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Kassite (mineral)
Kassite is a rare mineral whose chemical formula is CaTi2O4(OH)2. It crystallizes in the orthorhombic crystal system and forms radiating rosettes and pseudo-hexagonal tabular crystals which are commonly Crystal twinning, twinned. Kassite crystals are brownish pink to pale yellow in color, are translucent, and have an adamantine luster. Cleavage is distinctly visible, and the crystals are very brittle. It was first described in 1965 in the Afrikanda pyroxenite massif, a formation on Russia's Kola Peninsula and was named for Nikolai Grigorievich Kassin (1885–1949), a prominent Russian geologist. It occurs as miarolitic, miarolytic cavity fillings of alkalic pegmatites in the Kola occurrence and in nepheline syenite in the Magnet Cove igneous complex of Arkansas, US. Its mineral association includes cafetite (which with it is also polymorphous), perovskite, titanite, rutile and ilmenite. References Oxide minerals Monoclinic minerals Minerals in space group 14 {{oxide-miner ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cafetite
Cafetite is a rare titanium oxide mineral with formula ·. It is named for its composition, Ca-Fe-Ti. It was first described in 1959 for an occurrence in the Afrikanda Massif, Afrikanda (rural locality), Afrikanda, Kola Peninsula, Murmanskaja Oblast, Northern Region, Russia. It is also reported from the Khibiny Massif, Khibiny and Kovdor Massif, Kovdor massifs of the Kola Peninsula and from Meagher County, Montana, US. It occurs in pegmatites in a pyroxenite intrusion as crystals in Miarolitic cavity, miarolitic cavities. It occurs associated with ilmenite, titaniferous magnetite, titanite, anatase, perovskite, baddeleyite, phlogopite, Chlorite group, clinochlore and Kassite (mineral), kassite. References Oxide minerals Titanium minerals Monoclinic minerals Minerals in space group 14 {{oxide-mineral-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Miarolitic
Miarolitic cavities (or ''miarolitic texture'') are typically crystal-lined irregular cavities or vugs most commonly found in granitic pegmatites, and also in a variety of igneous rocks. The central portions of pegmatites are often miarolitic as the pegmatite dike crystallizes from the outside walls toward the center. The volatile portion of the magma is gradually excluded from the forming crystal phases until it becomes trapped within the body and forms the cavities which often contain minerals of elements incompatible with the typical silicate granitic mineralogy. The miarolitic cavities and miarolitic pegmatites are sources of rare and unusual minerals containing elements not found in abundance in normal igneous rocks. Minerals containing lithium, rubidium, beryllium, boron, niobium, tantalum, tin, bismuth, fluorine and other elements can be found. The term ''miarolitic'' comes from the Italian Italian(s) may refer to: * Anything of, from, or related to the people of Italy ov ... [...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] |
Ilmenite
Ilmenite is a titanium-iron oxide mineral with the idealized formula . It is a weakly magnetic black or steel-gray solid. Ilmenite is the most important ore of titanium and the main source of titanium dioxide, which is used in paints, printing inks, fabrics, plastics, paper, sunscreen, food and cosmetics. Structure and properties Ilmenite is a heavy (specific gravity 4.7), moderately hard (Mohs hardness 5.6 to 6), opaque black mineral with a submetallic luster. It is almost always massive, with thick tabular crystals being quite rare. It shows no discernible cleavage, breaking instead with a conchoidal to uneven fracture. Ilmenite crystallizes in the trigonal system with space group ''R''. The ilmenite crystal structure consists of an ordered derivative of the corundum structure; in corundum all cations are identical but in ilmenite Fe2+ and Ti4+ ions occupy alternating layers perpendicular to the trigonal c axis. Pure ilmenite is paramagnetic (showing only very weak attrac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rutile
Rutile is an oxide mineral composed of titanium dioxide (TiO2), the most common natural form of TiO2. Rarer Polymorphism (materials science), polymorphs of TiO2 are known, including anatase, akaogiite, and brookite. Rutile has one of the highest refractive index, refractive indices at visible wavelengths of any known crystal and also exhibits a particularly large birefringence and high dispersion (optics), dispersion. Owing to these properties, it is useful for the manufacture of certain optical elements, especially Polarization (waves), polarization optics, for longer light, visible and infrared, infrared wavelengths up to about 4.5 micrometres. Natural rutile may contain up to 10% iron and significant amounts of niobium and tantalum. Rutile derives its name from the Latin ('red'), in reference to the deep red color observed in some specimens when viewed by transmitted light. Rutile was first described in 1803 by Abraham Gottlob Werner. Occurrence Rutile is a common accessory ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Titanite
Titanite, or sphene (from the Greek ''sphenos'' (σφηνώ), meaning wedge), is a calcium titanium nesosilicate mineral, Ca Ti Si O5. Trace impurities of iron and aluminium are typically present. Also commonly present are rare earth metals including cerium and yttrium; calcium may be partly replaced by thorium. Nomenclature The International Mineralogical Association Commission on New Minerals and Mineral Names (CNMMN) adopted the name titanite and "discredited" the name sphene as of 1982, although commonly papers and books initially identify the mineral using both names. Sphene was the most commonly used name until the IMA decision, although both were well known. Some authorities think it is less confusing as the word is used to describe any chemical or crystal with oxidized titanium such as the rare earth titanate pyrochlores series and many of the minerals with the perovskite structure. The name sphene continues to be publishable in peer-reviewed scientific literature, e.g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perovskite
