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Elsmoreite
Hydrokenoelsmoreite is a hydrous tungsten oxide mineral with formula □2W2O6(H2O). Hydrokenoelsmoreite is a colorless to white, translucent isometric mineral. It has a Mohs hardness of 3, exhibits no cleavage and has a splintery fracture. It has a vitreous to adamantine luster. It is optically isotropic with an index of refraction of n = 2.24. It forms from the oxidation of ferberite within granitic pegmatite dykes and in pegmatitic greisen veins. It has a structure based on a defect pyrochlore lattice (A2B2O6O’). It was first described for an occurrence in Elsmore Hill, New South Wales ) , nickname = , image_map = New South Wales in Australia.svg , map_caption = Location of New South Wales in AustraliaCoordinates: , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , es ..., Australia from where it takes its name. References *Williams, P.A., Leverett, P., Sharpe, J.L., Colchester, D.M. (2005): Elsmoreite, cu ... [...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] |
Stolzite
Stolzite is a mineral, a lead tungstate; with the formula Pb W O4. It is similar to, and often associated with, wulfenite which is the same chemical formula except that the tungsten is replaced by molybdenum. Stolzite crystallizes in the tetragonal crystal system and is dimorphous with the monoclinic form raspite. Lead tungstate crystals have the optical transparency of glass combined with much higher density (8.28 g/cm3 vs ~2.2 g/cm3 for fused silica). They are used as scintillators in particle physics because of their short radiation length (0.89 cm), low Molière radius (2.2 cm), quick scintillation response, and radiation hardness. Lead tungstate crystals are used in the Compact Muon Solenoid's electromagnetic calorimeter. It was first described in 1820 by August Breithaupt, who called it Scheelbleispath and then by François Sulpice Beudant in 1832, who called it scheelitine. In 1845, Wilhelm Karl Ritter von Haidinger coined the name stolzite for a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tungsten Minerals
Tungsten, or wolfram, is a chemical element with the symbol W and atomic number 74. Tungsten is a rare metal found naturally on Earth almost exclusively as compounds with other elements. It was identified as a new element in 1781 and first isolated as a metal in 1783. Its important ores include scheelite and wolframite, the latter lending the element its alternate name. The free element is remarkable for its robustness, especially the fact that it has the highest melting point of all known elements barring carbon (which sublimes at normal pressure), melting at . It also has the highest boiling point, at . Its density is , comparable with that of uranium and gold, and much higher (about 1.7 times) than that of lead. Polycrystalline tungsten is an intrinsically brittle and hard material (under standard conditions, when uncombined), making it difficult to work. However, pure single-crystalline tungsten is more ductile and can be cut with a hard-steel hacksaw. Tungsten occurs in m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Australia
Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, smaller islands. With an area of , Australia is the largest country by area in Oceania and the world's List of countries and dependencies by area, sixth-largest country. Australia is the oldest, flattest, and driest inhabited continent, with the least fertile soils. It is a Megadiverse countries, megadiverse country, and its size gives it a wide variety of landscapes and climates, with Deserts of Australia, deserts in the centre, tropical Forests of Australia, rainforests in the north-east, and List of mountains in Australia, mountain ranges in the south-east. The ancestors of Aboriginal Australians began arriving from south east Asia approximately Early human migrations#Nearby Oceania, 65,000 years ago, during the Last Glacial Period, last i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
New South Wales
) , nickname = , image_map = New South Wales in Australia.svg , map_caption = Location of New South Wales in AustraliaCoordinates: , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , established_date = Colony of New South Wales , established_title2 = Establishment , established_date2 = 26 January 1788 , established_title3 = Responsible government , established_date3 = 6 June 1856 , established_title4 = Federation , established_date4 = 1 January 1901 , named_for = Wales , demonym = , capital = Sydney , largest_city = capital , coordinates = , admin_center = 128 local government areas , admin_center_type = Administration , leader_title1 = Monarch , leader_name1 = Charles III , leader_title2 = Governor , leader_name2 = Margaret Beazley , leader_title3 = Premier , leader_name3 = Dominic Perrottet (Liberal) , national_representation = Parliament of Australia , national_representation_type1 = Senat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crystal Structure
In crystallography, crystal structure is a description of the ordered arrangement of atoms, ions or molecules in a crystal, crystalline material. Ordered structures occur from the intrinsic nature of the constituent particles to form symmetric patterns that repeat along the principal directions of Three-dimensional space (mathematics), three-dimensional space in matter. The smallest group of particles in the material that constitutes this repeating pattern is the unit cell of the structure. The unit cell completely reflects the symmetry and structure of the entire crystal, which is built up by repetitive Translation (geometry), translation of the unit cell along its principal axes. The translation vectors define the nodes of the Bravais lattice. The lengths of the principal axes, or edges, of the unit cell and the angles between them are the lattice constants, also called ''lattice parameters'' or ''cell parameters''. The symmetry properties of the crystal are described by the con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyrochlore
Pyrochlore () is a mineral group of the niobium end member of the pyrochlore supergroup. The general formula, (where A and B are metals), represent a family of phases isostructural to the mineral pyrochlore. Pyrochlores are an important class of materials in diverse technological applications such as luminescence, ionic conductivity, nuclear waste immobilization, high temperature thermal barrier coatings, automobile exhaust gas control, catalysts, solid oxide fuel cell, ionic/electrical conductors etc. Occurrence The mineral is associated with the metasomatic end stages of magmatic intrusions. Pyrochlore crystals are usually well formed (euhedral), occurring usually as octahedra of a yellowish or brownish color and resinous luster. It is commonly metamict due to radiation damage from included radioactive elements. Pyrochlore occurs in pegmatites associated with nepheline syenites and other alkalic rocks. It is also found in granite pegmatites and greisens. It is characteristical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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] |
Greisen
Greisen is a highly altered granitic rock or pegmatite, usually composed predominantly of quartz and micas (mostly muscovite). Greisen is formed by self-generated alteration of a granite and is a class of moderate- to high-temperature magmatic-hydrothermal alteration related to the late-stage release of volatiles dissolved in a magma during the solidification of that magma. Greisens are usually variably altered rocks, grading from coarse, crystalline granite, commonly vuggy with miarolitic cavities, through to quartz and muscovite rich rocks, which may be locally rich in topaz, tourmaline, cassiterite, fluorite, beryl, wolframite, siderite, molybdenite and other sulfide minerals, and other accessory minerals. They may occur as small to large veins, or large zones in the roof of some granites. The rocks can sometimes be mined as ores of tin and other minerals. Petrogenesis Greisens are formed by endogenous alteration of granite during the cooling stages of emplacement. Greisen f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dike (geology)
A dike or dyke, in Geology, geological usage, is a sheet of rock that is formed in a Fracture (geology), fracture of a pre-existing rock body. Dikes can be either Intrusive rock, magmatic or Sedimentary rock, sedimentary in origin. Magmatic dikes form when magma flows into a crack then solidifies as a sheet intrusion, either cutting across layers of rock or through a contiguous mass of rock. Clastic dikes are formed when sediment fills a pre-existing crack.Essentials of Geology, 3rd Ed, Stephen Marshak Magmatic dikes A magmatic dike is a sheet of igneous rock that cuts across older rock beds. It is formed when magma fills a fracture in the older beds and then cools and solidifies. The dike rock is usually more resistant to weathering than the surrounding rock, so that erosion exposes the dike as a natural wall or ridge. It is from these natural walls that dikes get their name. Dikes preserve a record of the fissures through which most mafic magma (fluid magma low in silica) reac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ferberite
Ferberite is the iron endmember of the manganese - iron wolframite solid solution series. The manganese endmember is hübnerite. Ferberite is a black monoclinic mineral composed of iron(II) tungstate, Fe W O4. Ferberite and hübnerite often contain both divalent cations of iron and manganese, with wolframite as the intermediate species for which the solid solution series is named. Ferberite occurs as granular masses and as slender prismatic crystals. It has a Mohs hardness of 4.5 and a specific gravity of 7.4 to 7.5. Ferberite typically occurs in pegmatites, granitic greisens, and high temperature hydrothermal deposits. It is a minor ore of tungsten. Ferberite was discovered in 1863 in Sierra Almagrera, Spain, and named after the German mineralogist Moritz Rudolph Ferber (1805–1875). File:Ferberite-49138.jpg, Twinned Ferberite, Tazna Mine, Atocha-Quechisla District, Nor Chichas Province, Potosí Department, Bolivia. 4.8 x 4.0 x 3.6 cm. Image:Ferbèrite-Tchéquie.jpg, F ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pegmatite
A pegmatite is an igneous rock showing a very coarse texture, with large interlocking crystals usually greater in size than and sometimes greater than . Most pegmatites are composed of quartz, feldspar, and mica, having a similar silicic composition to granite. However, rarer intermediate composition and mafic pegmatites are known. Many of the world's largest crystals are found within pegmatites. These include crystals of microcline, quartz, mica, spodumene, beryl, and tourmaline. Some individual crystals are over long. Most pegmatites are thought to form from the last fluid fraction of a large crystallizing magma body. This residual fluid is highly enriched in volatiles and trace elements, and its very low viscosity allows molecules to migrate rapidly to join an existing crystal rather than coming together to form new crystals. This allows a few very large crystals to form. While most pegmatites have a simple composition of minerals common in ordinary igneous rock, a few ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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