1.
Diamond
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Diamond is a metastable allotrope of carbon, where the carbon atoms are arranged in a variation of the face-centered cubic crystal structure called a diamond lattice. Diamond is less stable than graphite, but the rate from diamond to graphite is negligible at standard conditions. Diamond is renowned as a material with superlative physical qualities, most of which originate from the covalent bonding between its atoms. In particular, diamond has the highest hardness and thermal conductivity of any bulk material and those properties determine the major industrial application of diamond in cutting and polishing tools and the scientific applications in diamond knives and diamond anvil cells. Because of its extremely rigid lattice, it can be contaminated by very few types of impurities, such as boron, small amounts of defects or impurities color diamond blue, yellow, brown, green, purple, pink, orange or red. Diamond also has relatively high optical dispersion, most natural diamonds are formed at high temperature and pressure at depths of 140 to 190 kilometers in the Earths mantle. Carbon-containing minerals provide the source, and the growth occurs over periods from 1 billion to 3.3 billion years. Diamonds are brought close to the Earths surface through deep volcanic eruptions by magma, Diamonds can also be produced synthetically in a HPHT method which approximately simulates the conditions in the Earths mantle. An alternative, and completely different growth technique is chemical vapor deposition, several non-diamond materials, which include cubic zirconia and silicon carbide and are often called diamond simulants, resemble diamond in appearance and many properties. Special gemological techniques have developed to distinguish natural diamonds, synthetic diamonds. The word is from the ancient Greek ἀδάμας – adámas unbreakable, the name diamond is derived from the ancient Greek αδάμας, proper, unalterable, unbreakable, untamed, from ἀ-, un- + δαμάω, I overpower, I tame. Diamonds have been known in India for at least 3,000 years, Diamonds have been treasured as gemstones since their use as religious icons in ancient India. Their usage in engraving tools also dates to early human history, later in 1797, the English chemist Smithson Tennant repeated and expanded that experiment. By demonstrating that burning diamond and graphite releases the same amount of gas, the most familiar uses of diamonds today are as gemstones used for adornment, a use which dates back into antiquity, and as industrial abrasives for cutting hard materials. The dispersion of light into spectral colors is the primary gemological characteristic of gem diamonds. In the 20th century, experts in gemology developed methods of grading diamonds, four characteristics, known informally as the four Cs, are now commonly used as the basic descriptors of diamonds, these are carat, cut, color, and clarity. A large, flawless diamond is known as a paragon and these conditions are met in two places on Earth, in the lithospheric mantle below relatively stable continental plates, and at the site of a meteorite strike. The conditions for diamond formation to happen in the mantle occur at considerable depth corresponding to the requirements of temperature and pressure
2.
Material properties of diamond
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Diamond is the allotrope of carbon in which the carbon atoms are arranged in the specific type of cubic lattice called diamond cubic. Diamond is an isotropic crystal that is transparent to opaque. Owing to its strong covalent bonding, diamond is the hardest naturally occurring material known, yet, due to important structural weaknesses, diamonds toughness is only fair to good. The precise tensile strength of diamond is unknown, however strength up to 60 GPa has been observed, the anisotropy of diamond hardness is carefully considered during diamond cutting. Diamond has a refractive index and moderate dispersion properties which give cut diamonds their brilliance. Scientists classify diamonds into four types according to the nature of crystallographic defects present. Trace impurities substitutionally replacing carbon atoms in a crystal structure. Most diamonds are electrical insulators but extremely efficient thermal conductors, unlike many other minerals, the specific gravity of diamond crystals has rather small variation from diamond to diamond. Known to the ancient Greeks as ἀδάμας – adámas and sometimes called adamant, diamond is the hardest known naturally occurring material, Diamond is extremely strong owing to the structure of its carbon atoms, where each carbon atom has four neighbors joined to it with covalent bonds. It has been shown that some diamond aggregates having nanometer grain size are harder and tougher than conventional large diamond crystals, owing to the use of those new ultra-hard materials for diamond testing, more accurate values are now known for diamond hardness. Because the test only works properly with a tip made of material than the sample being tested. Diamond also has one of the smallest compressibilities of any material, similarly, diamonds hardness is markedly directional, the hardest direction is the diagonal on the cube face,100 times harder than the softest direction, which is the dodecahedral plane. The octahedral plane is intermediate between the two extremes, the diamond cutting process relies heavily on this directional hardness, as without it a diamond would be nearly impossible to fashion. Cleavage also plays a role, especially in large stones where the cutter wishes to remove flawed material or to produce more than one stone from the same piece of rough. Diamonds crystallize in the cubic crystal system and consist of tetrahedrally, covalently bonded carbon atoms. A second form called lonsdaleite, with symmetry, has also been found. The local environment of each atom is identical in the two structures, from theoretical considerations, lonsdaleite is expected to be harder than diamond, but the size and quality of the available stones are insufficient to test this hypothesis. In terms of crystal habit, diamonds occur most often as euhedral or rounded octahedra, other forms include dodecahedra and cubes
3.
Crystallographic defects in diamond
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Imperfections in the crystal lattice of diamond are common. Such crystallographic defects in diamond may be the result of irregularities or extrinsic substitutional or interstitial impurities. Absorption spectrum is used not only to identify the defects, but also to estimate their concentration, there is a tradition in diamond spectroscopy to label a defect-induced spectrum by a numbered acronym. This tradition has been followed in general with some notable deviations, many acronyms are confusing though, Some symbols are too similar. Accidentally, same labels were given to different centers detected by EPR, whereas some acronyms are logical, such as N3 or H3, many are not. In particular, there is no distinction between the meaning of labels GR, R and TR. The symmetry of defects in crystals is described by the point groups and they differ from the space groups describing the symmetry of crystals by absence of translations, and thus are much fewer in number. In diamond, only defects of the following symmetries have been observed thus far, tetrahedral, tetragonal, trigonal, the defect symmetry allows predicting many optical properties. For example, one-phonon absorption in pure diamond lattice is forbidden because the lattice has an inversion center, however, introducing any defect breaks the crystal symmetry resulting in defect-induced infrared absorption, which is the most common tool to measure the defect concentrations in diamond. In synthetic diamond grown by the high-pressure high-temperature synthesis or chemical vapor deposition, such alignment has been also been observed in gallium arsenide and thus is not unique to diamond. Various elemental analyses of diamond reveal a range of impurities. They mostly originate, however, from inclusions of foreign materials in diamond, also, virtually any element can be hammered into diamond by ion implantation. More essential are elements which can be introduced into the lattice as isolated atoms during the diamond growth. By 2008, those elements are nitrogen, boron, hydrogen, silicon, phosphorus, nickel, cobalt, manganese and tungsten have been unambiguously detected in diamond, but they might originate from foreign inclusions. Detection of isolated iron in diamond has later been re-interpreted in terms of micro-particles of ruby produced during the diamond synthesis, oxygen is believed to be a major impurity in diamond, but it has not been spectroscopically identified in diamond yet. Two electron paramagnetic resonance centers have been assigned to nitrogen–oxygen complexes, however, the assignment is indirect and the corresponding concentrations are rather low. The most common impurity in diamond is nitrogen, which can comprise up to 1% of a diamond by mass. Previously, all defects in diamond were thought to be the result of structural anomalies, later research revealed nitrogen to be present in most diamonds
4.