Perovskite (pronunciation: ) is a calcium titanium oxide mineral composed of calcium titanate (chemical formula ). Its name is also applied to the class of compounds which have the same type of crystal structure as (XIIA2+VIB4+X2−3), known as the perovskite structure. Many different cations can be embedded in this structure, allowing the development of diverse engineered materials. History The mineral was discovered in the Ural Mountains of Russia by Gustav Rose in 1839 and is named after Russian mineralogist Lev Perovski (1792–1856). Perovskite's notable crystal structure was first described by Victor Goldschmidt in 1926 in his work on tolerance factors. The crystal structure was later published in 1945 from X-ray diffraction data on barium titanate by Helen Dick Megaw. Occurrence Found in the Earth's mantle, perovskite's occurrence at Khibina Massif is restricted to the silica under-saturated ultramafic rocks and foidolites, due to the instability in a paragenesis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arkansas
Arkansas ( ) is a landlocked state in the South Central United States. It is bordered by Missouri to the north, Tennessee and Mississippi to the east, Louisiana to the south, and Texas and Oklahoma to the west. Its name is from the Osage language, a Dhegiha Siouan language, and referred to their relatives, the Quapaw people. The state's diverse geography ranges from the mountainous regions of the Ozark and Ouachita Mountains, which make up the U.S. Interior Highlands, to the densely forested land in the south known as the Arkansas Timberlands, to the eastern lowlands along the Mississippi River and the Arkansas Delta. Arkansas is the 29th largest by area and the 34th most populous state, with a population of just over 3 million at the 2020 census. The capital and most populous city is Little Rock, in the central part of the state, a hub for transportation, business, culture, and government. The northwestern corner of the state, including the Fayetteville–Springdaleâ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnet Cove Igneous Complex
The Magnet Cove igneous complex is a small alkalic ring complex lying to the west of the town of Magnet Cove in Hot Spring County, Arkansas.Geology of Titanium-Mineral Deposits, Eric R. Force, Geological Society of America, 1991,Google Books/ref> It and the adjacent town are so named due to the existence of magnetite and the terrain being a cove, a basin-shaped valley. The complex is of Mesozoic age, intruded into Paleozoic sediments. Mapping was conducted by the geologists Erickson and Blade in 1963. Units within the complex include carbonatite, nepheline syenite, phonolite, and ijolite. In addition to the magnetite which forms both massive lodestone and crystals, the complex is strewn with odd and rare minerals, and is the type locality for five mineral species. Over 100 different minerals have been identified from the area. There are many titanium minerals such as rutile, anatase, brookite, and perovskite, as well as some vanadium mineralization. Some rare-earth-bearing m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nepheline Syenite
Nepheline syenite is a holocrystalline plutonic rock that consists largely of nepheline and alkali feldspar. The rocks are mostly pale colored, grey or pink, and in general appearance they are not unlike granites, but dark green varieties are also known. Phonolite is the fine-grained extrusive equivalent. Petrology Nepheline syenites are silica-undersaturated and some are peralkaline (terms discussed in igneous rock). Nepheline is a feldspathoid, a solid-solution mineral, that does not coexist with quartz; rather, nepheline would react with quartz to produce alkali feldspar. They are distinguished from ordinary basic syenites not only by the presence of nepheline but also by the occurrence of many other minerals rich in alkalis and in rare earths and other incompatible elements. Alkali feldspar dominates, commonly represented by orthoclase and the exsolved lamellar albite, form perthite. In some rocks the potash feldspar, in others the soda feldspar predominates. Fresh clear m ... [...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] |
Nikolai Grigorievich Kassin
Nikolai or Nikolay is an East Slavic variant of the masculine name Nicholas. It may refer to: People Royalty * Nicholas I of Russia (1796–1855), or Nikolay I, Emperor of Russia from 1825 until 1855 * Nicholas II of Russia (1868–1918), or Nikolay II, last Emperor of Russia, from 1894 until 1917 * Prince Nikolai of Denmark (born 1999) Other people Nikolai * Nikolai Aleksandrovich (other) or Nikolay Aleksandrovich, several people * Nikolai Antropov (born 1980), Kazakh former ice hockey winger * Nikolai Berdyaev (1874-1948), Russian religious and political philosopher * Nikolai Bogomolov (born 1991), Russian professional ice hockey defenceman * Nikolai Bukharin (1888–1938), Bolshevik revolutionary and Soviet politician * Nikolai Bulganin (1895-1975), Soviet politician and minister of defence * Nikolai Chernykh (1931-2004), Russian astronomer * Nikolai Dudorov (1906–1977), Soviet politician * Nikolai Dzhumagaliev (born 1952), Soviet serial killer * Nikolai Goc (born ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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