Prasiolite
Prasiolite (also known as green quartz, green amethyst or vermarine) is a green variety of quartz. Since 1950, almost all natural prasiolite has come from a small Brazilian mine, but it has also been mined in the Lower Silesia region of Poland. Naturally occurring prasiolite has also been found in the Thunder Bay area of Canada. Most prasiolite sold is used in jewellery settings, where it can substitute for far more expensive precious gemstones. Prasiolite is a rare stone in nature; artificial prasiolite is produced from amethyst. Most amethyst will turn yellow or orange when heated, producing heat-treated amethysts which are often marketed as citrine, but some amethyst will turn green when treated. Currently, almost all prasiolite on the market is made from amethyst via a process of heating and irradiation. Green quartz is sometimes incorrectly called green amethyst, which is not an acceptable name for the material according to Federal Trade Commission Guidelines. Othe ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Quartz
Quartz is a hard, crystalline mineral composed of silica (silicon dioxide). The Atom, atoms are linked in a continuous framework of SiO4 silicon–oxygen Tetrahedral molecular geometry, tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall chemical formula of Silicon dioxide, SiO2. Quartz is, therefore, classified structurally as a Silicate mineral#Tectosilicates, framework silicate mineral and compositionally as an oxide mineral. Quartz is the second most abundant mineral in Earth's continental crust, behind feldspar. Quartz exists in two forms, the normal α-quartz and the high-temperature β-quartz, both of which are chiral. The transformation from α-quartz to β-quartz takes place abruptly at . Since the transformation is accompanied by a significant change in volume, it can easily induce microfracturing of ceramics or rocks passing through this temperature threshold. There are many different varieties of quartz, several of which are classifi ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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List Of Minerals (synonyms)
The International Mineralogical Association (IMA) is the international group that recognises new minerals and new mineral names. However, minerals discovered before 1959 did not go through the official naming procedure although some minerals published previously have been either confirmed or discredited since that date. * Abbreviations: **"*" – discredited (IMA/CNMNC status). **"?" – questionable/doubtful (IMA/CNMNC, mindat.org or mineralienatlas.de status). **N – published without approval of the IMA/CNMNC. **I – intermediate member of a solid-solution series. **H – hypothetical mineral (synthetic, anthropogenic, etc.) ***ch – incomplete description, hypothetical solid solution end member. **group – a name used to designate a group of species, sometimes only a mineral group name. **no – no link available. **red. – redefinition of ... **Y: 1NNN – year of publication. **Y: old – known before publications were available. __TOC__ List of main synonyms Mainly ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Amethyst
Amethyst is a Violet (color), violet variety of quartz. The name comes from the Koine Greek from - , "not" and (Ancient Greek) / (Modern Greek), "intoxicate", a reference to the belief that the stone protected its owner from Alcohol intoxication, drunkenness. Ancient Greece, Ancient Greeks wore amethyst and carved drinking vessels from it in the belief that it would prevent intoxication. Amethyst, a Gemstone, semiprecious stone, is often used in jewelry. Structure Amethyst is a violet variety of quartz () and owes its violet color to Gemstone irradiation, irradiation, impurities of iron () and in some cases other transition metals, and the presence of other trace elements, which result in complex crystal lattice substitutions. The irradiation causes the iron ions that replace silicon, Si in the lattice to lose an electron and form a color center. Amethyst is a three-dimensional network of tetrahedra where the silicon atoms are in the center and are surrounded by fo ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Mineral
In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid substance with a fairly well-defined chemical composition and a specific crystal structure that occurs naturally in pure form.John P. Rafferty, ed. (2011): Minerals'; p. 1. In the series ''Geology: Landforms, Minerals, and Rocks''. Rosen Publishing Group. The Geology, geological definition of mineral normally excludes compounds that occur only in living organisms. However, some minerals are often biogenic (such as calcite) or organic compounds in the sense of chemistry (such as mellite). Moreover, living organisms often synthesize inorganic minerals (such as hydroxylapatite) that also occur in rocks. The concept of mineral is distinct from rock (geology), rock, which is any bulk solid geologic material that is relatively homogeneous at a large enough scale. A rock may consist of one type of mineral or may be an aggregate (geology), aggregate of two or more different types of minerals, spaci ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Leek
A leek is a vegetable, a cultivar of ''Allium ampeloprasum'', the broadleaf wild leek (synonym (taxonomy), syn. ''Allium porrum''). The edible part of the plant is a bundle of Leaf sheath, leaf sheaths that is sometimes erroneously called a "stem" or "stalk". The genus ''Allium'' also contains the onion, garlic, shallot, scallion, chives, and Allium chinense, Chinese onion. Three closely related vegetables—elephant garlic, kurrat and Persian leek or ''tareh''—are also cultivars of ''A. ampeloprasum'', although different in their culinary uses. Etymology Historically, many scientific names were used for leeks, but they are now all treated as cultivars of ''A. ampeloprasum''. The name ''leek'' developed from the Old English word , from which the modern English name for garlic also derives. means 'onion' in Old English and has cognates in other Germanic languages: Danish ' 'onion', Icelandic ' 'onion', Norwegian ' 'onion', Swedish ' 'onion', German ' 'leek', Dutch ' '' ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Greek Language
Greek (, ; , ) is an Indo-European languages, Indo-European language, constituting an independent Hellenic languages, Hellenic branch within the Indo-European language family. It is native to Greece, Cyprus, Italy (in Calabria and Salento), southern Albania, and other regions of the Balkans, Caucasus, the Black Sea coast, Asia Minor, and the Eastern Mediterranean. It has the list of languages by first written accounts, longest documented history of any Indo-European language, spanning at least 3,400 years of written records. Its writing system is the Greek alphabet, which has been used for approximately 2,800 years; previously, Greek was recorded in writing systems such as Linear B and the Cypriot syllabary. The Greek language holds a very important place in the history of the Western world. Beginning with the epics of Homer, ancient Greek literature includes many works of lasting importance in the European canon. Greek is also the language in which many of the foundational texts ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Scallion
