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Wulfenite
Wulfenite is a lead molybdate mineral with the formula Pb Mo O4. It often occurs as thin tabular crystals with a bright orange-red to yellow-orange color, sometimes brown, although the color can be highly variable. In its yellow form it is sometimes called "yellow lead ore". It crystallizes in the tetragonal system, often occurring as stubby, pyramidal or tabular crystals. It also occurs as earthy, granular masses. It is found in many localities, associated with lead ores as a secondary mineral associated with the oxidized zone of lead deposits. It is also a secondary ore of molybdenum, and is sought by collectors. Discovery and occurrence Wulfenite was first described in 1845 for an occurrence in Bad Bleiberg, Carinthia, Austria. It was named for Franz Xaver von Wulfen (1728–1805), an Austrian mineralogist. It occurs as a secondary mineral in oxidized hydrothermal lead deposits. It occurs with cerussite, anglesite, smithsonite, hemimorphite, vanadinite, pyromorph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetragonal
In crystallography, the tetragonal crystal system is one of the 7 crystal systems. Tetragonal crystal lattices result from stretching a cubic lattice along one of its lattice vectors, so that the Cube (geometry), cube becomes a rectangular Prism (geometry), prism with a square base (''a'' by ''a'') and height (''c'', which is different from ''a''). Bravais lattices There are two tetragonal Bravais lattices: the primitive tetragonal and the body-centered tetragonal. The body-centered tetragonal lattice is equivalent to the primitive tetragonal lattice with a smaller unit cell, while the face-centered tetragonal lattice is equivalent to the body-centered tetragonal lattice with a smaller unit cell. Crystal classes The point groups that fall under this crystal system are listed below, followed by their representations in international notation, Schoenflies notation, orbifold notation, Coxeter notation and mineral examples.Hurlbut, Cornelius S.; Klein, Cornelis, 1985, ''Ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mineral
In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid substance with a fairly well-defined chemical composition and a specific crystal structure that occurs naturally in pure form.John P. Rafferty, ed. (2011): Minerals'; p. 1. In the series ''Geology: Landforms, Minerals, and Rocks''. Rosen Publishing Group. The Geology, geological definition of mineral normally excludes compounds that occur only in living organisms. However, some minerals are often biogenic (such as calcite) or organic compounds in the sense of chemistry (such as mellite). Moreover, living organisms often synthesize inorganic minerals (such as hydroxylapatite) that also occur in rocks. The concept of mineral is distinct from rock (geology), rock, which is any bulk solid geologic material that is relatively homogeneous at a large enough scale. A rock may consist of one type of mineral or may be an aggregate (geology), aggregate of two or more different types of minerals, spaci ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vanadinite
Vanadinite is a mineral belonging to the apatite group of Phosphate minerals, phosphates, with the chemical formula lead, Pb5(vanadium, Voxygen, O4)3chlorine, Cl. It is one of the main industrial ores of the metal vanadium and a minor source of lead. A dense, brittle mineral, it is usually found in the form of red hexagonal crystals. It is an uncommon mineral, formed by the oxidation of lead ore deposits such as galena. First discovered in 1801 in Mexico, vanadinite deposits have since been unearthed in South America, Europe, Africa, and North America. Origins Vanadinite is an uncommon mineral, only occurring as the result of chemical alterations to a pre-existing material. It is therefore known as a secondary mineral. It is found in arid climates and forms by Redox, oxidation of primary lead minerals. Vanadinite is especially found in association with the lead sulfide, galena. Other associated minerals include wulfenite, limonite, and barite. It was originally discovered in Me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molybdenum