Diamond color
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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 diamonds coloration, a 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 naturally colored diamonds, including red diamonds. Diamonds occur in a variety of colors—steel gray, white, blue, yellow, orange, red, green, pink to purple, brown, colored diamonds contain interstitial impurities or structural defects that cause the coloration, whilst pure diamonds are perfectly transparent and colorless. 1%. If the nitrogen atoms are in pairs they do not affect the diamonds color, if the nitrogen atoms are in large even-numbered aggregates they impart a yellow to brown tint. 1% of known natural diamonds. Synthetic diamond containing nitrogen is Type Ib, Type I diamonds absorb in both the infrared and ultraviolet region, from 320 nm. They also 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 and they also have differing fluorescence characteristics, but no discernible visible absorption spectrum. 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 also occur in Type Ia diamonds, also 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 deformation of the crystal lattice from temperature and pressure. Black diamonds are caused by 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 crystal lattice distortion, the majority of diamonds that are mined are in a range of pale yellow or brown color that is termed the normal color range. Diamonds that are of yellow or brown, or any other color are called fancy color diamonds. Diamonds that are of the very highest purity are totally colorless, the degree to which diamonds exhibit body color is one of the four value factors by which diamonds are assessed
5.
Diamond cut
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A diamond cut is a style or design guide used when shaping a diamond for polishing such as the brilliant cut. Cut does not refer to shape, but the symmetry, proportioning, the cut of a diamond greatly affects a diamonds brilliance, this means if it is cut poorly, it will be less luminous. In order to best use a diamond gemstones material properties, a number of different diamond cuts have been developed, a diamond cut constitutes a more or less symmetrical arrangement of facets, which together modify the shape and appearance of a diamond crystal. Diamond cutters must consider several factors, such as the shape and size of the crystal, the practical history of diamond cuts can be traced back to the Middle Ages, while their theoretical basis was not developed until the turn of the 20th century. The most popular of diamond cuts is the round brilliant, whose facet arrangements. Also popular are the cuts, which come in a variety of shapes—many of which were derived from the round brilliant. A diamonds cut is evaluated by trained graders, with higher grades given to stones whose symmetry, the strictest standards are applied to the round brilliant, although its facet count is invariable, its proportions are not. Different countries base their cut grading on different ideals, one may speak of the American Standard or the Scandinavian Standard, to give but two examples. The history of diamond cuts can be traced to the late Middle Ages and this was called the point cut and dates from the mid 14th century, by 1375 there was a guild of diamond polishers at Nürnberg. By the mid 15th century, the point cut began to be improved upon, the importance of a culet was also realised, and some table-cut stones may possess one. The addition of four corner facets created the old single cut, neither of these early cuts would reveal what diamond is prized for today, its strong dispersion or fire. At the time, diamond was valued chiefly for its lustre and superlative hardness. For this reason, colored gemstones such as ruby and sapphire were far more popular in jewelry of the era. In or around 1476, Lodewyk van Berquem, a Flemish polisher of Bruges, introduced the technique of absolute symmetry in the disposition of facets using a device of his own invention, the scaif. He cut stones in the known as pendeloque or briolette. However, Indian rose cuts were far less symmetrical as their cutters had the primary interest of conserving carat weight, in either event, the rose cut continued to evolve, with its depth, number and arrangements of facets being tweaked. The first brilliant cuts were introduced in the middle of the 17th century, known as Mazarins, they had 17 facets on the crown. They are also called double-cut brilliants as they are seen as a step up from old single cuts, yet Peruzzi-cut diamonds, when seen nowadays, seem exceedingly dull compared to modern-cut brilliants
6.
Diamond cutting
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Diamond cutting is the practice of changing a diamond from a rough stone into a faceted gem. Cutting diamond requires specialized knowledge, tools, equipment, and techniques because of its extreme difficulty, the first guild of diamond cutters and polishers was formed in 1375 in Nuremberg, Germany, and led to the development of various types of cut. This has two meanings in relation to diamonds, the first is the shape, square, oval, and so on. The second relates to the quality of cut within the shape. Since diamonds are one of the hardest materials, special diamond-coated surfaces are used to grind the diamond down, 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, and Dubai from where roughs are sent to the processing centers of India. Diamonds are cut and polished in Surat, India and the Chinese cities of Guangzhou, 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, planning, cleaving or sawing, bruting, polishing, and final inspection. Diamond manufacturers analyze diamond rough from a perspective, with two objectives steering decisions made about how a faceted diamond will be cut. The first objective is that of return on investment for the piece of diamond rough. The second is how quickly the finished diamond can be sold, scanning devices are used to get a 3-dimensional computer model of the rough stone. Also, inclusions are photographed and placed on the 3D model, 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, and the popularity of certain shapes amongst consumers. Physical factors include the shape of the rough stone, and location of the inclusions. The weight retention analysis studies the diamond rough to find the best combination of finished stones as it relates to per carat value. The round brilliant cut and square brilliant cuts are preferred when the crystal is an octahedron, oddly shaped crystals, such as macles are more likely to be cut in a fancy cut—that is, a cut other than the round brilliant—which the particular crystal shape lends itself to. Even with modern techniques, the cutting and polishing of a diamond crystal always results in a loss of weight. 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
7.
Synthetic diamond
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A synthetic diamond is diamond produced in an artificial process, as opposed to natural diamonds, which are created by geological processes. Synthetic diamond is widely known as HPHT diamond or CVD diamond after the two common production methods. While the term synthetic is associated by consumers with imitation products, in the U. S. the Federal Trade Commission has indicated that the alternative terms laboratory-grown, laboratory-created, and -created would more clearly communicate the nature of the stone. Numerous claims of diamond synthesis were documented between 1879 and 1928, most of those attempts were carefully analyzed but none were confirmed, in the 1940s, systematic research began in the United States, Sweden and the Soviet Union to grow diamonds using CVD and HPHT processes. The first reproducible synthesis was reported around 1953 and those two processes still dominate the production of synthetic diamond. A third method, known as detonation synthesis, entered the market in the late 1990s. In this process, nanometer-sized diamond grains are created in a detonation of carbon-containing explosives, a fourth method, treating graphite with high-power ultrasound, has been demonstrated in the laboratory, but currently has no commercial application. Synthetic diamond is used in abrasives, in cutting and polishing tools. Electronic applications of synthetic diamond are being developed, including high-power switches at power stations, high-frequency field-effect transistors, synthetic diamond detectors of ultraviolet light or high-energy particles are used at high-energy research facilities and are available commercially. It is estimated that 98% of industrial grade diamond demand is supplied with synthetic diamonds, both CVD and HPHT diamonds can be cut into gems and various colors can be produced, clear white, yellow, brown, blue, green and orange. After the 1797 discovery that diamond was pure carbon, many attempts were made to convert various forms of carbon into diamond. The earliest successes were reported by James Ballantyne Hannay in 1879 and their method involved heating charcoal at up to 3500 °C with iron inside a carbon crucible in a furnace. Whereas Hannay used a tube, Moissan applied his newly developed electric arc furnace. The molten iron was then cooled by immersion in water. The contraction generated by the cooling supposedly produced the pressure required to transform graphite into diamond. Moissan published his work in a series of articles in the 1890s, Many other scientists tried to replicate his experiments. Sir William Crookes claimed success in 1909, otto Ruff claimed in 1917 to have produced diamonds up to 7 mm in diameter, but later retracted his statement. In 1926, Dr. J Willard Hershey of McPherson College replicated Moissans and Ruffs experiments, producing a synthetic diamond, despite the claims of Moissan, Ruff, and Hershey, other experimenters were unable to reproduce their synthesis
8.