Scallions (also known as green onions and spring onions) are edible vegetables of various species in the genus ''Allium''. Scallions generally have a milder taste than most onions. Their close relatives include garlic, shallots, leeks, chives, and Allium chinense, Chinese onions. The leaves are eaten both raw and cooked. Scallions produce hollow, tubular, green leaves that grow directly from the bulb, which does not fully develop. This is different to other ''Allium'' species where bulbs fully develop, such as commercially available onions and garlic. With scallions, the leaves are what is typically chopped into various dishes and used as garnishes. Etymology and naming The names ''scallion'' and ''shallot'' derive from the Old French ''eschalotte'', by way of ''eschaloigne'', from the Latin ''Ascalōnia caepa'' or "Ascalonian onion", a namesake of the ancient Eastern Mediterranean coastal city of Ascalon. Other names used in various parts of the world include spring onion ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Federal Trade Commission
The Federal Trade Commission (FTC) is an independent agency of the United States government whose principal mission is the enforcement of civil (non-criminal) United States antitrust law, antitrust law and the promotion of consumer protection. It shares jurisdiction over federal civil antitrust law enforcement with the United States Department of Justice Antitrust Division, Department of Justice Antitrust Division. The agency is headquartered in the Federal Trade Commission Building in Washington, DC. The FTC was established in 1914 by the Federal Trade Commission Act of 1914, Federal Trade Commission Act, which was passed in response to the 19th-century monopolistic trust crisis. Since its inception, the FTC has enforced the provisions of the Clayton Antitrust Act of 1914, Clayton Act, a key U.S. antitrust statute, as well as the provisions of the FTC Act, et seq. Over time, the FTC has been delegated with the enforcement of additional business regulation statutes and has promul ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Irradiation
Irradiation is the process by which an object is exposed to radiation. An irradiator is a device used to expose an object to radiation, most often gamma radiation, for a variety of purposes. Irradiators may be used for sterilizing medical and pharmaceutical supplies, preserving foodstuffs, alteration of gemstone colors, studying radiation effects, eradicating insects through sterile male release programs, or calibrating thermoluminescent dosimeters (TLDs). The exposure can originate from various sources, including natural sources. Most frequently the term refers to ionizing radiation, and to a level of radiation that will serve a specific purpose, rather than radiation exposure to normal levels of background radiation. The term irradiation usually excludes the exposure to non-ionizing radiation, such as infrared, visible light, microwaves from cellular phones or electromagnetic waves emitted by radio and television receivers and power supplies. Applications Sterilization If ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Citrine Quartz
Citrine is a transparent, yellow variety of quartz. Its name is derived from the Latin word ''citrus'' (citron tree), by way of the French ''citrin'' or ''citron'' (lemon). Citrine is one of the most popular yellow gemstones. It is sometimes used as a modern, more affordable alternative to the traditional November birthstone, topaz. Not every yellow quartz is considered citrine, and there is disagreement as to when the name "citrine" is appropriately used. However, quartz stained by iron inclusions or coatings is generally not considered citrine. Natural citrine is rare; most commercially available citrine is produced by heating amethyst or smoky quartz. Natural citrine tends to have a pale yellow, often smoky color, while heat-treated amethyst is typically a deeper yellow, orange, red, or even brown ("burnt amethyst"). Color File:Citrine 1 (Russie).jpg, Twinned natural citrine crystals from Russia File:Quartz-60953.jpg, Natural citrine crystal from Brazil File:Citrin cut.jpg, ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Tectosilicates
Silicate minerals are rock-forming minerals made up of silicate groups. They are the largest and most important class of minerals and make up approximately 90 percent of Earth's crust. In mineralogy, the crystalline forms of silica (silicon dioxide, ) are usually considered to be Silicate mineral#Tectosilicates, tectosilicates, and they are classified as such in the Dana system (75.1). However, the Nickel-Strunz system classifies them as oxide minerals (4.DA). Silica is found in nature as the mineral quartz, and its polymorphism (materials science), polymorphs. On Earth, a wide variety of silicate minerals occur in an even wider range of combinations as a result of the processes that have been forming and re-working the crust for billions of years. These processes include partial melting, crystallization, fractionation, metamorphism, weathering, and diagenesis. Living organisms also contribute to this carbonate–silicate cycle, geologic cycle. For example, a type of plankton ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Gemstones
A gemstone (also called a fine gem, jewel, precious stone, semiprecious stone, or simply gem) is a piece of mineral crystal which, when cut or polished, is used to make jewelry or other adornments. Certain rocks (such as lapis lazuli, opal, and obsidian) and occasionally organic materials that are not minerals (such as amber, jet, and pearl) may also be used for jewelry and are therefore often considered to be gemstones as well. Most gemstones are hard, but some softer minerals such as brazilianite may be used in jewelry because of their color or luster or other physical properties that have aesthetic value. However, generally speaking, soft minerals are not typically used as gemstones by virtue of their brittleness and lack of durability. Found all over the world, the industry of coloured gemstones (i.e. anything other than diamonds) is currently estimated at US$1.55billion and is projected to steadily increase to a value of $4.46billion by 2033. A gem expert is a gemo ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |