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Turquoise
Turquoise is an opaque, blue-to-green mineral that is a hydrated phosphate of copper and aluminium, with the chemical formula . It is rare and valuable in finer grades and has been prized as a gemstone and ornamental stone for thousands of years owing to its unique hue. Like most other opaque gems, turquoise has been devalued by the introduction of treatments, imitations and synthetics into the market. The robin's egg blue or sky blue color of the Persian turquoise mined near the modern city of Nishapur in Iran has been used as a guiding reference for evaluating turquoise quality. Names The word ''turquoise'' dates to the 17th century and is derived from the French ''turquois'' meaning "Turkish" because the mineral was first brought to Europe through the Ottoman Empire.Turquoise . minerals.usgs.gov Howe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Turquoise (color)
Turquoise ( ) is a blue-green color, based on the mineral of the same name. The word ''turquoise'' dates to the 17th century and is derived from the French , meaning 'Turkish', because the mineral was first brought to Europe through Turkey from mines in the historical Khorasan province of Iran (Persia) and Afghanistan. The first recorded use of ''turquoise'' as a color name in English was in 1573. The X11 color named turquoise is displayed on the right. Turquoise gemstones Turquoise is an opaque, blue-to-green mineral that is a hydrous phosphate of copper and aluminium, with the chemical formula Cu Al6( P O4)4(O H)8·4 H2O. It is rare and valuable in finer grades and has been prized as a gem and ornamental stone for thousands of years owing to its unique hue. In many cultures of the Old and New Worlds, this gemstone has been esteemed for thousands of years as a holy stone, a bringer of good fortune or a talisman. The oldest evidence for this claim was found in ancien ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nishapur
Nishapur or officially Romanized as Neyshabur ( fa, ;Or also "نیشاپور" which is closer to its original and historic meaning though it is less commonly used by modern native Persian speakers. In Persian poetry, the name of this city is written and pronounced as "نِشابور" (without the usage of "پ" or "ب"). In modern times and among the general public and the Persian mass media, "نیشابور" is the most commonly used style of pronunciation and spelling of this city though "نیشاپور" is also correct. Nišâpur, Nişapur, Nīshābūr, or Neyshapur are also the other Romanizations of this city. from Middle Persian ''"New-Shapuhr"'', meaning: "The New City of Shapur", "The Fair Shapur", or "The Perfect built of Shapur") is the second-largest city of Razavi Khorasan Province in the Northeast of Iran. Nishapur is situated in a fertile plain at the foot of Binalud Mountain Range and has been the historic capital of the Western Quarter of Greater Khorasan, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphate Minerals
Phosphate minerals contain the tetrahedrally coordinated phosphate (PO43−) anion along sometimes with arsenate (AsO43−) and vanadate (VO43−) substitutions, and chloride (Cl−), fluoride (F−), and hydroxide (OH−) anions that also fit into the crystal structure. The phosphate class of minerals is a large and diverse group, however, only a few species are relatively common. Applications Phosphate rock has high concentration of phosphate minerals, most commonly of the apatite group. It is the major resource mined to produce phosphate fertilizers for the agriculture sector. Phosphate is also used in animal feed supplements, food preservatives, anti-corrosion agents, cosmetics, fungicides, ceramics, water treatment and metallurgy. The largest use of minerals mined for their phosphate content is the production of fertilizer. Phosphate minerals are often used for control of rust and prevention of corrosion on ferrous materials applied with electrochemical conversion co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iran
Iran, officially the Islamic Republic of Iran, and also called Persia, is a country located in Western Asia. It is bordered by Iraq and Turkey to the west, by Azerbaijan and Armenia to the northwest, by the Caspian Sea and Turkmenistan to the north, by Afghanistan and Pakistan to the east, and by the Gulf of Oman and the Persian Gulf to the south. It covers an area of , making it the 17th-largest country. Iran has a population of 86 million, making it the 17th-most populous country in the world, and the second-largest in the Middle East. Its largest cities, in descending order, are the capital Tehran, Mashhad, Isfahan, Karaj, Shiraz, and Tabriz. The country is home to one of the world's oldest civilizations, beginning with the formation of the Elamite kingdoms in the fourth millennium BC. It was first unified by the Medes, an ancient Iranian people, in the seventh century BC, and reached its territorial height in the sixth century BC, when Cyrus the Great fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gemstone
A gemstone (also called a fine gem, jewel, precious stone, or semiprecious stone) is a piece of mineral crystal which, in cut and polished form, is used to make jewelry or other adornments. However, certain rocks (such as lapis lazuli, opal, and obsidian) and occasionally organic materials that are not minerals (such as amber, jet, and pearl) are also used for jewelry and are therefore often considered to be gemstones as well. Most gemstones are hard, but some soft minerals are used in jewelry because of their luster or other physical properties that have aesthetic value. Rarity and notoriety are other characteristics that lend value to gemstones. Apart from jewelry, from earliest antiquity engraved gems and hardstone carvings, such as cups, were major luxury art forms. A gem expert is a gemologist, a gem maker is called a lapidarist or gemcutter; a diamond cutter is called a diamantaire. Characteristics and classification The traditional classification in the West, wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crystal
A crystal or crystalline solid is a solid material whose constituents (such as atoms, molecules, or ions) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions. In addition, macroscopic single crystals are usually identifiable by their geometrical shape, consisting of flat faces with specific, characteristic orientations. The scientific study of crystals and crystal formation is known as crystallography. The process of crystal formation via mechanisms of crystal growth is called crystallization or solidification. The word ''crystal'' derives from the Ancient Greek word (), meaning both "ice" and "rock crystal", from (), "icy cold, frost". Examples of large crystals include snowflakes, diamonds, and table salt. Most inorganic solids are not crystals but polycrystals, i.e. many microscopic crystals fused together into a single solid. Polycrystals include most metals, rocks, ceramics, and ice. A third category of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cryptocrystalline