Blood diamond
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Blood diamonds is a term used for a diamond mined in a war zone and sold to finance an insurgency, an invading armys war efforts, or a warlords activity. The term is used to highlight the consequences of the diamond trade in certain areas. Diamonds mined during the recent civil wars in Angola, Ivory Coast, Sierra Leone, the term conflict resource refers to analogous situations involving other natural resources. Reports estimated that as much as 20% of the production in the 1980s was being sold for illegal and unethical purposes. By 1999, the diamond trade was estimated by the World Diamond Council to have been reduced to 3. 06% of the worlds diamond production. The World Diamond Council reported that by 2004 this percentage had fallen to approximately 1%, despite the UN Resolution, UNITA was able to continue to sell or trade some diamonds in order to finance its war effort. The UN set out to find how this remaining illicit trade was being conducted and appointed Canadian ambassador Robert Fowler to investigate, in 2000, he produced the Fowler Report, which named those countries, organizations and individuals involved in the trade. Ivory Coast began to develop a diamond mining industry in the early 1990s. A coup overthrew the government in 1999, starting a civil war, the country became a route for exporting diamonds from Liberia and war-torn Sierra Leone. Foreign investment began to withdraw from Ivory Coast, to curtail the illegal trade, the nation stopped all diamond mining and the UN Security Council banned all exports of diamonds from Ivory Coast in December 2005. Despite UN sanctions the illicit diamond trade still exists in Ivory Coast, the Democratic Republic of the Congo has suffered numerous looting wars in the 1990s, but has become a member of the Kimberley Process and now exports about 8% of the worlds diamonds. From 1989 to 2003, Liberia was engaged in a civil war, in 2000, the UN accused Liberian president Charles G. Taylor of supporting the Revolutionary United Front insurgency in neighboring Sierra Leone with weapons and training in exchange for diamonds. In 2001, the United Nations applied sanctions on the Liberian diamond trade, in August 2003, Taylor stepped down as president and, after being exiled to Nigeria, faced trial in The Hague. On July 21,2006 he pleaded not guilty to crimes against humanity and war crimes, on May 30,2012, he began a 50-year sentence in a high security prison in the United Kingdom. Around the time of the 1998 United States embassy bombings, al-Qaeda allegedly bought gems from Liberia as some of its financial assets were frozen. Having regained peace, Liberia is attempting to construct a diamond mining industry. The UN has lifted sanctions and Liberia is now a member of the Kimberley Process. In December 2014 however, Liberian diamonds were reported to be produced using child labor according to the U. S. Department of Labors List of Goods Produced by Child Labor or Forced Labor
9.
De Beers
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The De Beers Group of Companies has a leading role in the diamond exploration, diamond mining, diamond retail, diamond trading and industrial diamond manufacturing sectors. The company is active in open-pit, large-scale alluvial, coastal. The company operates in 28 countries and mining takes place in Botswana, Namibia, South Africa, until the start of the 21st century, De Beers effectively had total control over the diamond market as both a monopoly and monopsony of diamonds. The company was founded in 1888 by British businessman Cecil Rhodes, who was financed by the South African diamond magnate Alfred Beit and the London-based N M Rothschild & Sons bank. In 1926, Ernest Oppenheimer, a German immigrant to Britain who had earlier founded mining giant Anglo American plc with American financier J. P. Morgan, was elected to the board of De Beers. He built and consolidated the companys global monopoly over the industry until his death in 1957. After they discovered diamonds on their land, the demands of the British government forced them to sell their farm on July 31,1871. Vooruitzicht would become the site of the Big Hole and the De Beer Mine and their name, which was given to one of the mines, subsequently became associated with the company. He invested the profits of this operation into buying up claims of small mining operators and he soon secured funding from the Rothschild family, who would finance his business expansion. The agreement soon proved to be very successful — for example during the slump of 1891–1892. The Second Boer War proved to be a time for the company. Kimberley was besieged as soon as war broke out, thereby threatening the companys valuable mines, in 1898, diamonds were discovered on farms near Pretoria, Transvaal. One led to the discovery of the Premier Mine, the Premier Mine was registered in 1902 and the Cullinan Diamond, the largest rough diamond ever discovered, was found there in 1905. However, its owner refused to join the De Beers cartel, instead, the mine started selling to a pair of independent dealers named Bernhard and Ernest Oppenheimer, thereby weakening the De Beers cartel. Francis Oats, who became chairman of De Beers in 1908, was dismissive of the threats from the Premier Mine, however, production soon equalled all of the De Beers mines combined. Ernest Oppenheimer was appointed the agent for the powerful London Syndicate. During World War I, the Premier Mine was finally absorbed into De Beers, when Rhodes died in 1902, De Beers controlled 90% of the worlds diamond production. Ernest Oppenheimer took over the chairmanship of the company in 1929, after buying shares, Oppenheimer was very concerned about the discovery of diamonds in 1908 in German South West Africa, fearing that the increased supply would swamp the market and force prices down
10.
Diamond (gemstone)
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A diamond is one of the best-known and most sought-after gemstones. Diamonds have been known to mankind and used as decorative items since ancient times, the hardness of diamond and its high dispersion of light—giving the diamond its characteristic fire—make it useful for industrial applications and desirable as jewelry. Diamonds are such a highly traded commodity that multiple organizations have created for grading and certifying them based on the four Cs, which are color, cut, clarity. Other characteristics, such as presence or lack of fluorescence, also affect the desirability, the most famous use of the diamond in jewelry is in engagement rings. The practice is documented among European aristocracy as early as the 15th century, though ruby, the modern popularity of diamonds was largely created by De Beers Consolidated Mines Ltd. which established the first large-scale diamonds mines in South Africa. Through an advertising campaign beginning in the 1930s and continuing into the century, De Beers made diamonds into a key part of the betrothal process. The diamonds high value has been the force behind dictators and revolutionary entities, especially in Africa, using slave. The value of diamonds is attributed largely to the tight control over this supply. Early references to diamonds in India come from Sanskrit texts, the Arthashastra of Kautilya mentions diamond trade in India. Buddhist works dating from the 4th century BC describe the diamond as a well-known and precious stone, golconda served as an important center for diamonds in central India. Diamonds were traded to both the east and west of India and were recognized by various cultures for their gemological or industrial uses. In his work Naturalis Historia, the Roman writer Pliny the Elder noted diamonds ornamental uses, diamonds eventually spread throughout the world, even though India had remained the only major source of the gemstone until the discovery of diamonds in Brazil in 1725. A Chinese work from the 3rd century BC mentions, Foreigners wear it in the belief that it can ward off evil influences. The Chinese, who did not find diamonds in their country, initially did not use diamond as a jewel, diamonds reached ancient Rome from India. Diamonds were also discovered in 700 AD in Borneo, and were used by the traders of southeast Asia, the modern era of diamond mining began in the 1860s in Kimberley, South Africa with the opening of the first large-scale diamond mine. The first diamond there was found in 1866 on the banks of the Orange River, in 1869, an even larger 83.50 carat diamond was found on the slopes of Colesberg Kopje on the farm Vooruitzigt belonging to the De Beers brothers. This sparked off the famous New Rush and within a month,800 claims were cut into the hillock which were worked frenetically by two to three thousand men, as the land was lowered so the hillock became a mine—in time, the world-renowned Kimberley Mine. Following agreement by the British government on compensation to the Orange Free State for its land claims
11.