Molybdenum is a chemical element; it has Symbol (chemistry), symbol Mo (from Neo-Latin ''molybdaenum'') and atomic number 42. The name derived from Ancient Greek ', meaning lead, since its ores were confused with lead ores. Molybdenum minerals have been known throughout history, but the element was discovered (in the sense of differentiating it as a new entity from the mineral salts of other metals) in 1778 by Carl Wilhelm Scheele. The metal was first isolated in 1781 by Peter Jacob Hjelm. Molybdenum does not occur naturally as a Native metal, free metal on Earth; in its minerals, it is found only in oxidation state, oxidized states. The free element, a silvery metal with a grey cast, has the List of elements by melting point, sixth-highest melting point of any element. It readily forms hard, stable carbides in alloys, and for this reason most of the world production of the element (about 80%) is used in steel alloys, including high-strength alloys and superalloys. Most molybdenum ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetragonal Crystal System
In crystallography, the tetragonal crystal system is one of the 7 crystal systems. Tetragonal crystal lattices result from stretching a cubic lattice along one of its lattice vectors, so that the cube becomes a rectangular prism with a square base (''a'' by ''a'') and height (''c'', which is different from ''a''). Bravais lattices There are two tetragonal Bravais lattices: the primitive tetragonal and the body-centered tetragonal. The body-centered tetragonal lattice is equivalent to the primitive tetragonal lattice with a smaller unit cell, while the face-centered tetragonal lattice is equivalent to the body-centered tetragonal lattice with a smaller unit cell. Crystal classes The point groups that fall under this crystal system are listed below, followed by their representations in international notation, Schoenflies notation, orbifold notation, Coxeter notation and mineral examples.Hurlbut, Cornelius S.; Klein, Cornelis, 1985, ''Manual of Mineralogy'', 20th ed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plattnerite
Plattnerite is an oxide mineral and is the beta crystalline form of lead dioxide (β-PbO2), scrutinyite being the other, alpha form. It was first reported in 1845 and named after German mineralogist Karl Friedrich Plattner. Plattnerite forms bundles of dark needle-like crystals on various minerals; the crystals are hard and brittle and have tetragonal symmetry. Occurrence Plattnerite is found in numerous arid locations in North America (US and Mexico), most of Europe, Asia (Iran and Russia), Africa (Namibia) and Southern and Western Australia. It occurs in weathered Hydrothermal circulation, hydrothermal base-metal deposits as hay-like bundles of dark prismatic crystals with a length of a few millimeters; the bundles grow on, or sometimes within various minerals, including cerussite, smithsonite, hemimorphite, leadhillite, hydrozincite, rosasite, aurichalcite, murdochite, limonite, pyromorphite, wulfenite, calcite and quartz. Properties and applications Basic properties of plat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Descloizite
Descloizite is a rare mineral species consisting of basic lead and zinc vanadium, vanadate, , crystallizing in the orthorhombic crystal system and isomorphous with olivenite. Appreciable gallium and germanium may also be incorporated into the crystal structure. The color is deep cherry-red to brown or black, and the crystals are transparent or translucent with a greasy lustre; the streak is orange-yellow to brown; specific gravity 5.9 to 6.2; hardness 31/2. A variety known as cuprodescloizite is dull green in color; it contains a considerable amount of copper replacing zinc and some arsenic replacing vanadium. There is also an arsenate analogue called arsendescloizite. Discovery and occurrence It was discovered in the Sierra de Córdoba deposit in Córdoba, Argentina, Córdoba, Argentina, in 1854 and named in honor of the French mineralogist Alfred Des Cloizeaux (1817–1897). It occurs as small prismatic or pyramidal crystals, usually forming Druse (geology), drusy crusts and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Franz Xaver Von Wulfen
Franz Xaver Freiherr von Wulfen (5 November 1728 – 17 March 1805) was an Austrian botanist, zoologist, mineralogist, alpinist, and Jesuit priest. He is credited with discovering the flowering plants '' Wulfenia carinthiaca'', '' Saxifraga moschata'', and '' Stellaria bulbosa''. In 1845 the lead molybdate mineral wulfenite was named in his honor by Wilhelm Karl von Haidinger. Life Wulfen was born in Belgrade. His father, Christian Friedrich von Wulfen, was a high-ranking lieutenant in the Austrian Army of Swedish descent. His mother, née Mariassy, was a Hungarian countess. Franz's education took place at Kaschau Gymnasium in present-day Košice, Slovakia. When he was 17, he joined a Jesuit school in Vienna. Following his graduation, he became a school instructor (chiefly of mathematics and physics) in Vienna, Graz, Neusohl, Gorz, Laibach (Ljubljana), and from 1764 Klagenfurt. After the Suppression of the Society of Jesus in the 1760s, he remained in Klagenfurt until ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peca (mountain)
