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Psilomelane
Psilomelane is a group name for hard black manganese oxides including hollandite and romanechite. Psilomelane consists of hydrous manganese oxide with variable amounts of barium and potassium. Psilomelane is erroneously, and uncommonly, known as black hematite, despite not being related to true hematite, which is an iron oxide. Formula Generalized formula may be represented as or as . It is sometimes considered to be a hydrous manganese manganate, but of doubtful composition. The amount of manganese present corresponds to 70-80% of manganous oxide with 10-15% of available oxygen. Characteristics Psilomelane has no definite chemical composition and occurs as botryoidal and stalactitic masses with a smooth shining surface and submetallic lustre. The mineral is readily distinguished from other hydrous manganese oxides (manganite and wad) by its greater hardness 5 to 6; the specific gravity varies from 3.7 to 4.7. The streak is brownish black and the fracture smooth. The m ... [...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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyrolusite
Pyrolusite is a mineral consisting essentially of manganese dioxide ( Mn O2) and is important as an ore of manganese.. It is a black, amorphous appearing mineral, often with a granular, fibrous, or columnar structure, sometimes forming reniform crusts. It has a metallic luster, a black or bluish-black streak, and readily soils the fingers. The specific gravity is about 4.8. Its name is from the Greek for ''fire'' and to ''wash'', in reference to its use as a way to remove tints from glass. Occurrence Pyrolusite and romanechite are among the most common manganese minerals. Pyrolusite occurs associated with manganite, hollandite, hausmannite, braunite, chalcophanite, goethite, and hematite under oxidizing conditions in hydrothermal deposits. It also occurs in bogs and often results from alteration of manganite. Use The metal is obtained by reduction of the oxide with sodium, magnesium, aluminium, or by electrolysis. Pyrolusite is extensively used for the manufacture ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manganese Oxide
Manganese oxide is any of a variety of manganese oxides and hydroxides.Wells A.F. (1984) ''Structural inorganic chemistry'' 5th edition Oxford Science Publications, . These include * Manganese(II) oxide, MnO * Manganese(II,III) oxide, Mn3O4 * Manganese(III) oxide, Mn2O3 * Manganese dioxide, MnO2 * Manganese(VI) oxide, MnO3 * Manganese(VII) oxide, Mn2O7 Other manganese oxides include Mn5O8, Mn7O12 and Mn7O13. Minerals It may refer more specifically to the following manganese minerals: * Birnessite * Buserite * Hausmannite * Manganite * Manganosite * Psilomelane * Pyrolusite Manganese may also form mixed oxides with other metals : * Bixbyite, a manganese iron oxide mineral * Jacobsite, a manganese iron oxide mineral * Columbite * Tantalite, a mineral group close to columbite * Coltan, a mixture of columbite and tantalite * Galaxite, a spinel mineral * Todorokite Todorokite is a rare complex hydrous manganese oxide mineral with the chemical formula . It was named ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manganese
Manganese is a chemical element with the Symbol (chemistry), symbol Mn and atomic number 25. It is a hard, brittle, silvery metal, often found in minerals in combination with iron. Manganese is a transition metal with a multifaceted array of industrial alloy uses, particularly in stainless steels. It improves strength, workability, and resistance to wear. Manganese oxide is used as an oxidising agent; as a rubber additive; and in glass making, fertilisers, and ceramics. Manganese sulfate can be used as a fungicide. Manganese is also an essential human dietary element, important in macronutrient metabolism, bone formation, and free radical defense systems. It is a critical component in dozens of proteins and enzymes. It is found mostly in the bones, but also the liver, kidneys, and brain. In the human brain, the manganese is bound to manganese metalloproteins, most notably glutamine synthetase in astrocytes. Manganese was first isolated in 1774. It is familiar in the laborator ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hausmannite
