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Arsenuranospathite
Arsenuranospathite ( IMA symbol: Aush) is a rare mineral with the chemical formula Al(UO2)2(AsO4)2F·20H2O. The name "arsenuranospathite" as arsenate analog of uranospathite was first used by Walenta (1963) with reference to a uranyl-arsenate mineral from Black Forest (Schwarzwald) massif, Germany. Later it was undoubtedly demonstrated that the name arsenuranospathite was applied, at least, to two different species – proper arsenuranospathite, ideally Al(UO2)2(AsO4)2F·20H2O, orthorhombic, and its partially dehydrated analogue, Al(UO2)2(AsO4)2F·nH2O (n = 8–10), tetragonal or pseudo-tetragonal. Properties Yellow to yellow-greenish, transparent to opaque tabular and prismatic crystals, with perfect cleavage. Transparent to translucent. Hardness = ~2. Radioactive.http://www.handbookofmineralogy.org/pdfs/arsenuranospathite {{Bare URL PDF, date=March 2022 Chemical composition Contents of Al and U are very stable (1±0.05 and 2±0.07 atoms per As+P+U = 4 apfu respectively). M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Mineral Symbols
Mineral symbols (text abbreviations) are used to abbreviate mineral groups, subgroups, and species, just as lettered symbols are used for the chemical elements. The first set of commonly used mineral symbols was published in 1983 and covered the common rock-forming minerals using 192 two- or three-lettered symbols. These type of symbols are referred to as Kretz symbols. More extensive lists were subsequently made available in the form of publications or posted on journal webpages. A comprehensive list of more than 5,700 IMA-CNMNC approved symbols (referred to as IMA symbols) compiled by L.N. Warr was published in volume 85 (issue 3) of th''Mineralogical Magazine''(2021). These symbols are listed alphabetically in the tables below. The approved listings are compatible with the system used to symbolize the elements, 30 of which occur as minerals. Mineral symbols are most commonly represented by three-lettered text symbols, although one-, two- and four-lettered symbols also exist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arsenate Minerals
Arsenate minerals usually refer to the naturally occurring orthoarsenates, possessing the (AsO4)3− anion group and, more rarely, other arsenates with anions like AsO3(OH)2− (also written HAsO42−) (example: pharmacolite Ca(AsO3OH).2H2O) or (very rarely) sO2(OH)2sup>− (example: andyrobertsite). Arsenite minerals are much less common. Both the Dana and the Strunz mineral classifications place the arsenates in with the phosphate minerals. Example arsenate minerals include: * Annabergite Ni3(AsO4)2·8H2O *Austinite CaZn(AsO4)(OH) *Clinoclase Cu3(AsO4)(OH)3 *Conichalcite CaCu(AsO4)(OH) * Cornubite Cu5(AsO4)2(OH)4 *Cornwallite Cu2+5(AsO4)2(OH)2 *Erythrite Co3(AsO4)2·8H2O *Mimetite Pb5(AsO4)3Cl * Olivenite Cu2(AsO4)OH Nickel–Strunz Classification -08- Phosphates IMA-CNMNC proposes a new hierarchical scheme (Mills et al., 2009). This list uses it to modify the Classification of Nickel–Strunz ( mindat.org, 10 ed, pending publication). *Abbreviations: **"*" - discredi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Mineralogical Association
Founded in 1958, the International Mineralogical Association (IMA) is an international group of 40 national societies. The goal is to promote the science of mineralogy and to standardize the nomenclature of the 5000 plus known mineral species. The IMA is affiliated with the International Union of Geological Sciences (IUGS). The Association supports the activities of Commissions and Working Groups involved on certain aspects of mineralogical practice and facilitates interactions among mineralogists by sponsoring and organising meetings. In particular, the IMA holds its general meeting every four years. The next meeting is scheduled in 2022 in Lyon, France. Presidents The presidents of the IMA have been: * since 2021: Anhuai Lu ** Peking University *2018–2020: Patrick Cordier (born 1961) ** Université de Lille *2016–2018: Peter C. Burns ** University of Notre Dame *2014–2016: Sergey V. Krivovichev (born 1972) ** Saint Petersburg State University *2012–2014: Walter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uranyl Compounds
The uranyl ion is an oxycation In chemistry, an oxycation is a polyatomic ion with a positive charge that contains oxygen. Examples * Dioxygenyl ion, * Nitrosonium ion, * Nitronium ion, * Vanadyl ion, VO2+, a very stable oxycation * Uranyl ion, , all natural U6+ occurs in t ... of uranium in the oxidation state +6, with the chemical formula . It has a linear structure with short U–O bonds, indicative of the presence of multiple bonds between uranium and oxygen. Four or more ligands may be bound to the uranyl ion in an equatorial plane around the uranium atom. The uranyl ion forms many complex (chemistry), complexes, particularly with ligands that have oxygen donor atoms. Complexes of the uranyl ion are important in the extraction of uranium from its ores and in nuclear fuel reprocessing. Structure and bonding The uranyl ion is linear and symmetrical, with both U–O bond lengths of about 180 pm. The bond lengths are indicative of the presence of multiple bonding between ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uranium(VI) Minerals
Uranium is a chemical element with the Symbol (chemistry), symbol U and atomic number 92. It is a silvery-grey metal in the actinide series of the periodic table. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons. Uranium is weakly radioactive decay, radioactive because all isotopes of uranium are unstable; the half-lives of its naturally occurring isotopes range between 159,200 years and 4.5 billion years. The most common isotopes in natural uranium are uranium-238 (which has 146 neutrons and accounts for over 99% of uranium on Earth) and uranium-235 (which has 143 neutrons). Uranium has the highest atomic weight of the primordial nuclide, primordially occurring elements. Its density is about 70% higher than that of lead, and slightly lower than that of gold or tungsten. It occurs naturally in low concentrations of a few Parts-per notation#Parts-per expressions, parts per million in soil, rock and water, and is commercially uranium mining, ext ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Baden-Württemberg