Diamond simulant
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Cubic zirconia is the cubic crystalline form of zirconium dioxide. The synthesized material is hard, optically flawless and usually colorless and it should not be confused with zircon, which is a zirconium silicate. It is sometimes erroneously called cubic zirconium and its main competitor as a synthetic gemstone is a more recently cultivated material, synthetic moissanite. Cubic zirconia is crystallographically isometric, an important attribute of a diamond simulant. During synthesis zirconium oxide would naturally form monoclinic crystals, its stable form under normal atmospheric conditions, therefore, the physical and optical properties of synthesized CZ vary, all values being ranges. It is a substance, with a specific gravity between 5.6 and 6.0 — at least 1.6 times that of diamond. Cubic zirconia is relatively hard, 8–8.5 on the Mohs scale— slightly harder than most semi-precious natural gems and its refractive index is high at 2. 15–2.18 and its luster is adamantine. Its dispersion is very high at 0. 058–0.066, Cubic zirconia has no cleavage and exhibits a conchoidal fracture. Because of its hardness, it is generally considered brittle. Under shortwave UV cubic zirconia typically fluoresces a yellow, greenish yellow or beige, under longwave UV the effect is greatly diminished, with a whitish glow sometimes being seen. Colored stones may show a strong, complex rare earth absorption spectrum, discovered in 1892, the yellowish monoclinic mineral baddeleyite is a natural form of zirconium oxide. The high melting point of zirconia hinders controlled growth of single crystals, however, stabilization of cubic zirconium oxide had been realized early on, with the synthetic product stabilized zirconia introduced in 1929. Although cubic, it was in the form of a ceramic, it was used as a refractory material. In 1937, German mineralogists M. V. Stackelberg and K. Chudoba discovered naturally occurring cubic zirconia in the form of microscopic grains included in metamict zircon. This was thought to be a byproduct of the metamictization process, the discovery was confirmed through X-ray diffraction, proving the existence of a natural counterpart to the synthetic product. Its production eventually exceeded that of earlier synthetics, such as strontium titanate, synthetic rutile, YAG. Some of the earliest research into controlled single-crystal growth of cubic zirconia occurred in 1960s France, though promising, these attempts yielded only small crystals. Later, Soviet scientists under V. V. Osiko at the Lebedev Physical Institute in Moscow perfected the technique and they named the jewel Fianit after the institutes name FIAN, but the name was not used outside of the USSR
12.
Diamond enhancement
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Diamond enhancements are specific treatments, performed on natural diamonds, which are designed to improve the visual gemological characteristics of the diamond in one or more ways. The CIBJO and government agencies such as the United States Federal Trade Commission explicitly require the disclosure of all diamond treatments at the time of sale, clarity and color enhanced diamonds sell at lower price points when compared to similar, untreated diamonds. This is because enhanced diamonds are originally lower quality before the enhancement is performed, after enhancement, the diamonds may visually appear as good as their non-enhanced counterparts. Therefore, treated diamonds appear to have a greater value than they would before treatment, the clarity, or purity, of a diamond refers to internal inclusions of the diamond, and is one of the 4-Cs in determining a diamonds value. Diamonds may also have other inclusions such as air bubbles and mineral deposits such as iron or garnet, the size, color, and position of the inclusions are factors in determining the value of a diamond, especially when the other gemological characteristics are of a higher standard. The development of drilling techniques have increased the ability to selectively target, remove. The laser drilling process involves the use of a laser to bore very fine holes into a diamond to create a route of access to a black carbon crystal inclusion. The laser then burns a narrow tube or channel to the inclusion, once the location of included black carbon crystal has been reached by the drill channel, the diamond is soaked in sulfuric acid to dissolve the black carbon crystal. After soaking in sulfuric acid the black carbon crystal will dissolve and become transparent, under microscopic inspection the fine drill or bore holes can be seen, but are not distracting and do not affect sparkle or brilliance of the diamond. The channels are microscopic so that dirt or debris cannot travel down the channel and this technology became available roughly 20 years after the time the laser drilling technique was developed. Simply put, fracture filling makes tiny natural fractures inside diamonds less visible to the eye or even under magnification. Fractures are very common inside diamonds and are created during the creation in the earths crust. As the rough diamond travels up from the earths crust through volcanic pipes it comes under extreme stresses and pressures and this process, which involves the use of specially-formulated solutions with a refractive index approximating that of diamond, was pioneered by Zvi Yehuda of Ramat Gan, Israel. Yehuda is now used as a name applied to diamonds treated in this manner. Koss & Schechter, another Israel-based firm, attempted to modify Yehudas process in the 1990s by using halogen-based glasses, the details behind the Yehuda process have been kept secret, but the filler used is reported to be lead oxychloride glass, which has a fairly low melting point. The flashes are best seen with the field of nearly parallel to the filled fractures plane. In strongly colored diamonds the flash effect may be missed if examination is less than thorough, for example, in brown-tinted champagne diamonds, the orange-yellow flashes are concealed, leaving only the blue-purple flashes to be seen. For this reason fracture-filling is normally applied to stones whose size is large enough to justify the treatment, however
13.
