process has cast a vote of no confidence in the Kimberley Process, which will affect the way the whole world views the Kimberley Process going forward.” A 2012 study commissioned by the Zimbabwe Environmental Lawyers Association (ZELA) and conducted by
14892-464: The federation was dissolved in 1963, Southern Rhodesia retained the personnel raised in its territory, including the largest proportion of white soldiers – some 3,400 of the 7,000 men who served in the defunct Federal Army. Over objections raised by newly independent African governments in Northern Rhodesia ( Zambia ) and Nyasaland ( Malawi ), it also claimed the majority of armoured vehicles and
15038-449: The fibers grow from a clear substrate or fibrous if they occupy the entire crystal. Their colors range from yellow to green or gray, sometimes with cloud-like white to gray impurities. Their most common shape is cuboidal, but they can also form octahedra, dodecahedra, macles, or combined shapes. The structure is the result of numerous impurities with sizes between 1 and 5 microns. These diamonds probably formed in kimberlite magma and sampled
15184-583: The first raid on Cassa Banana. However, considering the amount of effort, the numbers of troops involved on both sides, and the time it took to capture the base, there must have been a lot of deaths and injuries on both sides. This corridor is a tarred 263-kilometre (163 mi) road running from Nyamapanda on the Zimbabwean border through the Mozambican city of Tete to Zobue on the Malawi border. After UDI in 1965, this route carried Rhodesian goods to and from Malawi, which had not applied United Nations sanctions against
15330-473: The first time that the main RENAMO bases were at Messinse, Chito, Nyazonia, Buetoni, Gorongosa Central Base and Casa Banana. The report for Operation Lemon was taken seriously by the commanders of the ZDF, and in July 1985 preparations for major offensive operations were started. Rehearsals for a Fireforce operation were carried out at Inkomo Barracks near Harare . Three infantry brigades were mobilised together with
15476-402: The government could sell Marange diamonds. International pressure group Global Witness warned Zimbabwe against selling diamonds until the government complied with plans agreed with diamond monitors, the Kimberley Process to reform mining at Marange. In June 2010 the Kimberley Process monitor appointed to review procedures and conditions at Marange reported that, "Based on evidence provided by
15622-470: The government of Zimbabwe and private investors, and on...first-hand assessment of the situation, Zimbabwe has satisfied the minimum requirements of the KPCS for trade in rough diamonds". In September 2010, the Zimbabwe High Court formally revoked a ruling from a year earlier that restored mining rights to British-based, African Consolidated Resources Plc. In August 2010 Zimbabwe resumed the sale of diamonds from
15768-605: The government to take control of the Chiadzwa diamond fields. On 5 November 2009, however, the Kimberley Process conducted its annual meeting in Namibia and decided against the suspension of Zimbabwe. Instead, it recommended and then implemented with the compliance of the Zimbabwean government a 12-month working plan to monitor diamonds mined from the Marange field. The plan is aimed towards preventing exports curbing illegal digging, stopping smuggling of diamonds from Marange, better securing
15914-541: The government, but a black market rapidly developed, offering better prices. Although the official plan was for the government to mine at Marange, in practice mining has been carried out to the benefit of senior government and Zanu-PF officials and those close to them, with little income returned to the government. Speaking anonymously, a Harare -based diplomat said A lot of leaders of the political regime are involved in trading. They have their own diggers and traders. But it's all to their personal account. They've all got
16060-408: The hardness and transparency of diamond, are the reasons that diamond anvil cells are the main tool for high pressure experiments. These anvils have reached pressures of 600 GPa . Much higher pressures may be possible with nanocrystalline diamonds. Usually, attempting to deform bulk diamond crystal by tension or bending results in brittle fracture. However, when single crystalline diamond
16206-455: The highest sound velocity. It has low adhesion and friction, and its coefficient of thermal expansion is extremely low. Its optical transparency extends from the far infrared to the deep ultraviolet and it has high optical dispersion . It also has high electrical resistance. It is chemically inert, not reacting with most corrosive substances, and has excellent biological compatibility. The equilibrium pressure and temperature conditions for
16352-422: The imbalance caused by death, emigration, or retirement. By the outbreak of the Second Congo War , only a handful of the officer corps had seen action. An interim measure was the rapid promotion of troops from non-combat units, often selected for their political connections rather than leadership competence. Theoretically, promotions continue to be based on the pre-independence system, which dictates officers below
16498-579: The infantry brigade organisation as: These are the Zimbabwe National Army ranks authorised for use today and their equivalent Commonwealth designations. The ranking order is largely based on the British system, with the Air Force of Zimbabwe maintaining separate titles inherited from the Rhodesian Air Force . The ZNA lost many of its best trained and experienced officers in the early 1990s, failing to recruit or instruct enough personnel to make up for
16644-423: The kimberlites formed independently of the diamonds and served only to transport them to the surface. Kimberlites are also much younger than the cratons they have erupted through. The reason for the lack of older kimberlites is unknown, but it suggests there was some change in mantle chemistry or tectonics. No kimberlite has erupted in human history. Most gem-quality diamonds come from depths of 150–250 km in
16790-411: The largest producer of diamonds by weight in the world, is located in a mobile belt , also known as an orogenic belt , a weaker zone surrounding the central craton that has undergone compressional tectonics. Instead of kimberlite , the host rock is lamproite . Lamproites with diamonds that are not economically viable are also found in the United States, India, and Australia. In addition, diamonds in
16936-467: The macroscopic geometry of a diamond contributes to its resistance to breakage. Diamond has a cleavage plane and is therefore more fragile in some orientations than others. Diamond cutters use this attribute to cleave some stones before faceting them. "Impact toughness" is one of the main indexes to measure the quality of synthetic industrial diamonds. Diamond has compressive yield strength of 130–140 GPa. This exceptionally high value, along with
17082-591: The melting point of diamond increases slowly with increasing pressure; but at pressures of hundreds of GPa, it decreases. At high pressures, silicon and germanium have a BC8 body-centered cubic crystal structure, and a similar structure is predicted for carbon at high pressures. At 0 K , the transition is predicted to occur at 1100 GPa . Results published in an article in the scientific journal Nature Physics in 2010 suggest that, at ultra-high pressures and temperatures (about 10 million atmospheres or 1 TPa and 50,000 °C), diamond melts into
17228-579: The melts to carry diamonds to the surface before they dissolve. Kimberlite pipes can be difficult to find. They weather quickly (within a few years after exposure) and tend to have lower topographic relief than surrounding rock. If they are visible in outcrops, the diamonds are never visible because they are so rare. In any case, kimberlites are often covered with vegetation, sediments, soils, or lakes. In modern searches, geophysical methods such as aeromagnetic surveys , electrical resistivity , and gravimetry , help identify promising regions to explore. This
17374-504: The mission". In June 2018, after Zimbabwean President Robert Mugabe had been replaced by President Emmerson Mnangagwa , it was reported that the ZDF training mission to Equatorial Guinea was continuing. A photograph published at the time shows Zimbabwean soldiers wearing AU brassards, suggesting the training mission had African Union endorsement. Between 13 November and 18 December 2017 the Zimbabwe Defence Forces deployed in
17520-507: The most egregious situation that we’ve seen since the Kimberley Process was launched, where diamonds have been fueling violence and human rights violations, and the Kimberley has really failed to deal with that effectively,” said Annie Dunnebacke, the senior campaigner for Global Witness. The diamond industry was “hiding behind the Kimberley Process,” Ms. Dunnebacke said, adding that many traders and dealers did not perform due diligence in checking
17666-469: The normal 5.6 eV to near zero by selective mechanical deformation. High-purity diamond wafers 5 cm in diameter exhibit perfect resistance in one direction and perfect conductance in the other, creating the possibility of using them for quantum data storage. The material contains only 3 parts per million of nitrogen. The diamond was grown on a stepped substrate, which eliminated cracking. Diamonds are naturally lipophilic and hydrophobic , which means
17812-421: The paratroopers had entered the base, the infantry battalions, which were close by, were ordered to move in and occupy strategic positions. The Fireforce then moved on to deal with the several pockets of resistance from the smaller RENAMO bases all along the Gorongosa Mountains. It took the whole day to silence all of these pockets of resistance. There is no official Zimbabwean record of the number of casualties on
17958-675: The potent strike aircraft of the Royal Rhodesian Air Force . Recruitment and training for an insurgent campaign against the colony's administration by rival African nationalists from the Zimbabwe African People's Union (ZAPU) and the Zimbabwe African National Union (ZANU) began in 1963, and intensified after Rhodesia's Unilateral Declaration of Independence in 1965. The Rhodesian Bush War , which lasted roughly fifteen years until late 1979, resulted in
18104-620: The presence of natural minerals and oxides. The clarity scale grades the diamond based on the color, size, location of impurity and quantity of clarity visible under 10x magnification. Inclusions in diamond can be extracted by optical methods. The process is to take pre-enhancement images, identifying the inclusion removal part and finally removing the diamond facets and noises. Between 25% and 35% of natural diamonds exhibit some degree of fluorescence when examined under invisible long-wave ultraviolet light or higher energy radiation sources such as X-rays and lasers. Incandescent lighting will not cause
18250-401: The presidency once her aging husband could no longer fulfil that role. Senior members of the defence forces and ZANU-PF reportedly saw this group as a threat to their authority and their own plans, and believed the group did not represent the generation that had suffered during the liberation war of 1966−1980. The defence forces arrested several members of the group and, while showing respect to
18396-450: The prestigious tournament at the last minute after the original host country, Morocco, pulled out. This initial deployment to Equatorial Guinea was followed from November 2015 by an ongoing training mission. When one ZDF training contingent returned to Harare in January 2017, following a year-long deployment to Equatorial Guinea, it was suggested by senior ministers that was "not the end of
18542-521: The private companies were allegedly affiliated with Zimbabwe ex-military or political officials. The seven companies then operating were: Marange Resources, Anjin Investments Ltd., Diamond Mining Company, Gyne Nyame Resources, Jinan Mining Ltd., Kusena Diamonds, and Mbada Diamonds. However, in 2015 all diamond mining companies in Zimbabwe were forced to quit mining or merge into the newly-created Zimbabwe Consolidated Diamond Company (ZCDC), which replaced
18688-425: The rank of lieutenant colonel pass a proficiency examination to qualify for advancement. In times of downscaling, those with poorer marks must retire or accept an immediate demotion . •Lt General David Sigauke(2021-2023) At its formation in 1980, the ZNA was overburdened with a surplus of arms due to having inherited the inventories of the former Rhodesian Army as well as the two constituent insurgent factions of
18834-476: The regular army peaked at 20,000 active members (half of them whites) and 2,300 with the air force. The paramilitary BSAP had 11,000 police and a reserve of 35,000. These uniform commands and others – including 20,000 Security Force Auxiliaries loyal to interim politicians and a 3,500-man Guard Force for securing protected villages – fell under the authority of Combined Operations (COMOPS), headed by Lieutenant-General Peter Walls . The Zimbabwe National Army
18980-529: The size of the resulting indentation, a Vickers hardness value for the material can be determined. Diamond's great hardness relative to other materials has been known since antiquity, and is the source of its name. This does not mean that it is infinitely hard, indestructible, or unscratchable. Indeed, diamonds can be scratched by other diamonds and worn down over time even by softer materials, such as vinyl phonograph records . Diamond hardness depends on its purity, crystalline perfection, and orientation: hardness
19126-419: 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 rapidly 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 graphite–diamond–liquid carbon triple point,
19272-401: The use of such a menagerie of disparate equipment within individual battalions, forcing the ZNA to standardize equipment on the battalion and later the brigade level. Unfortunately this resulted in additional problems, such as the use of separate communications equipment in certain brigades which were otherwise incompatible with those of other units. The People's Republic of China emerged as
19418-454: The volatiles. Diamonds can also form polycrystalline aggregates. There have been attempts to classify them into groups with names such as boart , ballas , stewartite, and framesite, but there is no widely accepted set of criteria. Carbonado, a type in which the diamond grains were sintered (fused without melting by the application of heat and pressure), is black in color and tougher than single crystal diamond. It has never been observed in
19564-430: The world's largest diamond deposit, estimated at trillions of carats, and formed by an asteroid impact. A common misconception is that diamonds form from highly compressed coal . Coal is formed from buried prehistoric plants, and most diamonds that have been dated are far older than the first land plants . It is possible that diamonds can form from coal in subduction zones , but diamonds formed in this way are rare, and
19710-589: Was Chief Military Observer of UNAVEM II between December 1992 and July 1993. During UNAVEM III a Zimbabwean battalion was deployed to eastern Angola, based in the town of Saurimo. Nine Zimbabwean peacekeepers died during the UNAVEM deployments. After several hints, some of which the Zimbabwean Government denied, for the first time the ZDF Commander, General Constantine Chiwenga, acknowledged ZNA involvement in
