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Sheldrickite
Sheldrickite is a sodium calcium carbonate fluoride mineral, named in honor of George M. Sheldrick, former Professor of Crystallography at the University of Göttingen in Germany. Sheldrick is the creator of SHELX computer program widely used for the analysis of crystal structures. Determination of the structure of this mineral required the software's capability of handling twinned crystals. Occurrence Sheldrickite is a rare mineral found in Mont Saint-Hilaire, Canada. Mont Saint-Hilaire is an alkaline intrusive complex and one of the ten Monteregian Hills. A series of plutons is aligned along the St. Lawrence Valley for almost 150 km eastward from Oka to Megantic. Sheldrickite is closely associated with shortite (), with the crystals being found in a cavity between shortite crystals. Sheldrickite also occurs as flakes in thin seams between crystals of shortite. Sheldrickite is thought to be formed in a late-stage hydrothermal infilling. The associated species of Sheldrickite ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbonates
A carbonate is a salt of carbonic acid, (), characterized by the presence of the carbonate ion, a polyatomic ion with the formula . The word "carbonate" may also refer to a carbonate ester, an organic compound containing the carbonate group . The term is also used as a verb, to describe carbonation: the process of raising the concentrations of carbonate and bicarbonate ions in water to produce carbonated water and other carbonated beverageseither by the addition of carbon dioxide gas under pressure or by dissolving carbonate or bicarbonate salts into the water. In geology and mineralogy, the term "carbonate" can refer both to carbonate minerals and carbonate rock (which is made of chiefly carbonate minerals), and both are dominated by the carbonate ion, . Carbonate minerals are extremely varied and ubiquitous in chemically precipitated sedimentary rock. The most common are calcite or calcium carbonate, , the chief constituent of limestone (as well as the main component of mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polylithionite
Lepidolite is the common name for a lilac-gray or rose-colored series of minerals in the mica group. The mineralogical name for this series is the polylithionite-trilithionite series. Lepidolite has a chemical formula of . It is the most abundant lithium-bearing mineral and is a secondary source of this metal. It is the major source of the alkali metal rubidium. Lepidolite is found with other lithium-bearing minerals, such as spodumene, in pegmatite bodies. It has also been found in high-temperature quartz veins, greisens and granite. Description Lepidolite is a phyllosilicate mineral and a member of the polylithionite-trilithionite series. Lepidolite is part of a three-part series consisting of polylithionite, lepidolite, and trilithionite. All three minerals share similar properties and are caused because of varying ratios of lithium and aluminum in their chemical formulas. The Li:Al ratio varies from 2:1 in polylithionite up to 1.5:1.5 in trilithionite. Lepidolite is found n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kogarkoite
Kogarkoite is a sodium sulfate fluoride mineral with formula Na3(SO4)F. It has a pale blue color, a specific gravity of about 2.67 and a hardness of 3.5. The crystal is monoclinic and is a type of naturally occurring antiperovskite. Kogarkoite is named after the Russian petrologist Lia Nikolaevna Kogarko (born 1936) who discovered the mineral. Discovery and occurrence Kogarkoite was first described in 1973 for an occurrence on Alluaiv Mountain, Lovozero Massif, Kola Peninsula, Russia. On Alluaiv it occurs in pegmatitic veins in nepheline syenite. It occurs with sodalite in syenite xenoliths in an alkali intrusive complex at Mont Saint-Hilaire, Canada. In Hortense Hot Spring, Chaffee County, Colorado, it occurs as a sublimate. It occurs at Lake Natron near Ol Doinyo Lengai, Tanzania and Suswa Volcano, Lake Magadi, Kenya. See also *List of minerals *List of minerals named after people This is a list of minerals named after people. The chemical composition of the mineral foll ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galena
Galena, also called lead glance, is the natural mineral form of lead(II) sulfide (PbS). It is the most important ore of lead and an important source of silver. Galena is one of the most abundant and widely distributed sulfide minerals. It crystallizes in the Cubic (crystal system), cubic crystal system often showing octahedral forms. It is often associated with the minerals sphalerite, calcite and fluorite. As a pure specimen held in the hand, under standard temperature and pressure, galena is insoluble in water and so is almost non-toxic. Handling galena under these specific conditions (such as in a museum or as part of geology instruction) poses practically no risk; however, as lead(II) sulfide is reasonably reactive in a variety of environments, it can be highly toxic if swallowed or inhaled, particularly under prolonged or repeated exposure. Occurrence Galena is the main ore of lead, used since ancient times, since lead can be smelted from galena in an ordinary wood fire. G ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sphalerite