Cryptocrystalline is a rock microstructure, rock texture made up of such minute crystals that its crystalline nature is only vaguely revealed even microscopically in thin section by transmitted polarized light. Among the sedimentary rocks, chert and flint are cryptocrystalline. carbonado (diamond), Carbonado, a form of diamond, is also cryptocrystalline. Volcanic rocks, especially of the felsic type such as felsites and rhyolites, may have a cryptocrystalline matrix (geology), groundmass as distinguished from pure obsidian (felsic) or tachylyte (mafic), which are natural rock glasses. Agate and onyx are examples of cryptocrystalline silica (chalcedony). See also * List of rock textures * Macrocrystalline * Microcrystalline * Nanocrystalline * Rock microstructure References Crystals Lithics Petrology concepts {{Petrology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glass
Glass is a non-crystalline, often transparent, amorphous solid that has widespread practical, technological, and decorative use in, for example, window panes, tableware, and optics. Glass is most often formed by rapid cooling (quenching) of the molten form; some glasses such as volcanic glass are naturally occurring. The most familiar, and historically the oldest, types of manufactured glass are "silicate glasses" based on the chemical compound silica (silicon dioxide, or quartz), the primary constituent of sand. Soda–lime glass, containing around 70% silica, accounts for around 90% of manufactured glass. The term ''glass'', in popular usage, is often used to refer only to this type of material, although silica-free glasses often have desirable properties for applications in modern communications technology. Some objects, such as drinking glasses and eyeglasses, are so commonly made of silicate-based glass that they are simply called by the name of the material. Despite bei ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mohs Scale Of Mineral Hardness
The Mohs scale of mineral hardness () is a qualitative ordinal scale, from 1 to 10, characterizing scratch resistance of various minerals through the ability of harder material to scratch softer material. The scale was introduced in 1812 by the German geologist and mineralogist Friedrich Mohs, in his book ''"Versuch einer Elementar-Methode zur naturhistorischen Bestimmung und Erkennung der Fossilien"''; it is one of several definitions of hardness in materials science, some of which are more quantitative. The method of comparing hardness by observing which minerals can scratch others is of great antiquity, having been mentioned by Theophrastus in his treatise ''On Stones'', , followed by Pliny the Elder in his ''Naturalis Historia'', . The Mohs scale is useful for identification of minerals in the field, but is not an accurate predictor of how well materials endure in an industrial setting – ''toughness''. Minerals The Mohs scale of mineral hardness is based on the ability ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aztec
The Aztecs () were a Mesoamerican culture that flourished in central Mexico in the post-classic period from 1300 to 1521. The Aztec people included different Indigenous peoples of Mexico, ethnic groups of central Mexico, particularly those groups who spoke the Nahuatl, Nahuatl language and who dominated large parts of Mesoamerica from the 14th to the 16th centuries. Aztec culture was organized into city-states (''altepetl''), some of which joined to form alliances, political confederations, or empires. The Aztec Empire was a confederation of three city-states established in 1427: Tenochtitlan, city-state of the Mexica or Tenochca; Texcoco (altepetl), Texcoco; and Tlacopan, previously part of the Tepanec empire, whose dominant power was Azcapotzalco (altepetl), Azcapotzalco. Although the term Aztecs is often narrowly restricted to the Mexica of Tenochtitlan, it is also broadly used to refer to Nahuas, Nahua polities or peoples of central Pre-Columbian Mexico, Mexico in the preh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pliny The Elder
Gaius Plinius Secundus (AD 23/2479), called Pliny the Elder (), was a Roman author, naturalist and natural philosopher, and naval and army commander of the early Roman Empire, and a friend of the emperor Vespasian. He wrote the encyclopedic ''Naturalis Historia'' (''Natural History''), which became an editorial model for encyclopedias. He spent most of his spare time studying, writing, and investigating natural and geographic phenomena in the field. His nephew, Pliny the Younger, wrote of him in a letter to the historian Tacitus: Among Pliny's greatest works was the twenty-volume work ''Bella Germaniae'' ("The History of the German Wars"), which is no longer extant. ''Bella Germaniae'', which began where Aufidius Bassus' ''Libri Belli Germanici'' ("The War with the Germans") left off, was used as a source by other prominent Roman historians, including Plutarch, Tacitus and Suetonius. Tacitus—who many scholars agree had never travelled in Germania—used ''Bella Germani ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Turkic Dynasties And Countries
The following is a list of dynasties, states or empires which are Turkic-speaking, of Turkic origins, or both. There are currently six recognised Turkic sovereign states. Additionally, there are six federal subjects of Russia in which a Turkic language is a majority, and five where Turkic languages are the minority, and also Crimea, a disputed territory between Ukraine and Russia where Turkic languages are the indigenous minority. There have been numerous Turkic confederations, dynasties, and empires throughout history across Eurasia. Contemporary entities with at least one Turkic language recognised as official Current independent states De facto states Recognised only by Turkey. Federal subjects (Republics) of Russia Autonomous regions Historical Turkic confederations, dynasties, and states Tribal confederations Royal clans * Ashina ( First Turkic Khaganate, Western Turkic Khaganate, Eastern Turkic Khaganate, Khazars, Nushibi, Second Turkic Khag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
