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Lesotho Promise
The Lesotho Promise, a 603 carat (121 g) diamond stone of exceptional colour was unearthed on 22 August 2006 at the Letseng diamond mine in the mountain kingdom of Lesotho. Announced on 4 October 2006, it was the largest reported find this century and the 15th largest diamond ever found. The stone is rated 'D', the top colour band for diamonds. The diamond was sold at an auction on 9 October 2006 in Antwerp, Belgium, for US$12.4 million.BBC News Online, "Massive diamond bought for $12m", BBC, http://news.bbc.co.uk/2/hi/europe/6034429.stm (accessed 2006-10-09) The buyer, The South African Diamond Corporatio(SAFDICO) expected to sell the diamond for more than US$20 million after cutting. In July 2007 the finished stones were unveiled. The largest gem cut from the crystal is a pear-shaped diamond, and the smallest is a round brilliant. In all, twenty-six stones were fashioned from the rough gem, figuring as seven pear shapes, four emerald cuts, thirteen round brilliants and one he ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carat (unit)
The carat (ct) is a unit of mass equal to or 0.00643 troy oz, and is used for measuring gemstones and pearls. The current definition, sometimes known as the metric carat, was adopted in 1907 at the Fourth General Conference on Weights and Measures, and soon afterwards in many countries around the world. The carat is divisible into 100 ''points'' of 2 mg. Other subdivisions, and slightly different mass values, have been used in the past in different locations. In terms of diamonds, a paragon is a flawless stone of at least 100 carats (20 g). The ANSI X.12 EDI standard abbreviation for the carat is CD. Etymology First attested in English in the mid-15th century, the word ''carat'' comes from Italian ''carato'', which comes from Arabic '' qīrāṭ '' قيراط , in turn borrowed from Greek ''kerátion'' κεράτιον 'carob seed', a diminutive of ''keras'' 'horn'. It was a unit of weight, equal to 1/1728 (1/12) of a pound (see Mina (unit)). History Carob seeds ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diamond
Diamond is a Allotropes of carbon, solid form of the element carbon with its atoms arranged in a crystal structure called diamond cubic. Another solid form of carbon known as graphite is the Chemical stability, chemically stable form of carbon at Standard conditions for temperature and pressure, room temperature and pressure, but diamond is metastable and converts to it at a negligible rate under those conditions. Diamond has the highest Scratch hardness, 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 is extremely rigid, few types of impurity can contaminate it (two exceptions are boron and nitrogen). Small numbers of lattice defect, defects or impurities (about one per million of lattice atoms) color diamond blue (bor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rock (geology)
In geology, rock (or stone) is any naturally occurring solid mass or aggregate of minerals or mineraloid matter. It is categorized by the minerals included, its chemical composition, and the way in which it is formed. Rocks form the Earth's outer solid layer, the crust, and most of its interior, except for the liquid outer core and pockets of magma in the asthenosphere. The study of rocks involves multiple subdisciplines of geology, including petrology and mineralogy. It may be limited to rocks found on Earth, or it may include planetary geology that studies the rocks of other celestial objects. Rocks are usually grouped into three main groups: igneous rocks, sedimentary rocks and metamorphic rocks. Igneous rocks are formed when magma cools in the Earth's crust, or lava cools on the ground surface or the seabed. Sedimentary rocks are formed by diagenesis and lithification of sediments, which in turn are formed by the weathering, transport, and deposition of existing ro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Letseng Diamond Mine
The Letšeng Diamond Mine, found in the landlocked Southern African kingdom of Lesotho, is owned by Gem Diamonds, Ltd. and the government of Lesotho, and at an elevation of 3,100 m (10,000 ft) it is the world's highest diamond mine. Production It is characterised by extremely low grade ore (less than /hundred tons) and is known for producing huge diamonds, having the highest percentage of large diamonds (greater than ), giving it the highest dollar value per carat of any diamond mine. The world average is roughly US$81 per carat, while Letšeng averaged over US$1,894 per carat for the first six months of 2007. Unusual for Africa, and due to the elevation, temperatures at the mine drop to -20 °C, and snowfalls are common in winter. Geography Climate Letšeng has an alpine tundra climate (''ET'', according to the Köppen climate classification). This means that Letšeng has a chilly climate with fairly cool temperatures throughout the year, even for Le ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lesotho
Lesotho ( ), officially the Kingdom of Lesotho, is a country landlocked country, landlocked as an Enclave and exclave, enclave in South Africa. It is situated in the Maloti Mountains and contains the Thabana Ntlenyana, highest mountains in Southern Africa. It has an area of over and has a population of about million. It was previously the British Crown colony of Basutoland, which declared independence from the United Kingdom on 4 October 1966. It is a fully sovereign state and is a member of the United Nations, the Commonwealth of Nations, the African Union, and the Southern African Development Community. The name ''Lesotho'' roughly translates to "land of the Sotho". History Basutoland Basutoland emerged as a single body politic, polity under King Moshoeshoe I in 1822. Moshoeshoe, a son of Mokhachane, a minor tribal chief, chief of the Bakoteli lineage, formed his own clan and became a chief around 1804. Between 1820 and 1823, he and his followers settled at the Buth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mail & Guardian
