A chemically pure and structurally perfect diamond is transparent with no hue, or color. However, in reality no gem-sized natural diamonds are 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 can be more valuable. Of all colored diamonds, red diamonds are the rarest; the Aurora Pyramid of Hope displays a spectacular array of colored diamonds, including red diamonds. Diamonds occur in a variety of colors—steel gray, blue, orange, green, pink to purple and black. Colored diamonds contain interstitial impurities or structural defects that cause the coloration, pure diamonds are transparent and colorless. Diamonds are scientifically classed into two main types and several subtypes, according to the nature of impurities present and how these impurities affect light absorption: Type I diamonds have nitrogen atoms as the main impurity at a concentration of 0.1%.
If the nitrogen atoms are in pairs they do not affect the diamond's color. If the nitrogen atoms are in large even-numbered aggregates they impart a yellow to brown tint. About 98% of gem diamonds are type Ia, most of these are a mixture of IaA and IaB material: these diamonds belong to the Cape series, named after the diamond-rich region known as Cape Province in North Africa, whose deposits are Type Ia. If the nitrogen atoms are dispersed throughout the crystal in isolated sites, they give the stone an intense yellow or brown tint. Synthetic diamond containing nitrogen is Type Ib. Type I diamonds absorb from 320 nm, they have a characteristic fluorescence and visible absorption spectrum. Type II diamonds have no measurable nitrogen impurities. Type II diamonds absorb in a different region of the infrared, transmit in the ultraviolet below 225 nm, unlike Type I diamonds, they have differing fluorescence characteristics, but no discernible visible absorption spectrum. Type IIa diamond can be colored pink, red, or brown due to structural anomalies arising through plastic deformation during crystal growth—these diamonds are rare, but constitute a large percentage of Australian production.
Type IIb diamonds, which account for 0.1% of gem diamonds, are light blue due to scattered boron within the crystal matrix. However, a blue-grey color may occur in Type Ia diamonds and be unrelated to boron. Not restricted to type are green diamonds, whose color is caused by GR1 color centers in the crystal lattice produced by exposure to varying quantities of radiation. Pink and red are caused by plastic deformation of the crystal lattice from pressure. Black diamonds are caused by microscopic black or gray inclusions of other materials such as graphite or sulfides and/or microscopic fractures. Opaque or opalescent white diamonds are caused by microscopic inclusions. Purple diamonds are caused by a combination of high hydrogen content; the majority of diamonds that are mined are in a range of pale yellow or brown color, termed the normal color range. Diamonds that are of intense yellow or brown, or any other color are called fancy color diamonds. Diamonds that are of the highest purity are colorless, appear a bright white.
The degree to which diamonds exhibit body color is one of the four value factors by which diamonds are assessed. Diamonds have a color grading system; this system goes from D to Z. The more colorless a diamond is, the rarer and more valuable it is because it appears white and brighter to the eye. 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 introduced by various parties in the diamond trade. Without any co-operative development these early grading systems lacked standard nomenclature, consistency; some early grading scales were. Numerous terms developed to describe diamonds of particular colors: golconda, jagers, blue white, fine white, gem blue, etc. Refers to a grading scale for diamonds in the normal color range used by internationally recognized laboratories; the scale ranges from D, colorless to Z, a pale yellow or brown color. Brown diamonds darker than K color are described using their letter grade, a descriptive phrase, for example M Faint Brown.
Diamonds with more depth of color than Z color fall into the fancy color diamond range. Diamond color is graded by comparing a sample stone to a master stone set of diamonds; each master stone is known to exhibit the least amount of body color that a diamond in that color grade may exhibit. A trained diamond grader compares a diamond of unknown grade against the series of master stones, assessing where in the range of color the diamond resides; this process occurs in a lighting box, fitted with daylight equivalent lamps. Accurate color grading can only be performed with diamond unset, as the comparison with master
Australia the Commonwealth of Australia, is a sovereign country comprising the mainland of the Australian continent, the island of Tasmania and numerous smaller islands. It is the world's sixth-largest country by total area; the neighbouring countries are Papua New Guinea and East Timor to the north. The population of 25 million is urbanised and concentrated on the eastern seaboard. Australia's capital is Canberra, its largest city is Sydney; the country's other major metropolitan areas are Melbourne, Brisbane and Adelaide. Australia was inhabited by indigenous Australians for about 60,000 years before the first British settlement in the late 18th century, it is documented. After the European exploration of the continent by Dutch explorers in 1606, who named it New Holland, Australia's eastern half was claimed by Great Britain in 1770 and settled through penal transportation to the colony of New South Wales from 26 January 1788, a date which became Australia's national day; the population grew in subsequent decades, by the 1850s most of the continent had been explored and an additional five self-governing crown colonies established.