Millennium Dome raid
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The Millennium Dome raid was an attempted robbery of the Millennium Domes diamond exhibition in Greenwich, South East London occurring on 7 November 2000. A local gang planned to ram-raid the De Beers diamond exhibition which was being held in the dome at the time, the gang had then planned to escape via the Thames in a speedboat. Also on display were priceless blue diamonds, the operation to foil the robbery was the biggest operation undertaken in the Flying Squads history and at trial the judge in the case commended the way it was carried out. If the heist had succeeded, then with a haul of £350 million worth of diamonds, in the summer of 2000, the Flying Squad became aware of a major armed robbery plot after a tip-off was received. The location of this robbery was unclear, but the identities of some of the robbers were known to the police, the police spent a number of months developing intelligence on the plot and set up an operation that they codenamed Operation Magician. During the intelligence gathering the location of the robbery was found to be the Millennium Dome in Greenwich, in February 2000, armed men tried to pull off a £10 million raid on a security van in Nine Elms, South London. The gunmen had stopped the security lorry by blocking off both ends of Nine Elms Lane and they had planned to use their own lorry, which was carrying Christmas trees, as a battering ram. This lorry had a metal spike welded into the chassis. The gang planned to split the security lorrys rear doors with the ram, the gangs plan failed when a motorist who was late for work removed the keys from the ignition of the unattended Christmas tree van. The robbers, left no choice, made their escape in an inflatable speedboat towards Chelsea. It was attempted again on 7 July in Aylesford, Kent and this time, the gang got even closer to the cash, with the metal spike being rammed into the van. They were seconds from taking the money when a police car appeared. Detective Superintendent Jon Shatford stated that this attempted robbery brought to his attention a gang which was capable of carrying out a robbery with this level of planning. Fifteen months after this robbery, there was another case where a gang tried to pull off another robbery using similar techniques. After this unsuccessful robbery the police received a tip-off about the Dome raid from an informer and it was this comment that led to beginning an investigation into the raid. On 1 September 2000 the team identified three of the suspected robbers – Lee Wenham, Raymond Betson and William Cockram – at the Dome and it was then found that every time they had visited the attraction, the Thames was at high tide. They were observed visiting the exhibition and recording footage, leading the police to suspect that the exhibition could be a target. The surveillance on the men was significantly increased and the Dome was placed under close watch, the precautions taken by the Flying Squad included replacing the priceless gems with replicas of the same size, allowing the originals to be stored elsewhere
14.
Amsterdam Airport Schiphol
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Amsterdam Airport Schiphol is the main international airport of the Netherlands, located 9 kilometres southwest of Amsterdam, in the municipality of Haarlemmermeer, province of North Holland. It is the third busiest airport in Europe in terms of passengers, the airport is built as a single-terminal concept, one large terminal split into three large departure halls. Schiphol is the hub for KLM and its regional affiliate KLM Cityhopper as well as for Corendon Dutch Airlines, Martinair, Transavia, the airport also serves as a European hub for Delta Air Lines and Jet Airways and as a base for EasyJet and Vueling. Schiphol opened on 16 September 1916 as a military airbase, the end of the First World War also saw the beginning of civilian use of Schiphol Airport and the airport eventually lost its military role completely. By 1940, Schiphol had four runways at 45-degree angles. The airport was captured by the German military that same year, the airport was destroyed through bombing but at the end of the war the airfield was restored quickly. In 1949, it was decided that Schiphol was to become the airport of the Netherlands. The airports official English name, Amsterdam Airport Schiphol, reflects the original Dutch word order, Schiphol Airport is an important European airport, ranking as Europes third busiest and the worlds fourteenth busiest by total passenger traffic in 2015. It also ranks as the fifth busiest by international passenger traffic. 58.285 million passengers passed through the airport in 2015. In 2010,65. 9% of passengers using the airport flew to and from Europe,11. 7% to and from North America and 8. 8% to and from Asia, in 2010,106 carriers provided a total of 301 destinations on a regular basis. Passenger destinations were offered by 91 airlines, direct destinations grew by 9 to a total of 274. Regular destinations serviced exclusively by full freighters grew by eight to a total of twenty-seven, the airport is built as one large terminal, split into three large departure halls, which connect again once airside. The most recent of these was completed in 1994 and expanded in 2007 with a new section, called Terminal 4, plans for further terminal expansion exist, including the construction of a separate new terminal between the Zwanenburgbaan and Polderbaan runways that would end the one-terminal concept. Because of intense traffic and high landing fees, some low-cost carriers decided to move their flights to airports, such as Rotterdam The Hague Airport. Many low-cost carriers, such as EasyJet, however, continue to operate from Schiphol, there have been talks about using the Lelystad Airport for low-cost carriers. Schiphol is equipped with eighteen double jetway gates in preparation for airlines introducing the Airbus A380, Emirates was the first airline to fly the A380 to Schiphol in August 2012, deploying the aircraft on its double daily Dubai–Amsterdam service. During the summer, China Southern Airlines also uses the A380 on its Beijing–Amsterdam route, Schiphols name is derived from a former fortification named Fort Schiphol, which was part of the Stelling van Amsterdam defence works
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2009 Graff Diamonds robbery
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The Graff Diamonds robbery took place on 6 August 2009 when two men posing as customers entered the premises of Graff Diamonds in New Bond Street, London and stole jewellery worth nearly £40 million. It was believed to be the largest ever gems heist in Britain at the time, the thieves haul totalled 43 items of jewellery, consisting of rings, bracelets, necklaces and wristwatches. One necklace alone has been reported as being more than £3. 5m Britains previous largest jewellery robbery also took place at Graffs. As of September 2014, none of the jewels have been recovered. The robbers used the services of a professional make-up artist to alter their skin tones and their features using latex prosthetics, the artist took four hours to apply the disguises, having been told that it was for a music video. The same make-up studio had unwittingly helped disguise members of the gang robbed the Securitas depot in 2006. On 6 August 2009 at 4.40 pm, two dressed men arrived at the Graff Diamonds jewellery store by taxi and once inside produced two handguns which they used to threaten staff. They made no attempt to conceal their faces from the premises CCTV cameras due to their elaborate disguises, even though one of the robbers was wearing leather gloves, store security allowed him entry, being used to the eccentric behaviour of some super-wealthy clients. Petra Ehnar, an assistant, was forced at gunpoint to empty the stores display cabinets. A total of 43 rings, bracelets, necklaces and watches were taken and she was briefly held hostage at gunpoint and was forced into the street during the getaway. She testified that the robbers told her that she would be killed if she did not carry out their demands. After releasing the hostage outside the store, one of the robbers fired a shot into the air to create confusion, and both escaped the scene in a blue BMW vehicle. This vehicle was abandoned in nearby Dover Street, where a second gunshot was fired into the ground while the robbers switched to a second vehicle and they again switched vehicles in Farm Street, after which there was no further information regarding their whereabouts. All of the diamonds had been laser-inscribed with the Graff logo, detectives investigating the robbery stated, They knew exactly what they were looking for and we suspect they already had a market for the jewels. The suspects details were circulated to all ports and airports but police believed they would have an elaborately prepared escape route and had left the country. The robbery was being investigated by Barnes Flying Squad, headed by Detective Chief Inspector Pam Mace. Since none of the jewellery was recovered as of March 2011, Graff Diamonds, owned by the billionaire Laurence Graff. The actual value of the pieces for insurance purposes, was put at $39 million, but according to Nicholas Paine, the company secretary, the syndicate that insured Graff was only liable for $28.9 million
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Brussels Airport diamond heist