The ''Mail & Guardian'' is a South African weekly newspaper and website, published by M&G Media in Johannesburg, South Africa. It focuses on political analysis, investigative reporting, Southern African news, local arts, music and popular culture. It is considered a newspaper of record for South Africa. History The publication began as the ''Weekly Mail'', an alternative newspaper by a group of journalists in 1985 after the closure of two leading liberal newspapers, ''The Rand Daily Mail'' and ''Sunday Express''. ''Weekly Mail'' was one of the first newspapers to use Apple Mac desktop publishing. The ''Weekly Mail'' criticised the government and its apartheid policies, which led to the banning of the paper in 1988 by then State President P. W. Botha. The paper was renamed the ''Weekly Mail & Guardian'' from 30 July 1993. The London-based Guardian Media Group (GMG), the publisher of ''The Guardian'', became the majority shareholder of the print edition in 1995, and the name was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diamond Color
A chemically pure and structurally perfect diamond is perfectly transparent with no hue, or ''color''. However, in reality almost no gem-sized natural diamonds are absolutely perfect. The color of a diamond may be affected by chemical impurities and/or structural defects in the crystal lattice. Depending on the hue and intensity of a diamond's coloration, a diamond's color can either detract from or enhance its value. For example, most white diamonds are discounted in price when more yellow hue is detectable, while intense pink diamonds or blue diamonds (such as the Hope Diamond) can be dramatically more valuable. Of all colored diamonds, red diamonds are the rarest. The Aurora Pyramid of Hope displays a spectacular array of naturally colored diamonds, including red diamonds. History of color grading Color grading of diamonds was performed as a step of sorting rough diamonds for sale by the London Diamond Syndicate. As the diamond trade developed, early diamond grades were in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Auction
An auction is usually a process of buying and selling goods or services by offering them up for bids, taking bids, and then selling the item to the highest bidder or buying the item from the lowest bidder. Some exceptions to this definition exist and are described in the section about different types. The branch of economic theory dealing with auction types and participants' behavior in auctions is called auction theory. The open ascending price auction is arguably the most common form of auction and has been used throughout history. Participants bid openly against one another, with each subsequent bid being higher than the previous bid. An auctioneer may announce prices, while bidders submit bids vocally or electronically. Auctions are applied for trade in diverse contexts. These contexts include antiques, paintings, rare collectibles, expensive wines, commodities, livestock, radio spectrum, used cars, real estate, online advertising, vacation packages, emission trading, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antwerp
Antwerp (; nl, Antwerpen ; french: Anvers ; es, Amberes) is the largest city in Belgium by area at and the capital of Antwerp Province in the Flemish Region. With a population of 520,504,Statistics Belgium; ''Loop van de bevolking per gemeente'' (Excel file) Population of all municipalities in Belgium, . Retrieved 1 November 2017. it is the most populous municipality in Belgium, and with a metropolitan population of around 1,200,000 people, it is the second-largest metrop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Belgium
Belgium, ; french: Belgique ; german: Belgien officially the Kingdom of Belgium, is a country in Northwestern Europe. The country is bordered by the Netherlands to the north, Germany to the east, Luxembourg to the southeast, France to the southwest, and the North Sea to the northwest. It covers an area of and has a population of more than 11.5 million, making it the 22nd most densely populated country in the world and the 6th most densely populated country in Europe, with a density of . Belgium is part of an area known as the Low Countries, historically a somewhat larger region than the Benelux group of states, as it also included parts of northern France. The capital and largest city is Brussels; other major cities are Antwerp, Ghent, Charleroi, Liège, Bruges, Namur, and Leuven. Belgium is a sovereign state and a federal constitutional monarchy with a parliamentary system. Its institutional organization is complex and is structured on both regional ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Dollar
The United States dollar ( symbol: $; code: USD; also abbreviated US$ or U.S. Dollar, to distinguish it from other dollar-denominated currencies; referred to as the dollar, U.S. dollar, American dollar, or colloquially buck) is the official currency of the United States and several other countries. The Coinage Act of 1792 introduced the U.S. dollar at par with the Spanish silver dollar, divided it into 100 cents, and authorized the minting of coins denominated in dollars and cents. U.S. banknotes are issued in the form of Federal Reserve Notes, popularly called greenbacks due to their predominantly green color. The monetary policy of the United States is conducted by the Federal Reserve System, which acts as the nation's central bank. The U.S. dollar was originally defined under a bimetallic standard of (0.7735 troy ounces) fine silver or, from 1837, fine gold, or $20.67 per troy ounce. The Gold Standard Act of 1900 linked the dollar solely to gold. From 1934, it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lesotho Brown
Brown diamonds are the most common color variety of natural diamonds. In most mines, brown diamonds account for 15% of production. The brown color makes them less attractive to some people as gemstones, and most are used for industrial purposes. However, improved marketing programs, especially in Australia and the United States, have resulted in brown diamonds becoming valued as gemstones and even referred to as ''chocolate diamonds''. A significant portion of the output of Australian diamond mines is brown stones. There are several causes for the brown color, including irradiation treatment, nickel impurities and lattice defects associated with plastic deformation; the last is the predominant cause, especially in pure diamonds. A high-pressure high-temperature treatment can heal lattice defects and convert brown diamonds into yellow or even colorless stones. Rise in popularity Baumgold Bros., a diamond cutter and fine jewelry importer in the 1950s and 1960s, rebranded brown di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
