Valentinite

picture info	Valentinite Valentinite is an antimony oxide mineral with formula Sb2 O3. Valentinite crystallizes in the orthorhombic system and typically forms as radiating clusters of euhedral crystals or as fibrous masses. It is colorless to white with occasional shades or tints of yellow and red. It has a Mohs hardness of 2.5 to 3 and a specific gravity of 5.76.Pradyot Patnaik. ''Handbook of Inorganic Chemicals''. McGraw-Hill, 2002, Valentinite occurs as a weathering product of stibnite and other antimony minerals. It is dimorphous with the isometric antimony oxide senarmontite. Historical data Valentinite is a mineral named in the middle of the 19th century in honour of Basilius Valentinus, a writer on alchemy. He is the supposed author of the first book to give a detailed description of antimony and its compounds. From the contents of the book it is also obvious that Valentinus was familiar with the synthetic preparation of antimony trioxide, which was called 'the antimony flower'. Valentinite w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Antimony Trioxide Antimony(III) oxide is the inorganic compound with the formula Sb2O3. It is the most important commercial compound of antimony. It is found in nature as the minerals valentinite and senarmontite. Like most polymeric oxides, Sb2O3 dissolves in aqueous solutions with hydrolysis. A mixed arsenic-antimony oxide occurs in nature as the very rare mineral stibioclaudetite. Production and properties Global production of antimony(III) oxide in 2012 was 130,000 tonnes, an increase from 112,600 tonnes in 2002. China produces the largest share followed by US/Mexico, Europe, Japan and South Africa and other countries (2%). As of 2010, antimony(III) oxide was produced at four sites in EU27. It is produced via two routes, re-volatilizing of crude antimony(III) oxide and by oxidation of antimony metal. Oxidation of antimony metal dominates in Europe. Several processes for the production of crude antimony(III) oxide or metallic antimony from virgin material. The choice of process depends on th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Antimony Trioxide Antimony(III) oxide is the inorganic compound with the formula Sb2O3. It is the most important commercial compound of antimony. It is found in nature as the minerals valentinite and senarmontite. Like most polymeric oxides, Sb2O3 dissolves in aqueous solutions with hydrolysis. A mixed arsenic-antimony oxide occurs in nature as the very rare mineral stibioclaudetite. Production and properties Global production of antimony(III) oxide in 2012 was 130,000 tonnes, an increase from 112,600 tonnes in 2002. China produces the largest share followed by US/Mexico, Europe, Japan and South Africa and other countries (2%). As of 2010, antimony(III) oxide was produced at four sites in EU27. It is produced via two routes, re-volatilizing of crude antimony(III) oxide and by oxidation of antimony metal. Oxidation of antimony metal dominates in Europe. Several processes for the production of crude antimony(III) oxide or metallic antimony from virgin material. The choice of process depends on th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Kermesite Kermesite or antimony oxysulfide is also known as red antimony (Sb2S2O) . The mineral's color ranges from cherry red to a dark red to a black. Kermesite is the result of partial oxidation between stibnite (Sb2S3) and other antimony oxides such as valentinite (Sb2O3) or stibiconite (Sb3O6(OH)). Under certain conditions with oxygenated fluids the transformation of all sulfur to oxygen would occur but kermesite occurs when that transformation is halted. Mining and specimens Deposits of this mineral have been found all over the world, however notable deposits have been found in Braunsdorf, near Freiberg, Saxony, Germany; Pernek, Pezinok, and Pribram, Czechoslovakia; the Lac Nicolet mine, South Ham Township, Wolfe County, Quebec, Canada; Sombrerete, Zacatecas, Mexico; Santa Cruz and San Francisco mines, Poopo, Oruro, Bolivia; Que Que, Zimbabwe; Djebel Haminate, Algeria; Broken Hill, New South Wales, Australia; Mohave, Kern County, California and Burke, Shoshone County, Idaho. Hist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Cervantite Cervantite is an antimony oxide mineral with formula Sb3+Sb5+O4 ( antimony tetroxide). It was first described in 1850 for an occurrence in Cervantes, Sierra de Ancares, Lugo, Galicia, Spain, and named for the locality. The mineral was questioned and disapproved, but re-approved and verified in 1962 based on material from the Zajaca-Stolice district, Brasina, Serbia. It occurs as a secondary alteration product of antimony bearing minerals, mainly stibnite Stibnite, sometimes called antimonite, is a sulfide mineral with the formula Sb2 S3. This soft grey material crystallizes in an orthorhombic space group. It is the most important source for the metalloid antimony. The name is derived from the .... References Oxide minerals Antimony minerals Orthorhombic minerals Minerals in space group 33 {{Oxide-mineral-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Stibiconite Stibiconite is an antimony oxide mineral with formula: Sb3O6(OH). Its name originates from Greek "stibi" (antimony) and "konis" (powder), alluding to its composition and habit. It is a member of the pyrochlore super group. Discovery and occurrence It was first described in 1862 for an occurrence in the Brandholz - Goldkronach District, Fichtelgebirge, Franconia, Bavaria. It occurs as a secondary alteration product of other hydrothermal antimony minerals such as stibnite. It occurs in association with cervantite, valentinite, kermesite Kermesite or antimony oxysulfide is also known as red antimony (Sb2S2O) . The mineral's color ranges from cherry red to a dark red to a black. Kermesite is the result of partial oxidation between stibnite (Sb2S3) and other antimony oxides such a ..., native antimony and stibnite. References Antimony minerals Oxide minerals Cubic minerals Minerals in space group 227 {{oxide-mineral-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	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]
picture info	Oxidation Redox (reduction–oxidation, , ) is a type of chemical reaction in which the oxidation states of substrate change. Oxidation is the loss of 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 hydrogenation, C=C (and other) bonds ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Hydrothermal Hydrothermal circulation in its most general sense is the circulation of hot water (Ancient Greek ὕδωρ, ''water'',Liddell, H.G. & Scott, R. (1940). ''A Greek-English Lexicon. revised and augmented throughout by Sir Henry Stuart Jones. with the assistance of. Roderick McKenzie.'' Oxford: Clarendon Press. and θέρμη, ''heat'' ). Hydrothermal circulation occurs most often in the vicinity of sources of heat within the Earth's crust. In general, this occurs near volcanic activity, but can occur in the shallow to mid crust along deeply penetrating fault irregularities or in the deep crust related to the intrusion of granite, or as the result of orogeny or metamorphism. Seafloor hydrothermal circulation Hydrothermal circulation in the oceans is the passage of the water through mid-oceanic ridge systems. The term includes both the circulation of the well-known, high-temperature vent waters near the ridge crests, and the much-lower-temperature, diffuse flow of water through sedim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	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 often showing octahedral forms. It is often associated with the minerals sphalerite, calcite and fluorite. Occurrence Galena is the main ore of lead, used since ancient times, since lead can be smelted from galena in an ordinary wood fire. Galena typically is found in hydrothermal veins in association with sphalerite, marcasite, chalcopyrite, cerussite, anglesite, dolomite, calcite, quartz, barite, and fluorite. It is also found in association with sphalerite in low-temperature lead-zinc deposits within limestone beds. Minor amounts are found in contact metamorphic zones, in pegmatites, and disseminated in sedimentary rock. In some deposits the galena contains up to 0.5% silver, a byproduct that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]