On 1 January 1901, the six colonies federated. Australia has since maintained a stable liberal democratic political system that functions as a federal parliamentary constitutional monarchy, comprising six states and ten territories. Being the oldest and driest inhabited continent, with the least fertile soils, Australia has a landmass of 7,617,930 square kilometres. A megadiverse country, its size gives it a wide variety of landscapes, with deserts in the centre, tropical rainforests in the north-east and mountain ranges in the south-east. A gold rush began in Australia in the early 1850s, its population density, 2.8 inhabitants per square kilometre, remains among the lowest in the world. Australia generates its income from various sources including mining-related exports, telecommunications and manufacturing. Indigenous Australian rock art is the oldest and richest in the world, dating as far back as 60,000 years and spread across hundreds of thousands of sites. Australia is a developed country, with the world's 14th-largest economy.
It has a high-income economy, with the world's tenth-highest per capita income. It is a regional power, has the world's 13th-highest military expenditure. Australia has the world's ninth-largest immigrant population, with immigrants accounting for 26% of the population. Having the third-highest human development index and the eighth-highest ranked democracy globally, the country ranks in quality of life, education, economic freedom, civil liberties and political rights, with all its major cities faring well in global comparative livability surveys. Australia is a member of the United Nations, G20, Commonwealth of Nations, ANZUS, Organisation for Economic Co-operation and Development, World Trade Organization, Asia-Pacific Economic Cooperation, Pacific Islands Forum and the ASEAN Plus Six mechanism; the name Australia is derived from the Latin Terra Australis, a name used for a hypothetical continent in the Southern Hemisphere since ancient times. When Europeans first began visiting and mapping Australia in the 17th century, the name Terra Australis was applied to the new territories.
Until the early 19th century, Australia was best known as "New Holland", a name first applied by the Dutch explorer Abel Tasman in 1644 and subsequently anglicised. Terra Australis still saw occasional usage, such as in scientific texts; the name Australia was popularised by the explorer Matthew Flinders, who said it was "more agreeable to the ear, an assimilation to the names of the other great portions of the earth". The first time that Australia appears to have been used was in April 1817, when Governor Lachlan Macquarie acknowledged the receipt of Flinders' charts of Australia from Lord Bathurst. In December 1817, Macquarie recommended to the Colonial Office. In 1824, the Admiralty agreed that the continent should be known by that name; the first official published use of the new name came with the publication in 1830 of The Australia Directory by the Hydrographic Office. Colloquial names for Australia include "Oz" and "the Land Down Under". Other epithets include "the Great Southern Land", "the Lucky Country", "the Sunburnt Country", "the Wide Brown Land".
The latter two both derive from Dorothea Mackellar's 1908 poem "My Country". Human habitation of the Australian continent is estimated to have begun around 65,000 to 70,000 years ago, with the migration of people by land bridges and short sea-crossings from what is now Southeast Asia; these first inhabitants were the ancestors of modern Indigenous Australians. Aboriginal Australian culture is one of the oldest continual civilisations on earth. At the time of first European contact, most Indigenous Australians were hunter-gatherers with complex economies and societies. Recent archaeological finds suggest. Indigenous Australians have an oral culture with spiritual values based on reverence for the land and a belief in the Dreamtime; the Torres Strait Islanders, ethnically Melanesian, obtained their livelihood from seasonal horticulture and the resources of their reefs and seas. The northern coasts and waters of Australia were visited s
Diamond cutting is the practice of changing a diamond from a rough stone into a faceted gem. Cutting diamond requires specialized knowledge, tools and techniques because of its extreme difficulty; the first guild of diamond cutters and polishers was formed in 1375 in Nuremberg and led to the development of various types of "cut". This has two meanings in relation to diamonds; the first is the shape: square, so on. The second relates to the specific quality of cut within the shape, the quality and price will vary based on the cut quality. Since diamonds are one of the hardest materials, special diamond-coated surfaces are used to grind the diamond down; the first major development in diamond cutting came with the "Point Cut" during the half of the 14th century: the Point Cut follows the natural shape of an octahedral rough diamond crystal, eliminating some waste in the cutting process. Diamond cutting, as well as overall processing, is concentrated in a few cities around the world; the main diamond trading centers are Antwerp, Tel Aviv, Dubai from where roughs are sent to the main processing centers of India and China.
Diamonds are cut and polished in Surat and the Chinese cities of Guangzhou and Shenzhen. India in recent years has held between 19–31% of the world market in polished diamonds and China has held 17% of the world market share in a recent year. Another important diamond center is New York City; the diamond cutting process includes these steps. Diamond manufacturers analyze diamond rough from an economic perspective, with two objectives steering decisions made about how a faceted diamond will be cut; the first objective is that of maximum return on investment for the piece of diamond rough. The second is how the finished diamond can be sold. Scanning devices are used to get a 3-dimensional computer model of the rough stone. Inclusions are photographed and placed on the 3D model, used to find an optimal way to cut the stone; the process of maximizing the value of finished diamonds, from a rough diamond into a polished gemstone, is both an art and a science. The choice of cut is influenced by many factors.
Market factors include the exponential increase in value of diamonds as weight increases, referred to as weight retention, the popularity of certain shapes amongst consumers. Physical factors include the original shape of the rough stone, location of the inclusions and flaws to be eliminated; the weight retention analysis studies the diamond rough to find the best combination of finished stones as it relates to per carat value. For instance, a 2.20 carat octahedron may produce either two half carat diamonds whose combined value may be higher than that of a 0.80 carat diamond + 0.30 carat diamond that could be cut from the same rough diamond. The round brilliant cut and square brilliant cuts are preferred when the crystal is an octahedron, as two stones may be cut from one such crystal. Oddly shaped crystals, such as macles are more to be cut in a fancy cut—that is, a cut other than the round brilliant—which the particular crystal shape lends itself to. With modern techniques, the cutting and polishing of a diamond crystal always results in a dramatic loss of weight, about 50%.
Sometimes the cutters compromise and accept lesser proportions and symmetry in order to avoid inclusions or to preserve the weight. Since the per-carat price of a diamond shifts around key milestones, many one-carat diamonds are the result of compromising Cut quality for Carat weight. In colored diamonds, cutting can influence the color grade of the diamond, thereby raising its value. Certain cut shapes are used to intensify the color of the diamond; the radiant cut is an example of this type of cut. Natural green color diamonds most have a surface coloration caused by natural irradiation, which does not extend through the stone. For this reason green diamonds are cut with significant portions of the original rough diamond's surface left on the finished gem, it is these naturals. The other consideration of diamond planning is how a diamond will sell; this consideration is unique to the type of manufacturer. While a certain cutting plan may yield a better value, a different plan may yield diamonds that will sell sooner, providing an earlier return on the investment.
Cleaving is the separation of a piece of diamond rough into separate pieces, to be finished as separate gems. Sawing is the use of a diamond laser to cut the diamond rough into separate pieces. Bruting is the art of cutting a diamond round. In the modern era diamonds are rounded using either a laser. Industrial diamonds can be used for bruting a diamond round. Modern computer software measures the roundness of each diamond and "Ideal Cut" diamonds have to round within a 10th of a millimeter to qualify as an excellent cut diamond. Diamond polishing is the final polishing of the diamond. In a diamond factory one would find a diamond "Crossworker" who first places the main facets on a diamond; this is done to ensure maximum weight and best angles for the specific shape of diamond. After initial crossworking is complete, the diamond is finalized by smoothing the main facets by the crossworker, known as polishing the diamond. After the main facets have been polished by the crossworker, the final facets are polished onto the diamond by a "Brillianteer."
The facets added are the stars and bottom halves known as upper and lower girdle facets. The final stage
Christie's is a British auction house. It was founded in 1766 by James Christie, its main premises are on King Street, St James's, in London and in the Rockefeller Center in New York City. The company is owned by the holding company of François-Henri Pinault. Sales in 2015 totalled £4.8 billion. In 2017 the Salvator Mundi was sold for $450.3 million at Christie's, which at that time was the highest price paid for a single painting at an auction. The official company literature states that founder James Christie conducted the first sale in London, England, on 5 December 1766, the earliest auction catalogue the company retains is from December 1766. However, other sources note that James Christie rented auction rooms from 1762, newspaper advertisements for Christie's sales dating from 1759 have been traced. Christie's was a public company, listed on the London Stock Exchange, from 1973 to 1999. In 1974, Jo Floyd was appointed chairman of Christie's, he served as chairman of Christie's International plc from 1976 to 1988, until handing over to Lord Carrington, was a non-executive director until 1992.
Christie's International Inc. held its first sale in the United States in 1977. Christie's growth was steady since 1989, when it had 42 % of the auction market. In 1990, the company reversed a long-standing policy and guaranteed a minimum price for a collection of artworks in its May auctions. In 1996, sales exceeded those of Sotheby's for the first time since 1954. However, profits did not grow at the same pace. In 1993, Christie's paid $12.7 million for the London gallery Spink & Son, which specialised in Oriental art and British paintings. The company bought Leger Gallery for $3.3 million in 1996, merged it with Spink to become Spink-Leger. Spink-Leger closed in 2002. To make itself competitive with Sotheby's in the property market, Christie's bought Great Estates in 1995 the largest network of independent estate agents in North America, changing its name to Christie's Great Estates Inc. In December 1997, under the chairmanship of Lord Hindlip, Christie's put itself on the auction block, but after two months of negotiations with the consortium-led investment firm SBC Warburg Dillon Read it did not attract a bid high enough to accept.
In May 1998, François Pinault's holding company, Groupe Artémis S. A. first bought 29.1 percent of the company for $243.2 million, subsequently purchased the rest of it in a deal that valued the entire company at $1.2 billion. The company has since not been reporting profits, its policy, in line with UK accounting standards, is to convert non-UK results using an average exchange rate weighted daily by sales throughout the year. In 2002, Christie's France held its first auction in Paris. Like Sotheby's, Christie's became involved in high-profile private transactions. In 2006, Christie's offered a reported $21 million guarantee to the Donald Judd Foundation and displayed the artist's works for five weeks in an exhibition that won an AICA award for "Best Installation in an Alternative Space". In 2007 it brokered a $68 million deal that transferred Thomas Eakins's The Gross Clinic from the Jefferson Medical College at the Thomas Jefferson University in Philadelphia to joint ownership by the Philadelphia Museum of Art and the Pennsylvania Academy of the Fine Arts.
In the same year, the Haunch of Venison gallery became a subsidiary of the company. On 28 December 2008, The Sunday Times reported that Pinault's debts left him "considering" the sale of Christie's and that a number of "private equity groups" were thought to be interested in its acquisition. In January 2009, the company employed 2,100 people worldwide, though an unspecified number of staff and consultants were soon to be cut due to a worldwide downturn in the art market. With sales for premier Impressionist and contemporary artworks tallying only US$248.8 million in comparison to US$739 million just a year before, a second round of job cuts began after May 2009. Guy Bennett resigned just before to the beginning of the summer 2009 sales season. Although the economic downturn has encouraged some collectors to sell art, others are unwilling to sell in a market which may yield only bargain prices. On 1 January 2017, Guillaume Cerutti was appointed chief executive officer. Patricia Barbizet was appointed chief executive officer of Christie's in 2014, the first female CEO of the company.
She replaced Steven Murphy, hired in 2010 to develop their online presence and launch in new markets, such as China. In 2012, Impressionist works, which dominated the market during the 1980s boom, were replaced by contemporary art as Christie's top category. Asian art was the third most-lucrative area. With income from classic auctioneering falling, treaty sales made £413.4 million in the first half of 2012, an increase of 53% on the same period last year. The company has promoted curated events, centred on a theme rather than an art classification or time period; as part of a companywide review in 2017, Christie's announced the layoffs of 250 employees, or 12 percent of the total work force, based in Britain and Europe. From 2008 until 2013, Christie's charged 25 percent for the first $50,000. From 2013, it charged 25 percent for the first $75,000. Christie's main London salesroom is on
BBC News is an operational business division of the British Broadcasting Corporation responsible for the gathering and broadcasting of news and current affairs. The department is the world's largest broadcast news organisation and generates about 120 hours of radio and television output each day, as well as online news coverage; the service maintains 50 foreign news bureaus with more than 250 correspondents around the world. Fran Unsworth has been Director of News and Current Affairs since January 2018; the department's annual budget is in excess of £350 million. BBC News' domestic and online news divisions are housed within the largest live newsroom in Europe, in Broadcasting House in central London. Parliamentary coverage is broadcast from studios in Millbank in London. Through the BBC English Regions, the BBC has regional centres across England, as well as national news centres in Northern Ireland and Wales. All nations and English regions produce their own local news programmes and other current affairs and sport programmes.
