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Deepdene (diamond)
The Deepdene is a yellow diamond widely considered to be the largest irradiated diamond in the world. Origin of the name The Deepdene gets its name from the Pennsylvania estate of Margaret Adams Plummer, wife of Cary W. Bok, both the diamond's original owners. At the time, the Deepdene weighed slightly more at and was mounted in a diamond clip. Harry Winston bought the diamond from the Boks in 1954 and it eventually found its way to a London firm in 1960 and later to a German owner. Irradiation scandal On 27 May 1971, Christie's auction house in Geneva offered to prospective buyers the cushion-cut, fancy golden-yellow diamond which would only later come to be known as the "Deepdene." Its clarity was stated as VVS1 (with two very small imperfections near the girdle or midsection of the stone) and its vivid-yellow colour was guaranteed to be natural by both the German gemological institute and the University of Mainz. However, Dr. Eduard Gübelin, the founder of Gübe ...
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Premier Mine
The Premier Mine is an underground diamond mine owned by Petra Diamonds in the town of Cullinan, east of Pretoria, Gauteng Province, South Africa. Established in 1902, it was renamed the Cullinan Diamond Mine in November 2003 in celebration of its centenary. The mine is a carrot-shaped volcanic pipe and has a surface area of . The mine rose to prominence in 1905, when the Cullinan Diamond – the largest rough diamond of gem quality ever found – was discovered there. The mine has produced over 750 stones that are greater than and more than a quarter of all the world's diamonds that are greater than . It is also the only significant source of blue diamonds in the world. Notable discoveries The Cullinan Diamond is the largest rough gem-quality diamond ever found, at . It was found by Frederick Wells, surface manager of the Premier Diamond Mining Company in Cullinan, Gauteng, South Africa, on 25 January 1905. The stone was named after Sir Thomas Cullinan, the owner of th ...
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Neutron
The neutron is a subatomic particle, symbol or , which has a neutral (not positive or negative) charge, and a mass slightly greater than that of a proton. Protons and neutrons constitute the nuclei of atoms. Since protons and neutrons behave similarly within the nucleus, and each has a mass of approximately one atomic mass unit, they are both referred to as nucleons. Their properties and interactions are described by nuclear physics. Protons and neutrons are not elementary particles; each is composed of three quarks. The chemical properties of an atom are mostly determined by the configuration of electrons that orbit the atom's heavy nucleus. The electron configuration is determined by the charge of the nucleus, which is determined by the number of protons, or atomic number. The number of neutrons is the neutron number. Neutrons do not affect the electron configuration, but the sum of atomic and neutron numbers is the mass of the nucleus. Atoms of a chemical element t ...
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Yellow Diamonds
Yellow is the color between green and orange on the spectrum of light. It is evoked by light with a dominant wavelength of roughly 575585 nm. It is a primary color in subtractive color systems, used in painting or color printing. In the RGB color model, used to create colors on television and computer screens, yellow is a secondary color made by combining red and green at equal intensity. Carotenoids give the characteristic yellow color to autumn leaves, corn, canaries, daffodils, and lemons, as well as egg yolks, buttercups, and bananas. They absorb light energy and protect plants from photo damage in some cases. Sunlight has a slight yellowish hue when the Sun is near the horizon, due to atmospheric scattering of shorter wavelengths (green, blue, and violet). Because it was widely available, yellow ochre pigment was one of the first colors used in art; the Lascaux cave in France has a painting of a yellow horse 17,000 years old. Ochre and orpiment pigments were used t ...
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List Of Diamonds
Diamond (gemstone), Diamonds become famous typically for some combination of their size, color and quality. Diamonds occur naturally in many different colors, so the largest diamond of a particular color may not be large in absolute terms, but it may still be considered very desirable. Diamonds may also have high valuations or sale prices, or go on to have a noteworthy ownership history, but this will tend to occur for diamonds that had some outstanding characteristic to begin with. As new diamonds are discovered, the uniqueness of existing ones may diminish and there is no agreed-upon measure of a large or a high-quality diamond, so a strict inclusion criteria for notable diamonds is not attainable. Diamond A diamond is a Allotropes of carbon, solid form of the element carbon with its atoms arranged in a crystal structure called diamond cubic. At Standard conditions for temperature and pressure, room temperature and pressure, another solid form of carbon known as graphite is the ...
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Culet
{{inline, date=November 2022 In gemology, a culet is a flat face on the bottom of a gemstone. During the 14th century, after the adoption of the table cut, a further facet was added to the bottom of the cut parallel to the surface of the table. The term used for these bottom facets derives from the Latin word for bottom, ''culus''. The culet is added largely to protect the integrity of the gemstone. On a diamond, the cleavage plane runs parallel to the octahedral faces, and so any damage to the tip of the diamond could cause a split up the entire length of the pavilion. With other gemstones that are not subject to cleavage, the culet is added to protect the fragility of the pointed tip. The culet has remained optional on many diamond cuts up to the present day, and was omitted from Marcel Tolkowsky's original designs for the round brilliant A brilliant is a diamond or other gemstone cut in a particular form with numerous facets so as to have exceptional brilliance. T ...
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Danielle Steel
Danielle Fernandes Dominique Schuelein-Steel (born August 14, 1947) is an American writer, best known for her romance novels. She is the bestselling author alive and the fourth-bestselling fiction author of all time, with over 800 million copies sold. As of 2021, she has written 190 books, including over 140 novels. Based in California for most of her career, Steel has produced several books a year, often juggling up to five projects at once. All of her novels have been bestsellers, including those issued in hardback, despite "a resounding lack of critical acclaim" (''Publishers Weekly''). Her books often involve rich families facing a crisis, threatened by dark elements such as prison, fraud, blackmail and suicide. Steel has also published children's fiction and poetry, as well as creating a foundation that funds mental illness related organizations. Her books have been translated into 43 languages, with 22 adapted for television, including two that have received Golden G ...