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The heist was accomplished without a shot being fired. The robbers hid in a site outside the airport prior to the robbery. They were armed with Kalashnikov-type assault rifles and dressed as police officers, de Wolf stated that the window for opportunity was so small that the perpetrators must have known ahead of time about the transfer procedures and timing. The robbers stopped the plane and then brandished their guns, stopping the pilots, the Brussels prosecutors office described the weapons used as like Kalashnikovs, most likely the Galil. The robbers never dropped their weapons, the robbers loaded 130 bags into their cars and drove off, but left behind some gems in their hurry. The whole robbery took about 20 minutes, the robbery did not appear to disturb any of the passengers. In fact, the passengers did not know anything had happened until they were told to disembark because the flight had been cancelled. The van believed to be used in the robbery was found abandoned and burned. Belgian prosecutor Ine Van Wymersch said the thieves were very, very professional, antwerp Diamond Heist List of missing treasure Lufthansa heist
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Inclusion (mineral)
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In mineralogy, an inclusion is any material that is trapped inside a mineral during its formation. In gemology, an inclusion is a characteristic enclosed within a gemstone, according to Huttons law of inclusions, fragments included in a host rock are older than the host rock itself. Inclusions are usually other minerals or rocks, but may also be water, liquid or vapor inclusions are known as fluid inclusions. In the case of amber it is possible to find insects and plants as inclusions, the analysis of atmospheric gas bubbles as inclusions in ice cores is an important tool in the study of climate change. A xenolith is a rock which has been picked up by a lava flow. Melt inclusions form when bits of melt become trapped inside crystals as they form in the melt, inclusions are one of the most important factors when it comes to gem valuation. In many gemstones, such as diamonds, inclusions affect the clarity of the gem, in some gems, however, such as star sapphires, the inclusion actually increases the value of the gem. Many colored gemstones, such as amethyst, emerald, and sapphire, are expected to have inclusions, colored gemstones are categorized into three types as follows, Type I colored gems include gems with very little or no inclusions. They include aquamarines, topaz and zircon, Type II colored gems include those that often have a few inclusions. They include sapphire, ruby, garnet and spinel, Type III colored gems include those that almost always have inclusions. Gems in this category include emerald and tourmaline, the term inclusion is also used in the context of metallurgy and metals processing. During the melt stage of processing hard particles such as oxides can enter or form in the metal which are subsequently trapped when the melt solidifies. The term is used negatively such as when the particle could act as a fatigue crack nucleator or as an area of high stress intensity
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Fingerprint
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A fingerprint in its narrow sense is an impression left by the friction ridges of a human finger. The recovery of fingerprints from a scene is an important method of forensic science. Fingerprints are easily deposited on surfaces by the natural secretions of sweat from the eccrine glands that are present in epidermal ridges. These are sometimes referred to as Chanced Impressions, in a wider use of the term, fingerprints are the traces of an impression from the friction ridges of any part of a human or other primate hand. A print from the sole of the foot can also leave an impression of friction ridges, deliberate impressions of fingerprints may be formed by ink or other substances transferred from the peaks of friction ridges on the skin to a relatively smooth surface such as a fingerprint card. Fingerprint records normally contain impressions from the pad on the last joint of fingers and thumbs, human fingerprints are detailed, nearly unique, difficult to alter, and durable over the life of an individual, making them suitable as long-term markers of human identity. Fingerprint analysis, in use since the early 20th century, has led to many crimes being solved and this means that many criminals consider gloves essential. In 2015, the identification of sex by use of a fingerprint test has been reported. A friction ridge is a portion of the epidermis on the digits. These are sometimes known as epidermal ridges which are caused by the interface between the dermal papillae of the dermis and the interpapillary pegs of the epidermis. These ridges may also assist in gripping surfaces and may improve surface contact in wet conditions. Before computerisation, manual filing systems were used in large fingerprint repositories, manual classification systems were based on the general ridge patterns of several or all fingers. This allowed the filing and retrieval of paper records in large collections based on friction ridge patterns alone, the most popular systems used the pattern class of each finger to form a key to assist lookup in a filing system. Classification systems include the Roscher system, the Juan Vucetich system, in the Henry system of classification, there are three basic fingerprint patterns, loop, whorl, and arch, which constitute 60–65%, 30–35%, and 5% of all fingerprints respectively. Ulnar loops start on the pinky-side of the finger, the closer to the ulna. Radial loops start on the thumb-side of the finger, the closer to the radius. Whorls may also have sub-group classifications including plain whorls, accidental whorls, double loop whorls, peacocks eye, composite, other common fingerprint patterns include the tented arch, the plain arch, and the central pocket loop. The system used by most experts, although complex, is similar to the Henry System of Classification
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Diamond flaw
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Few diamonds are perfect, most of them have inclusions or imperfections. These inclusions are known as flaws and exist in various forms. Inclusions are also classified in the manner in which they were formed, for example, syngenetic diamond inclusions are inclusions which were formed while a diamond formed, while epigenetic inclusions occurred after a diamond was formed. The presence or absence of flaws or inclusions in a diamond is usually decided by examining the stone carefully with a lens having the standard magnifications of 10x, no other magnification should be taken as authoritative. Stones which show no apparent flaws or inclusions under this magnification are regarded as flawless, the term for a scarcely perceptible inclusion is VVS for very very slight – which is sometimes offered as flawless. Slightly larger flaws or groups of very thin inclusions are termed VS, larger flaws or inclusions are termed as SI. Even larger flaws are termed as 1st pique, slightly larger flaws classify the stone as 2nd pique and so on. Any flaws which are visible with the eye would be sufficient to scale the price down considerably. These diamond flaws are present on the surface of a stone, however, these are more likely to be caused by the external environment when a diamond was being cut and polished. These are fine lines found on the surface of the diamond and they may have been present naturally or caused when a diamond was cut. While minor scratches can be removed through proper polishing, deep scratches can rarely be removed by treating the diamond and these are usually cut to remove blemishes or certain close to surface inclusions on diamonds. At times these extra facets are cut to enhance the brilliance of the diamond. These do not usually affect the clarity grade of a diamond, a breakage in diamonds that is not parallel to the cleavage plane is referred to as a fracture. Fractures are usually irregular in shape, making a diamond look chipped, the practice of fracture filling is commonly employed to improve the diamond clarity of such diamonds. Fingerprint inclusions in the shape of fingerprints can sometimes be found in diamonds, however, such inclusions are rare in diamonds as compared to other stones, such as rubies. Such inclusions are formed during fluid assisted partial healing of fractures already present in stones. For this to place in diamonds, high temperatures and pressure are required. Few such inclusions have been reported in natural blue and colorless diamonds, while this could indicate that diamonds have been HTHP treated, giving the required temperatures for fingerprint inclusions, such is not always the case
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American Gemological Society