Baden-Württemberg (; ), commonly shortened to BW or BaWü, is a German state () in Southwest Germany, east of the Rhine, which forms the southern part of Germany's western border with France. With more than 11.07 million inhabitants across a total area of nearly , it is the third-largest German state by both area (behind Bavaria and Lower Saxony) and population (behind North Rhine-Westphalia and Bavaria). As a federated state, Baden-Württemberg is a partly-sovereign parliamentary republic. The largest city in Baden-Württemberg is the state capital of Stuttgart, followed by Mannheim and Karlsruhe. Other major cities are Freiburg im Breisgau, Heidelberg, Heilbronn, Pforzheim, Reutlingen, Tübingen, and Ulm. What is now Baden-Württemberg was formerly the historical territories of Baden, Prussian Hohenzollern, and Württemberg. Baden-Württemberg became a state of West Germany in April 1952 by the merger of Württemberg-Baden, South Baden, and Württemberg-Hohenzollern. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Schenkenzell
Schenkenzell is a village in the district of Rottweil, in Baden-Württemberg, Germany. The town is twinned with Schenkon Schenkon is a municipality in the district of Sursee in the canton of Lucerne in Switzerland. Geography Schenkon has an area of . Of this area, 67.8% is used for agricultural purposes, while 17% is forested. Of the rest of the land, 14.8% is set ... in Switzerland. References External links Schenkenzell pictures Rottweil (district) {{Rottweil-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wittichen
Wittichen is a village that belongs to Kaltbrunn in the municipality of Schenkenzell in the district of Rottweil in the southwest German state of Baden-Württemberg. History In 1291, Luitgard, later the founder of the convent of Wittichen Abbey, was born in Wittichen. The abbey was founded in 1324. In 1498 Wittichen fell into the hands of the Swabian princes of Fürstenberg. The first attempt to close the convent was in 1540. In 1643 it was destroyed and its rebuilding took until 1681. During the Napoleonic era, Wittichen was secularised in 1803 and went to the Grand Duchy of Baden in 1806. Economy There was mining in Wittichen for centuries. Sights * Wittichen Abbey with its convent museum, exhibits on the history of the monastery and mining * Several spoil heaps from the days of mining still exist and some are accessible * Geological Educational Path, Wittichen Trails * Hansjakob Way I * Gengenbach–Alpirsbach Trail Events On the second Sunday in October i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Composition
A chemical composition specifies the identity, arrangement, and ratio of the elements making up a compound. Chemical formulas can be used to describe the relative amounts of elements present in a compound. For example, the chemical formula for water is H2O: this means that each molecule of water is constituted by 2 atoms of hydrogen (H) and 1 atom of oxygen (O). The chemical composition of water may be interpreted as a 2:1 ratio of hydrogen atoms to oxygen atoms. Different types of chemical formulas are used to convey composition information, such as an empirical or molecular formula. Nomenclature can be used to express not only the elements present in a compound but their arrangement within the molecules of the compound. In this way, compounds will have unique names which can describe their elemental composition. Composite mixture The chemical composition of a mixture can be defined as the distribution of the individual substances that constitute the mixture, called "compon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atom
Every atom is composed of a nucleus and one or more electrons bound to the nucleus. The nucleus is made of one or more protons and a number of neutrons. Only the most common variety of hydrogen has no neutrons. Every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. Atoms are extremely small, typically around 100 picometers across. They are so small that accurately predicting their behavior using classical physics, as if they were tennis balls for example, is not possible due to quantum effects. More than 99.94% of an atom's mass is in the nucleus. The protons have a positive electric charge, the electrons have a negative electric charge, and the neutrons have no electric charge. If the number of protons and electrons are equal, then the atom is electrically neutral. If an atom has more or fewer electrons than protons, then it has an overall negative or positive charge, respectively – such atoms are called ions. The electrons of an atom are a ... [...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] |
Radioactive Decay
Radioactive decay (also known as nuclear decay, radioactivity, radioactive disintegration, or nuclear disintegration) is the process by which an unstable atomic nucleus loses energy by radiation. A material containing unstable nuclei is considered radioactive. Three of the most common types of decay are alpha decay ( ), beta decay ( ), and gamma decay ( ), all of which involve emitting one or more particles. The weak force is the mechanism that is responsible for beta decay, while the other two are governed by the electromagnetism and nuclear force. A fourth type of common decay is electron capture, in which an unstable nucleus captures an inner electron from one of the electron shells. The loss of that electron from the shell results in a cascade of electrons dropping down to that lower shell resulting in emission of discrete X-rays from the transitions. A common example is iodine-125 commonly used in medical settings. Radioactive decay is a stochastic (i.e. random) proce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