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Graff Diamonds
Graff is a British multinational jeweller based in London. It was founded by British jeweller Laurence Graff in 1960. A vertically integrated company, Graff operations comprise the design, manufacture and retail distribution of jewellery and watches. History Graff was founded in London in 1960 by Laurence Graff. Awards Graff were the first ever jewellers to receive the Queen's Award for Industry and Export (now known as the Queen's Award for Enterprise), awarded in 1973. Since then, the company has received this award a further four times, most recently in 2014. The Queen's Award to Industry and Export award is considered to be the highest accolade for a British company. It is awarded on the advice of the Prime Minister, following thorough examinations of each application by an Advisory Committee formed of leading representatives of industry and commerce. Sourcing Graff adheres to the Kimberley Process, never knowingly buying or trading rough diamonds from areas where this woul ...
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Lawrence Graff
Laurence Graff (born 13 June 1938) is an English jeweller and billionaire businessman, best known as the founder of Graff Diamonds, supplier of jewellery and jewels. Early life Graff was born in Stepney in 1938 into a Jewish family, the son of a Romanian mother, Rebecca Segal, and a Russian father, Harry Graff. His brother Raymond was born in 1947. Career Graff left school and became an apprentice when he was 14. He soon went into partnership with Schindler, a jeweller, repairing rings and creating small pieces of jewellery in a small shop. That shop went out of business and so Graff began selling his jewellery designs independently to jewellers all over England. By 1962, he had two jewellery shops, including his first in Hatton Garden. In 1960, he founded the Graff Diamonds company. In 1966 he commissioned the English jewellery-designer Robert Thomas to design a diamond jewel to enter into the De Beers Diamond International Awards competition. The ribbon bracelet created won ...
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Spectrum Analyzer
A spectrum analyzer measures the magnitude of an input signal versus frequency within the full frequency range of the instrument. The primary use is to measure the power of the spectrum of known and unknown signals. The input signal that most common spectrum analyzers measure is electrical; however, spectral compositions of other signals, such as acoustic pressure waves and optical light waves, can be considered through the use of an appropriate transducer. Spectrum analyzers for other types of signals also exist, such as optical spectrum analyzers which use direct optical techniques such as a monochromator to make measurements. By analyzing the spectra of electrical signals, dominant frequency, power, distortion, harmonics, bandwidth, and other spectral components of a signal can be observed that are not easily detectable in time domain waveforms. These parameters are useful in the characterization of electronic devices, such as wireless transmitters. The display of a spectru ...
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Basil Anderson
Basil (, ; ''Ocimum basilicum'' , also called great basil, is a culinary herb of the family Lamiaceae (mints). It is a tender plant, and is used in cuisines worldwide. In Western cuisine, the generic term "basil" refers to the variety also known as sweet basil or Genovese basil. Basil is native to tropical regions from Central Africa to Southeast Asia. In temperate climates basil is treated as an annual plant, however, basil can be grown as a short-lived perennial or biennial in warmer horticultural zones with tropical or Mediterranean climates. There are many varieties of basil including sweet basil, Thai basil (''O. basilicum'' var. ''thyrsiflora''), and Mrs. Burns' Lemon (''O. basilicum var. citriodora''). ''O. basilicum'' can cross-pollinate with other species of the ''Ocimum'' genus, producing hybrids such as lemon basil (''O. × citriodorum'') and African blue basil (''O. × kilimandscharicum''). Etymology The name "basil" comes from the Latin , and the Greek (), m ...
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London
London is the capital and largest city of England and the United Kingdom, with a population of just under 9 million. It stands on the River Thames in south-east England at the head of a estuary down to the North Sea, and has been a major settlement for two millennia. The City of London, its ancient core and financial centre, was founded by the Romans as '' Londinium'' and retains its medieval boundaries.See also: Independent city § National capitals The City of Westminster, to the west of the City of London, has for centuries hosted the national government and parliament. Since the 19th century, the name "London" has also referred to the metropolis around this core, historically split between the counties of Middlesex, Essex, Surrey, Kent, and Hertfordshire, which largely comprises Greater London, governed by the Greater London Authority.The Greater London Authority consists of the Mayor of London and the London Assembly. The London Mayor is distinguished fr ...
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Van Cleef & Arpels
Van Cleef & Arpels is a French high-end luxury jewelry company. It was founded in 1896 by the Dutch diamond-cutter Alfred Van Cleef and his father-in-law Salomon Arpels in Paris. Their pieces often feature flowers, animals, and fairies, and have been worn by style icons and royalty such as Grace Kelly, the Princess of Wales, Ava Gardner, Farah Pahlavi, Eva Perón, Elizabeth Taylor, the Duchess of Windsor and Queen Nazli of Egypt. History The Dutch diamond-cutter Alfred Van Cleef and his father-in-law, Salomon Arpels, founded the company in 1896. In 1906, following Arpels’s death, Alfred and two of his brothers-in-law, Charles and Julien, acquired space for Van Cleef & Arpels at 22 Place Vendôme, across from the Hôtel Ritz, where Van Cleef & Arpels opened its first boutique shop. The third Arpels brother, Louis Arpels, joined the company in 1913. Van Cleef & Arpels opened boutiques in holiday resorts such as Deauville, Vichy, Le Touquet, Nice, and Monte-Carlo. In 1925, ...
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