Petzen (German) or Peca ( Slovene) is the highest mountain of the eastern Karawanks, the second-highest mountain of the Northern Karawanks and the most eastern two-thousand-metre mountain of Slovenia. It is a mighty mountain with a characteristic shape of a tableland with rocky peaks protruding from it. The mountain borders the Meža Valley and the Topla Valley to the south and east, and the Jaun Valley to the north, and is separated by the narrow valley of the Bela Creek from Hochobir. Two thirds of the mountain lies in Austria, and one third in Slovenia. The mountain reaches its highest elevation on the mountain crest of the Kordež Head (Slovene: , German: , ). The border runs across it. The mountain is built of Triassic Wetterstein limestone and Wetterstein dolomite. In the past, lead and zinc was mined on Peca, the shafts belonging to the Topla and Mežica mines. The lead-zinc ore occurs in Middle to Upper Triassic carbonate rocks deposited in an anoxic supratidal mar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mimetite
Mimetite is a lead arsenate chloride mineral () which forms as a secondary mineral in lead deposits, usually by the Redox, oxidation of galena and arsenopyrite. The name derives from the Greek ''mimetes'', meaning "imitator" and refers to mimetite's resemblance to the mineral pyromorphite. This resemblance is not coincidental, as mimetite forms a mineral series with pyromorphite () and with vanadinite (). Notable occurrences are Mapimi, Durango, Mexico, and Tsumeb, Namibia. Properties Mimetite typically forms short hexagonal crystals that are yellow to brown to orange in color, very brittle, moderately hard (Mohs hardness 3.5–4), and dense (specific gravity 7.24). It is distinctive for its lack of transparency, its resinous to adamantine Luster (mineralogy), luster, and its solubility in nitric acid. Mimetite forms a complete solid solution series with pyromorphite, with phosphate () substituting for arsenate (). The two minerals are almost identical in their properties and c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyromorphite
Pyromorphite is a mineral species composed of lead chlorophosphate: Pb5( P O4)3 Cl, sometimes occurring in sufficient abundance to be mined as an ore of lead. Crystals are common, and have the form of a hexagonal prism terminated by the basal planes, sometimes combined with narrow faces of a hexagonal pyramid. Crystals with a barrel-like curvature are not uncommon. Globular and reniform masses are also found. Pyromorphite is part of the apatite group of minerals and bears a close resemblance physically and chemically with two other minerals: mimetite (Pb5( AsO4)3Cl) and vanadinite (Pb5( VO4)3Cl). The resemblance in external characters is so close that, as a rule, it is only possible to distinguish between them by chemical tests. They were formerly confused under the names green lead ore and brown lead ore (''German: Grünbleierz and Braunbleierz''). History The mineral was first distinguished chemically by M. H. Klaproth in 1784, and it was named pyromorphite by J. F. L. H ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molybdate
In chemistry, a molybdate is a compound containing an oxyanion with molybdenum in its highest oxidation state of +6: . Molybdenum can form a very large range of such oxyanions, which can be discrete structures or polymeric extended structures, although the latter are only found in the solid state. The larger oxyanions are members of group of compounds termed ''polyoxometalates'', and because they contain only one type of metal atom are often called ''isopolymetalates''. The discrete molybdenum oxyanions range in size from the simplest , found in potassium molybdate up to extremely large structures found in isopoly-molybdenum blues that contain for example 154 Mo atoms. The behaviour of molybdenum is different from the other elements in group 6. Chromium only forms the chromates, , , and ions which are all based on tetrahedral chromium. Tungsten is similar to molybdenum and forms many tungstates containing 6 coordinate tungsten. Examples of molybdate anions Examples of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