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The American Gem Society is a trade association of retail jewelers, independent appraisers, suppliers, and selective industry members, which was founded in 1934 by Robert M. Shipley. Members are held to a code of ethics with emphasis on consumer protection and education. The Society is based in Las Vegas, Nevada, along with the affiliated American Gem Society Laboratories, the Society trains and certifies jewelers, gemologists, and jewelry appraisers. Diamond grading is the specialty of the American Gem Society Laboratories and the Society has developed its own cut, color, the AGS was created by a man named Robert M. Shipley. During the 1920s, Shipley was operating successfully as a jeweler. However, despite his years in the industry, his lack of expertise regarding gems, humbled by this revelation, Shipley realized that this was a big problem among American jewelers, one which likely accounted for much of the public’s distrust for the profession at the time. Shipley lost his jewelry stores in a divorce and went to Europe and he brought his newfound expertise back to Los Angeles, where he founded his own preliminary course in gemology on September 16,1930. For the next few years he worked to promote the need for gemological education and these jewelers would form the foundation of the Gemological Institute of America, and later the AGS. In its history, the AGS has achieved significant accomplishments within the field of gemology, among these are the following, Invented the industry’s first scientifically reviewed, objective, and repeatable Cut Grade method. Created the Ideal Cut Grade for Round Brilliant shaped diamonds, often known as the AGS Ideal or the Triple Zero Cut, offered the industry’s first diamond grading reports with a Cut Grade for Princess, Emerald, Oval, and other fancy diamond shapes. A big part of the AGS operation comes in the form of AGS Laboratories, primary among these are their diamond grading services. Jewelers are able to have their diamonds scientifically evaluated according to the Four C’s, Color, Clarity, Cut and they are then given a diamond grading report, which can be provided to a consumer in order to verify the quality of the diamond they are purchasing. Additionally, AGS Laboratories offers laser inscription services, through the use of a microlaser beam, the laboratory can inscribe a diamond with a serial number, a company logo, or other text on the stone. This service does not affect the quality of the diamond, and is performed on the girdle where it can only be viewed with a magnification device. American Gem Society website AGS Laboratories website AGS Advanced Instruments Division website
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Magnification
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Magnification is the process of enlarging something only in appearance, not in physical size. This enlargement is quantified by a number also called magnification. When this number is less one, it refers to a reduction in size. Typically, magnification is related to scaling up visuals or images to be able to see detail, increasing resolution, using microscope, printing techniques. In all cases, the magnification of the image does not change the perspective of the image, some optical instruments provide visual aid by magnifying small or distant subjects. A magnifying glass, which uses a lens to make things look bigger by allowing the user to hold them closer to their eye. A microscope, which makes an object appear as a much larger image at a comfortable distance for viewing. A microscope is similar in layout to a telescope except that the object being viewed is close to the objective, a slide projector, which projects a large image of a small slide on a screen. Optical magnification is the ratio between the apparent size of an object and its size, and thus it is a dimensionless number. Optical magnification is sometimes referred to as power, although this can lead to confusion with optical power, for real images, such as images projected on a screen, size means a linear dimension. For optical instruments with an eyepiece, the dimension of the image seen in the eyepiece cannot be given. Strictly speaking, one should take the tangent of that angle, example, The angular size of the full moon is 0. 5°. In binoculars with 10x magnification it appears to subtend an angle of 5°, the linear magnification of a thin lens is where f is the focal length and d o is the distance from the lens to the object. Note that for real images, M is negative and the image is inverted, for virtual images, M is positive and the image is upright. The image recorded by a film or image sensor is always a real image and is usually inverted. When measuring the height of an image using the cartesian sign convention the value for hi will be negative. However, the sign convention used in photography is real is positive. Therefore in photography, Object height and distance are always real, when the focal length is positive the images height, distance and magnification are real and positive
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Achromatic lens
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An achromatic lens or achromat is a lens that is designed to limit the effects of chromatic and spherical aberration. Achromatic lenses are corrected to bring two wavelengths into focus in the same plane, the most common type of achromat is the achromatic doublet, which is composed of two individual lenses made from glasses with different amounts of dispersion. The lens elements are mounted next to other, often cemented together. In the most common type, the power of the crown lens element is not quite equalled by the negative power of the flint lens element. Together they form a positive lens that will bring two different wavelengths of light to a common focus. Negative doublets, in which the negative-power element predominates, are also made, theoretical considerations of the feasibility of correcting chromatic aberration were debated in the 18th century following Newtons statement that such a correction was impossible. Credit for the invention of the first achromatic doublet is often given to an English barrister, Hall wished to keep his work on the achromatic lenses a secret and contracted the manufacture of the crown and flint lenses to two different opticians, Edward Scarlett and James Mann. They in turn sub-contracted the work to the person, George Bass. He realized the two components were for the client and, after fitting the two parts together, noted the achromatic properties. Hall failed to appreciate the importance of his invention, and it remained known to only a few opticians, in the late 1750s, Bass mentioned Halls lenses to John Dollond, who understood their potential and was able to reproduce their design. Dollond applied for and was granted a patent on the technology in 1758, dollonds son Peter invented the apochromat, an improvement on the achromat, in 1763. Several different types of achromat have been devised and they differ in the shape of the included lens elements as well as in the optical properties of their glass. In the following, R denotes the radius of the spheres that define the optically relevant refracting lens surfaces, by convention, R1 denotes the first lens surface counted from the object. A doublet lens has four surfaces with radii R1 to R4, uses an equiconvex crown glass lens with R1=R2, and a second flint glass lens with R3=-R2. The back of the flint glass lens is flat, a Littrow doublet can produce a ghost image between R2 and R3 because the lens surfaces of the two lenses have the same radii. When used in a telescope, it may produce a ghost image between the flat R4 surface and rear of the tube. The first lens has positive refractive power, the second negative, R1 is set greater than R2, and R2 is set close to, but not equal to, R3. R4 is usually greater than R3, in a Fraunhofer doublet, the dissimilar curvatures of R2 and R3 are mounted close, but not in contact
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Spherical aberration
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It signifies a deviation of the device from the norm, i. e. it results in an imperfection of the produced image. A spherical lens has a point only at a radius that equals the radius of the sphere divided by the index of refraction of the lens material. A typical value of refractive index for crown glass is 1.5 and it is often considered to be an imperfection of telescopes and other instruments which makes their focusing less than ideal due to the spherical shape of lenses and mirrors. This is an important effect, because spherical shapes are easier to produce than aspherical ones. In many cases, it is cheaper to use multiple elements to compensate for spherical aberration than it is to use a single aspheric lens. Positive spherical aberration means peripheral rays are bent too much, negative spherical aberration means peripheral rays are not bent enough. The effect is proportional to the power of the diameter and inversely proportional to the third power of the focal length, so it is much more pronounced at short focal ratios. In lens systems, the effect can be minimized using special combinations of convex and concave lenses, for simple designs one can sometimes calculate parameters that minimize spherical aberration. For small telescopes using spherical mirrors with focal ratios shorter than f/10, particularly, light striking the inner part of the mirror focuses farther from the mirror than light striking the outer part. As a result the image cannot be focused as sharply as if the aberration were not present, because of spherical aberration, telescopes shorter than f/10 are usually made with non-spherical mirrors or with correcting lenses. com, PA van Walree, viewed 28 January 2007
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Market liquidity