19856-483: Was detailed to attack specific suspected RENAMO positions around the Gorongossa Mountains. It was during this three pronged attack that one helicopter flew overhead Cassa Banana airstrip and the pilot noticed a green pickup truck disappearing into some bushes. It was then that the pilot recognised the place as that given at the briefing as Cassa Banana. The jets from Thornhill , which were already in place overhead
20002-550: Was formed in 1980 from elements of the Rhodesian Army , integrated to a greater or lesser extent with combatants from the Zimbabwe African National Liberation Army (ZANLA) and Zimbabwe People's Revolutionary Army (ZIPRA) guerrilla movements (the armed wings of, respectively, the Zimbabwe African National Union (ZANU) and Zimbabwe African People's Union (ZAPU). Following majority rule in April 1980 and
20148-529: Was from ZANLA, then his or her second-in-command was the top-performing ZIPRA candidate, and vice versa. This ensured a balance between the two movements in the command structure. From early 1981 this system was abandoned in favour of political appointments, and ZANLA/ZANU fighters consequently quickly formed the majority of battalion commanders in the ZNA. The ZNA was originally formed into four brigades , 1 Brigade, Matabeleland, 2 Brigade, Mashonaland, 3 Brigade, Manicaland, and 4 Brigade, Masavingo. These comprised
20294-517: Was later overturned when it became clear that the Rhodesian era weapons were insufficient to equip the ZNA, especially after a significant percentage of its 7.62×51mm NATO ammunition stockpiles were destroyed in a sabotage action around 1981. The guerrillas' former arms were brought out of storage and re-issued to individual units, being supplemented by additional supplies of Soviet-style arms from North Korea. Serious logistical difficulties resulted from
20440-411: Was launched on 20 August 1985 by elements of 3 Brigade, supported by the Parachute Group and the AFZ. The operation went on for four days with minor problems for the ZDF. One helicopter was riddled with small arms fire but managed to return to Chimoio. Intelligence sources had indicated that Cassa Banana, RENAMO's national headquarters had a strength of 400 elements. However, the organisation maintained
20586-486: Was nationalizing its diamond mines. Diamond-related mining licenses were revoked or not renewed. Mbada Diamonds and Anjin Investments have sued the government in the country's high court. The court ruled twice in their favor, yet the government did not renew any license. With the workers out of the mines, security needs to be increased as looters are targeting the left-out mines. The BBC claims Zimbabwe's security forces have
20732-468: Was providing covert and overt support to opposition movements such as UNITA in Angola and RENAMO in Mozambique reflected the extension of the Cold War to Southern Africa. There were three United Nations Missions to Angola under UNAVEM. UNAVEM I (January 1989 to June 1991) and UNAVEM II (May/June 1991 to February 1995) involved small numbers of unarmed military observers. Brigadier Michael Nyambuya of Zimbabwe
20878-749: Was revived, and was named one of the companies. Anjin began operations at Marange on 1 March 2019 subsequently taking over the highly profitable "Portal B" at Marange from ZCDC. Anjin is a joint venture between the Chinese firm Anhui Foreign Economic Construction Group (AFECC) and the Zimbabwe Defence Industries . A mineral rush began in September 2006, but accelerated following the government take-over. By mid-December 2006, around 10,000 illegal artisanal miners were working very small plots at Marange, and an immediate water, sanitation and housing crisis developed. The miners initially sold their diamonds to
21024-450: Was sent, after some police officers began refusing orders to shoot the illegal miners. Up to 150 of the estimated 30,000 illegal miners were shot from helicopter gunships. In 2008 some Zimbabwean lawyers and opposition politicians from Mutare claimed that Shiri was the prime mover behind the military assaults on illegal diggers in the diamond mines in the east of Zimbabwe. Estimates of the death toll by mid-December range from 83 reported by
21170-515: Was targeted first, being only 70 kilometres south of Chimoio. The most important consideration however, was the hope that activities around Muxamba might divert RENAMO's attention from monitoring too closely the movement of the three heavily armed Zimbabwean infantry battalions marching from Chimoio towards the Gorongosa Mountains. Muxamba was believed to hold at least 400 RENAMO elements commanded by Major General Mabachi. The attack on Muxamba
21316-659: Was to monitor operations on a day-to-day basis and to attempt to remove all security threats along the Tete Corridor. Zimbabwe's First Mechanised Battalion was ordered to move into Mozambique and they established their headquarters in Tete thereby securing the strategic bridge crossing the Zambezi River. In 1985, President Samora Machel of Mozambique formally requested the governments of Tanzania and Zimbabwe to contribute troops for "the restoration of law and order" in Mozambique. This led to
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