The BBC is a quasi-autonomous corporation authorised by Royal Charter, making it operationally independent of the government, who have no power to appoint or dismiss its director-general, required to report impartially. As with all major media outlets it has been accused of political bias from across the political spectrum, both within the UK and abroad; the British Broadcasting Company broadcast its first radio bulletin from radio station.2LO In 14 November 1922. Wishing to avoid competition, newspaper publishers persuaded the government to ban the BBC from broadcasting news before 7:00 pm, to force it to use wire service copy instead of reporting on its own. On Easter weekend in 1930, this reliance on newspaper wire services left the radio news service with no information to report after saying There is no news today. Piano music was played instead; the BBC gained the right to edit the copy and, in 1934, created its own news operation. However, it could not broadcast news before 6 PM until World War II.
Gaumont British and Movietone cinema newsreels had been broadcast on the TV service since 1936, with the BBC producing its own equivalent Television Newsreel programme from January 1948. A weekly Children's Newsreel was inaugurated on 23 April 1950, to around 350,000 receivers; the network began simulcasting its radio news on television in 1946, with a still picture of Big Ben. Televised bulletins began on 5 July 1954, broadcast from leased studios within Alexandra Palace in London; the public's interest in television and live events was stimulated by Elizabeth II's coronation in 1953. It is estimated that up to 27 million people viewed the programme in the UK, overtaking radio's audience of 12 million for the first time; those live pictures were fed from 21 cameras in central London to Alexandra Palace for transmission, on to other UK transmitters opened in time for the event. That year, there were around two million TV Licences held in the UK, rising to over three million the following year, four and a half million by 1955.
Television news, although physically separate from its radio counterpart, was still under radio news' control – correspondents provided reports for both outlets–and that first bulletin, shown on 5 July 1954 on the BBC television service and presented by Richard Baker, involved his providing narration off-screen while stills were shown. This was followed by the customary Television Newsreel with a recorded commentary by John Snagge, it was revealed that this had been due to producers fearing a newsreader with visible facial movements would distract the viewer from the story. On-screen newsreaders were introduced a year in 1955 – Kenneth Kendall, Robert Dougall, Richard Baker–three weeks before ITN's launch on 21 September 1955. Mainstream television production had started to move out of Alexandra Palace in 1950 to larger premises – at Lime Grove Studios in Shepherd's Bush, west London – taking Current Affairs with it, it was from here that the first Panorama, a new documentary programme, was transmitted on 11 November 1953, with Richard Dimbleby becoming anchor in 1955.
On 18 February 1957, the topical early-evening programme Tonight, hosted by Cliff Michelmore and designed to fill the airtime provided by the abolition of the Toddlers' Truce, was broadcast from Marconi's Viking Studio in St Mary Abbott's Place, Kensington – with the programme moving into a Lime Grove studio in 1960, where it maintained its production office. On 28 October 1957, the Today programme, a morning radio programme, was launched in central London on the Home Service. In 1958, Hugh Carleton Greene became head of Current Affairs, he set up a BBC study group whose findings, published in 1959, were critical of what the television news operation had become under his predecessor, Tahu Hole. The report proposed that the head of television news should take control, that the television service should have a proper newsroom of its own, with an editor-of-the-day. On 1 January 1960, Greene became Director-General and brought about big changes at BBC Television and BBC Television News. BBC Television News had been created in 1955, in response to the founding of ITN.
The changes made by Greene were aimed at making BBC reporting more similar to ITN, rated by study groups held by Greene. A newsroom was created at Alexandra Palace, television reporters were recruited and given the opportunity to write and voice their own scripts–without the "impossible burden" of having to cover stories for radio too. In 1987 thirty years John B
Australian Associated Press
Australian Associated Press is an Australian news agency. The organisation was established in 1935 by Keith Murdoch. AAP employs more than 175 journalists who work in bureaus in all Australian territories, its NZ Newswire division includes reporters in Wellington. It maintains correspondents in Port Moresby, London and Los Angeles as well as using a network of contributors from the US, Europe and Africa. AAP's domestic news coverage is complemented by alliances with the major international news agencies. AAP is owned by three Australian news organisations – News Corp Australia and Seven West Media. Fairfax owns 47%, News owns 45%, Seven West 8%. Together these companies produce the vast majority of Australian newspapers. AAP's main focus is on breaking news, but it distributes'soft' news, colour stories, feature stories, filler material and photographs; the editor-in-chief is Tony Gillies. In the 1990s, AAP's telecommunications division was spun off as a telco, AAPT, sold to Telecom New Zealand in 2000.
It was sold again to TPG Telecom in 2013. News agency Media in Australia Australian Associated Press Australian Communications and Media Authority