Sphalerite is a sulfide mineral with the chemical formula . It is the most important ore of zinc. Sphalerite is found in a variety of deposit types, but it is primarily in Sedimentary exhalative deposits, sedimentary exhalative, Carbonate-hosted lead-zinc ore deposits, Mississippi-Valley type, and Volcanogenic massive sulfide ore deposit, volcanogenic massive sulfide deposits. It is found in association with galena, chalcopyrite, pyrite (and other sulfide mineral, sulfides), calcite, dolomite (mineral), dolomite, quartz, rhodochrosite, and fluorite. German geologist Ernst Friedrich Glocker discovered sphalerite in 1847, naming it based on the Greek word ''sphaleros'', meaning "deceiving", due to the difficulty of identifying the mineral. In addition to zinc, sphalerite is an ore of cadmium, gallium, germanium, and indium. Miners have been known to refer to sphalerite as ''zinc blende'', ''black-jack'', and ''ruby blende''. Marmatite is an opaque black variety with a high iron ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermonatrite
Thermonatrite is a naturally occurring evaporite mineral form of sodium carbonate, Na2CO3·H2O. It was first described in 1845. Its name is from the Greek θερμός ''thermos'', "heat", plus ''natron'', because it may be a dehydration product of natron. Typical occurrence is in dry saline lake beds and as soil encrustations. It has been reported from volcano, volcanic fumaroles and in association with carbonatite-related Vein (geology), veins. Common associated minerals include trona, natron and halite. See also * Nahcolite * Natron * Niter * Potassium nitrate * Shortite * Soda (other) * Sodium sesquicarbonate * Trona References Carbonate minerals Orthorhombic minerals Minerals in space group 29 {{carbonate-mineral-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molybdenite
Molybdenite is a mineral of molybdenum disulfide, Mo S2. Similar in appearance and feel to graphite, molybdenite has a lubricating effect that is a consequence of its layered structure. The atomic structure consists of a sheet of molybdenum atoms sandwiched between sheets of sulfur atoms. The Mo-S bonds are strong, but the interaction between the sulfur atoms at the top and bottom of separate sandwich-like tri-layers is weak, resulting in easy slippage as well as cleavage planes. Molybdenite crystallizes in the hexagonal crystal system as the common polytype 2H and also in the trigonal system as the 3R polytype. Description Occurrence Molybdenite occurs in high temperature hydrothermal ore deposits. Its associated minerals include pyrite, chalcopyrite, quartz, anhydrite, fluorite, and scheelite. Important deposits include the disseminated porphyry molybdenum deposits at Questa, New Mexico and the Henderson and Climax mines in Colorado. Molybdenite also occurs in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluorite
Fluorite (also called fluorspar) is the mineral form of calcium fluoride, CaF2. It belongs to the halide minerals. It crystallizes in isometric cubic habit, although octahedral and more complex isometric forms are not uncommon. The Mohs scale of mineral hardness, based on scratch hardness comparison, defines value 4 as fluorite. Pure fluorite is colourless and transparent, both in visible and ultraviolet light, but impurities usually make it a colorful mineral and the stone has ornamental and lapidary uses. Industrially, fluorite is used as a flux for smelting, and in the production of certain glasses and enamels. The purest grades of fluorite are a source of fluoride for hydrofluoric acid manufacture, which is the intermediate source of most fluorine-containing fine chemicals. Optically clear transparent fluorite has anomalous partial dispersion, that is, its refractive index varies with the wavelength of light in a manner that differs from that of commonly used glasses, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcite
Calcite is a Carbonate minerals, carbonate mineral and the most stable Polymorphism (materials science), polymorph of calcium carbonate (CaCO3). It is a very common mineral, particularly as a component of limestone. Calcite defines hardness 3 on the Mohs scale of mineral hardness, based on Scratch hardness, scratch hardness comparison. Large calcite crystals are used in optical equipment, and limestone composed mostly of calcite has numerous uses. Other polymorphs of calcium carbonate are the minerals aragonite and vaterite. Aragonite will change to calcite over timescales of days or less at temperatures exceeding 300 °C, and vaterite is even less stable. Etymology Calcite is derived from the German , a term from the 19th century that came from the Latin word for Lime (material), lime, (genitive ) with the suffix ''-ite'' used to name minerals. It is thus a Doublet (linguistics), doublet of the word ''wikt:chalk, chalk''. When applied by archaeology, archaeologists and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
