Cryptomelane

	Cryptomelane Cryptomelane is a potassium manganese oxide mineral with formula K(Mn4+,Mn2+)8O16. In 1942 the name ''cryptomelane'' was proposed as part of an effort to sort out the manganese oxide minerals referred to as ''psilomelane''. Cryptomelane was identified and defined based on X-ray diffraction studies of samples from Tombstone, Arizona; Deming, New Mexico; Mena, Arkansas; and Philipsburg, Montana. Cryptomelane was approved in 1982 by the International Mineralogical Association (IMA). The Type locality (geology), type locality is the Tombstone District, Cochise County, Arizona, US. The name comes from the Greek (language), Greek for hidden and black, in reference to the confusion and difficulty in recognition of the various black manganese oxide minerals referred to as ''psilomelane'', the collective term for hard manganese oxides. It is of rather common occurrence in Redox, oxidized manganese deposits where it occurs as replacements and open space fillings in Vein (geology), veins an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Oxide Mineral The oxide mineral class includes those minerals in which the oxide anion (O2−) is bonded to one or more metal alloys. The hydroxide-bearing minerals are typically included in the oxide class. The minerals with complex anion groups such as the silicates, sulfates, carbonates and phosphates are classed separately. Simple oxides: XO Periclase group Periclase Manganosite Zincite group Zincite * Bromellite *Tenorite Litharge Cuprite Ice * Hematite group Corundum Hematite Ilmenite Rutile group Rutile Pyrolusite Cassiterite Baddeleyite Uraninite Thorianite Spinel group Spinel Gahnite Magnetite Franklinite Chromite Chrysoberyl Columbite Hydroxide subgroup: Brucite Manganite Romanèchite Goethite group: *Diaspore Goethite Nickel–Strunz Classification -04- Oxides IMA-CNMNC proposes a new hierarchical scheme (Mills et al., 2009). This list uses it to modify ... [...More Info...] [...Related Items...] OR:* [Wikipedia] [Google] [Baidu]
	Oxide Minerals The oxide mineral class includes those minerals in which the oxide anion (O2−) is bonded to one or more metal alloys. The hydroxide-bearing minerals are typically included in the oxide class. The minerals with complex anion groups such as the silicates, sulfates, carbonates and phosphates are classed separately. Simple oxides: XO Periclase group Periclase Manganosite Zincite group Zincite * Bromellite *Tenorite Litharge Cuprite Ice * Hematite group Corundum Hematite Ilmenite Rutile group Rutile Pyrolusite * Cassiterite Baddeleyite Uraninite *Thorianite Spinel group Spinel Gahnite Magnetite Franklinite * Chromite Chrysoberyl Columbite Hydroxide subgroup: Brucite Manganite * Romanèchite Goethite group: Diaspore Goethite Nickel–Strunz Classification -04- Oxides IMA-CNMNC proposes a new hierarchical scheme (Mills et al., 2009). This list uses it to mod ... [...More Info...] [...Related Items...] OR:** [Wikipedia] [Google] [Baidu]
	Oxide Mineral The oxide mineral class includes those minerals in which the oxide anion (O2−) is bonded to one or more metal alloys. The hydroxide-bearing minerals are typically included in the oxide class. The minerals with complex anion groups such as the silicates, sulfates, carbonates and phosphates are classed separately. Simple oxides: XO Periclase group Periclase Manganosite Zincite group Zincite * Bromellite *Tenorite Litharge Cuprite Ice * Hematite group Corundum Hematite Ilmenite Rutile group Rutile Pyrolusite Cassiterite Baddeleyite Uraninite Thorianite Spinel group Spinel Gahnite Magnetite Franklinite Chromite Chrysoberyl Columbite Hydroxide subgroup: Brucite Manganite Romanèchite Goethite group: *Diaspore Goethite Nickel–Strunz Classification -04- Oxides IMA-CNMNC proposes a new hierarchical scheme (Mills et al., 2009). This list uses it to modify ... [...More Info...] [...Related Items...] OR:* [Wikipedia] [Google] [Baidu]
picture info	Greek (language) Greek ( el, label=Modern Greek, Ελληνικά, Elliniká, ; grc, Ἑλληνική, Hellēnikḗ) is an independent branch of the Indo-European family of languages, native to Greece, Cyprus, southern Italy ( Calabria and Salento), southern Albania, and other regions of the Balkans, the Black Sea coast, Asia Minor, and the Eastern Mediterranean. It has the 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 alphabet arose from the Phoenician script and was in turn the basis of the Latin, Cyrillic, Armenian, Coptic, Gothic, and many other writing systems. 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 im ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Manganese(II,IV) Minerals Manganese is a chemical element with the symbol Mn and atomic number 25. It is a hard, brittle, silvery metal, often found in minerals in combination with iron. Manganese is a transition metal with a multifaceted array of industrial alloy uses, particularly in stainless steels. It improves strength, workability, and resistance to wear. Manganese oxide is used as an oxidising agent; as a rubber additive; and in glass making, fertilisers, and ceramics. Manganese sulfate can be used as a fungicide. Manganese is also an essential human dietary element, important in macronutrient metabolism, bone formation, and free radical defense systems. It is a critical component in dozens of proteins and enzymes. It is found mostly in the bones, but also the liver, kidneys, and brain. In the human brain, the manganese is bound to manganese metalloproteins, most notably glutamine synthetase in astrocytes. Manganese was first isolated in 1774. It is familiar in the laboratory in the form of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Manganite Manganite is a mineral composed of manganese oxide-hydroxide, MnO(OH), crystallizing in the monoclinic system (pseudo-orthorhombic). Crystals of manganite are prismatic and deeply striated parallel to their length; they are often grouped together in bundles. The color is dark steel-grey to iron-black, and the luster brilliant and submetallic. The streak is dark reddish brown. The hardness is 4, and the specific gravity is 4.3. There is a perfect cleavage parallel to the brachypinacoid, and less-perfect cleavage parallel to the prism faces. Twinned crystals are not infrequent. The mineral contains 89.7% manganese sesquioxide; it dissolves in hydrochloric acid with evolution of chlorine. Occurrence Manganite occurs with other manganese oxides in deposits formed by circulating meteoric water in the weathering environment in clay deposits and laterites. It forms by low temperature hydrothermal action in veins in association with calcite, barite, and siderite. Often associated wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Braunite Braunite is a silicate mineral containing both di- and tri- valent manganese with the chemical formula: Mn2+Mn3+6 SiO4 Common impurities include iron, calcium, boron, barium, titanium, aluminium, and magnesium. Braunite forms grey/black tetragonal crystals and has a Mohs hardness of 6 - 6.5. It was named after the Wilhelm von Braun (1790–1872) of Gotha, Thuringia, Germany. A calcium iron bearing variant, named braunite II (formula: Ca(Mn3+,Fe3+)14SiO24), was discovered and described in 1967 from Kalahari, Cape Province, South Africa South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. It is bounded to the south by of coastline that stretch along the South Atlantic and Indian Oceans; to the north by the neighbouring countri .... References External linksWebmineralAthena mineral ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Nsutite Nsutite is a manganese oxide mineral with formula: ( Mn4+1−xMn2+x O2-2x(O H)2x where x = 0.06-0.07).http://www.webmineral.com/data/Nsutite.shtml Webmineral data It is found in most large manganese deposits and was first discovered in Nsuta, Ghana. Since then, it has been found worldwide. Nsutite is a dull mineral with a hardness of 6.5-8.5 and an average specific gravity of 4.45. Nustite is used as a cathode A cathode is the electrode from which a conventional current leaves a polarized electrical device. This definition can be recalled by using the mnemonic ''CCD'' for ''Cathode Current Departs''. A conventional current describes the direction in wh ... in zinc–carbon batteries, but synthetic manganese oxide is gradually replacing it. References Oxide minerals Manganese(II,IV) minerals Hexagonal minerals {{oxide-mineral-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Pyrolusite Pyrolusite is a mineral consisting essentially of manganese dioxide ( Mn O2) and is important as an ore of manganese.. It is a black, amorphous appearing mineral, often with a granular, fibrous, or columnar structure, sometimes forming reniform crusts. It has a metallic luster, a black or bluish-black streak, and readily soils the fingers. The specific gravity is about 4.8. Its name is from the Greek for ''fire'' and to ''wash'', in reference to its use as a way to remove tints from glass. Occurrence Pyrolusite and romanechite are among the most common manganese minerals. Pyrolusite occurs associated with manganite, hollandite, hausmannite, braunite, chalcophanite, goethite, and hematite under oxidizing conditions in hydrothermal deposits. It also occurs in bogs and often results from alteration of manganite. Use The metal is obtained by reduction of the oxide with sodium, magnesium, aluminium, or by electrolysis. Pyrolusite is extensively used for the manufacture of spi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Vein (geology) In geology, a vein is a distinct sheetlike body of crystallized minerals within a rock. Veins form when mineral constituents carried by an aqueous solution within the rock mass are deposited through precipitation. The hydraulic flow involved is usually due to hydrothermal circulation. Veins are classically thought of as being the ones in the body not the rock veins and arteries planar fractures in rocks, with the crystal growth occurring normal to the walls of the cavity, and the crystal protruding into open space. This certainly is the method for the formation of some veins. However, it is rare in geology for significant open space to remain open in large volumes of rock, especially several kilometers below the surface. Thus, there are two main mechanisms considered likely for the formation of veins: ''open-space filling'' and ''crack-seal growth''. Open space filling Open space filling is the hallmark of epithermal vein systems, such as a stockwork, in greisens or in cert ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Redox Redox (reduction–oxidation, , ) is a type of chemical reaction in which the oxidation states of substrate (chemistry), substrate change. Oxidation is the loss of Electron, electrons or an increase in the oxidation state, while reduction is the gain of electrons or a decrease in the oxidation state. There are two classes of redox reactions: * ''Electron-transfer'' – Only one (usually) electron flows from the reducing agent to the oxidant. This type of redox reaction is often discussed in terms of redox couples and electrode potentials. * ''Atom transfer'' – An atom transfers from one substrate to another. For example, in the rusting of iron, the oxidation state of iron atoms increases as the iron converts to an oxide, and simultaneously the oxidation state of oxygen decreases as it accepts electrons released by the iron. Although oxidation reactions are commonly associated with the formation of oxides, other chemical species can serve the same function. In hydrogen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]