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In business, economics or investment, market liquidity is a markets ability to purchase or sell an asset without causing drastic change in the assets price. Equivalently, a market liquidity describes the assets ability to sell quickly without having to reduce its price to a significant degree. Liquidity is about how big the trade-off is between the speed of the sale and the price it can be sold for, in a liquid market, the trade-off is mild, selling quickly will not reduce the price much. In a relatively illiquid market, selling it quickly will require cutting its price by some amount, money, or cash, is the most liquid asset, because it can be sold for goods and services instantly with no loss of value. There is no wait for a buyer of the cash. There is no trade-off between speed and value and it can be used immediately to perform economic actions like buying, selling, or paying debt, meeting immediate wants and needs. If an asset is moderately liquid, it has moderate liquidity, in an alternative definition, liquidity can mean the amount of cash and cash equivalents. If a business has moderate liquidity, it has an amount of very liquid assets. If a business has sufficient liquidity, it has a sufficient amount of liquid assets. An act of exchanging a less liquid asset for a liquid asset is called liquidation. Often liquidation is trading the less liquid asset for cash, also known as selling it, for the same asset, its liquidity can change through time or between different markets, such as in different countries. The change in the liquidity is just based on the market liquidity for the asset at the particular time or in the particular country. The liquidity of a product can be measured as how often it is bought, Liquidity is defined formally in many accounting regimes and has in recent years been more strictly defined. For instance, the US Federal Reserve intends to apply quantitative liquidity requirements based on Basel III liquidity rules as of fiscal 2012, bank directors will also be required to know of, and approve, major liquidity risks personally. A liquid asset has some or all of the features, It can be sold rapidly, with minimal loss of value. The essential characteristic of a market is that there are always ready. A market may be considered both deep and liquid if there are ready and willing buyers and sellers in large quantities, an illiquid asset is an asset which is not readily salable due to uncertainty about its value or the lack of a market in which it is regularly traded. The mortgage-related assets which resulted in the mortgage crisis are examples of illiquid assets
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Consumer
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A consumer is a person or organization that uses economic services or commodities. In economic systems consumers are utilities expressed in the decision to trade or not, the consumer is the one who pays to consume goods and services produced. As such, consumers play a role in the economic system of a nation. Without consumer demand, producers would lack one of the key motivations to produce, the consumer also forms part of the chain of distribution. The law primarily uses the notion of the consumer in relation to protection laws. As of all voters are also consumers, consumer protection takes on a clear political significance. Concern over the interests of consumers has also spawned activism, as well as incorporation of consumer education into school curricula, there are also various non-profit publications, such as Which. Consumer Reports and Choice Magazine, dedicated to assist in education and decision making. In India, the Consumer Protection Act 1986 differentiates the consummation of a commodity or service for use or to earn a livelihood. Only consumers are protected per this act and any person, entity or organization purchasing a commodity for commercial reasons are exempted from any benefits of this act, U. S. Government National Consumer Protection Week
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Blow torch
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A blowtorch, or blowlamp, is a fuel-burning tool used for applying flame and heat to various applications, usually metalworking. Early blowtorches used liquid fuel, carried in a reservoir attached to the lamp. Their fuel reservoir is disposable or refillable by exchange, the term blowlamp usually refers to liquid-fuelled torches still used in the UK. Liquid-fuelled torches are pressurized by a hand pump, while gas torches are self-pressurized by the fuel evaporation. Fuel torches are available in a vast range of size and output power, the term blowtorch applies to the smaller and lower temperature range of these. Blowtorches are typically a single unit, with their draught supplied by a natural draught of air. The larger torches may have a fuel reservoir placed on the ground. This is common for butane- or propane-fuelled gas torches, but also applies to the older, many torches now use a hose-supplied gas feed, which is often mains gas. They may also have a supply, from either an air blower or an oxygen cylinder. Both of these larger and more powerful designs are commonly described as blowtorches, while the term blowtorch is usually reserved for the smaller. The archaic term blowpipe is sometimes used in relation to oxy-acetylene welding torches. The blowtorch is of ancient origin and was used as a tool by gold and they began literally as a blown lamp, a wick oil lamp with a mouth-blown tube alongside the flame. This type of lamp, with fuel, continued to be in use for such small tasks into the late 20th century. In 1797 or in 1799 German inventor August von Marquardt invented a blowtorch in Eberswalde, another early blow pipe patent comes from USA, dated May 13,1856. In 1882, a new vaporizing technique was developed by Carl Richard Nyberg in Sweden, and the year after and it was quickly copied or licensed by many other manufacturers. The US blowtorch was independently developed with a flared base and was fuelled by gasoline, whereas the European versions used kerosene for safety. There remain several manufacturers producing brass blowtorches in India, China, the blowtorch is commonly used where a diffuse high temperature naked flame heat is required but not so hot as to cause combustion or welding. Temperature applications, soldering, brazing, softening paint for removal, melting roof tar and it is also used in cooking, one common use is for the creation of the layer of hard caramelized sugar in a crème brûlée
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International Standard Book Number
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The International Standard Book Number is a unique numeric commercial book identifier. An ISBN is assigned to each edition and variation of a book, for example, an e-book, a paperback and a hardcover edition of the same book would each have a different ISBN. The ISBN is 13 digits long if assigned on or after 1 January 2007, the method of assigning an ISBN is nation-based and varies from country to country, often depending on how large the publishing industry is within a country. The initial ISBN configuration of recognition was generated in 1967 based upon the 9-digit Standard Book Numbering created in 1966, the 10-digit ISBN format was developed by the International Organization for Standardization and was published in 1970 as international standard ISO2108. Occasionally, a book may appear without a printed ISBN if it is printed privately or the author does not follow the usual ISBN procedure, however, this can be rectified later. Another identifier, the International Standard Serial Number, identifies periodical publications such as magazines, the ISBN configuration of recognition was generated in 1967 in the United Kingdom by David Whitaker and in 1968 in the US by Emery Koltay. The 10-digit ISBN format was developed by the International Organization for Standardization and was published in 1970 as international standard ISO2108, the United Kingdom continued to use the 9-digit SBN code until 1974. The ISO on-line facility only refers back to 1978, an SBN may be converted to an ISBN by prefixing the digit 0. For example, the edition of Mr. J. G. Reeder Returns, published by Hodder in 1965, has SBN340013818 -340 indicating the publisher,01381 their serial number. This can be converted to ISBN 0-340-01381-8, the check digit does not need to be re-calculated, since 1 January 2007, ISBNs have contained 13 digits, a format that is compatible with Bookland European Article Number EAN-13s. An ISBN is assigned to each edition and variation of a book, for example, an ebook, a paperback, and a hardcover edition of the same book would each have a different ISBN. The ISBN is 13 digits long if assigned on or after 1 January 2007, a 13-digit ISBN can be separated into its parts, and when this is done it is customary to separate the parts with hyphens or spaces. Separating the parts of a 10-digit ISBN is also done with either hyphens or spaces, figuring out how to correctly separate a given ISBN number is complicated, because most of the parts do not use a fixed number of digits. ISBN issuance is country-specific, in that ISBNs are issued by the ISBN registration agency that is responsible for country or territory regardless of the publication language. Some ISBN registration agencies are based in national libraries or within ministries of culture, in other cases, the ISBN registration service is provided by organisations such as bibliographic data providers that are not government funded. In Canada, ISBNs are issued at no cost with the purpose of encouraging Canadian culture. In the United Kingdom, United States, and some countries, where the service is provided by non-government-funded organisations. Australia, ISBNs are issued by the library services agency Thorpe-Bowker