Hausmannite is a complex oxide of manganese containing both di- and tri-valent manganese. The formula can be represented as Mn2+Mn3+2O4. It belongs to the spinel group and forms tetragonal crystals. Hausmannite is a brown to black metallic mineral with Mohs hardness of 5.5 and a specific gravity of 4.8. The type locality is Oehrenstock (Öhrenstock), Ilmenau, Thuringian Forest, Thuringia, Germany, where it was first described in 1813. Locations include Batesville, Arkansas, US; Ilfeld, Germany; Langban, Sweden; and the Ural Mountains, Russia. High quality samples have been found in South Africa and Namibia where it is associated with other manganese oxides, pyrolusite and psilomelane and the iron-manganese mineral bixbyite. Wilhelm Haidinger (1827) named it in honour of Johann Friedrich Ludwig Hausmann (1782–1859), Professor of Mineralogy, University of Göttingen, Germany. Image gallery File:Hausmannite-131901.jpg, Hausmannite from Wessels Mine, Kalahari manganese fields ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nova Scotia
Nova Scotia ( ; ; ) is one of the thirteen provinces and territories of Canada. It is one of the three Maritime provinces and one of the four Atlantic provinces. Nova Scotia is Latin for "New Scotland". Most of the population are native English-speakers, and the province's population is 969,383 according to the 2021 Census. It is the most populous of Canada's Atlantic provinces. It is the country's second-most densely populated province and second-smallest province by area, both after Prince Edward Island. Its area of includes Cape Breton Island and 3,800 other coastal islands. The Nova Scotia peninsula is connected to the rest of North America by the Isthmus of Chignecto, on which the province's land border with New Brunswick is located. The province borders the Bay of Fundy and Gulf of Maine to the west and the Atlantic Ocean to the south and east, and is separated from Prince Edward Island and the island of Newfoundland by the Northumberland and Cabot straits, resp ... [...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� ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Virginia
Virginia, officially the Commonwealth of Virginia, is a state in the Mid-Atlantic and Southeastern regions of the United States, between the Atlantic Coast and the Appalachian Mountains. The geography and climate of the Commonwealth are shaped by the Blue Ridge Mountains and the Chesapeake Bay, which provide habitat for much of its flora and fauna. The capital of the Commonwealth is Richmond; Virginia Beach is the most-populous city, and Fairfax County is the most-populous political subdivision. The Commonwealth's population was over 8.65million, with 36% of them living in the Baltimore–Washington metropolitan area. The area's history begins with several indigenous groups, including the Powhatan. In 1607, the London Company established the Colony of Virginia as the first permanent English colony in the New World. Virginia's state nickname, the Old Dominion, is a reference to this status. Slave labor and land acquired from displaced native tribes fueled the gro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vermont
Vermont () is a U.S. state, state in the northeast New England region of the United States. Vermont is bordered by the states of Massachusetts to the south, New Hampshire to the east, and New York (state), New York to the west, and the Provinces and territories of Canada, Canadian province of Quebec to the north. admission to the Union, Admitted to the union in 1791 as the 14th state, it is the only state in New England not bordered by the Atlantic Ocean. According to the 2020 United States census, 2020 U.S. census, the state has a population of 643,503, ranking it the List of U.S. states and territories by population, second least-populated in the U.S. after Wyoming. It is also the nation's List of U.S. states and territories by area, sixth-smallest state in area. List of capitals in the United States, The state's capital Montpelier, Vermont, Montpelier is the least-populous state capital in the U.S., while its most-populous city, Burlington, Vermont, Burlington, is the least- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cape Town
Cape Town ( af, Kaapstad; , xh, iKapa) is one of South Africa's three capital cities, serving as the seat of the Parliament of South Africa. It is the legislative capital of the country, the oldest city in the country, and the second largest (after Johannesburg). Colloquially named the ''Mother City'', it is the largest city of the Western Cape province, and is managed by the City of Cape Town metropolitan municipality. The other two capitals are Pretoria, the executive capital, located in Gauteng, where the Presidency is based, and Bloemfontein, the judicial capital in the Free State, where the Supreme Court of Appeal is located. Cape Town is ranked as a Beta world city by the Globalization and World Cities Research Network. The city is known for its harbour, for its natural setting in the Cape Floristic Region, and for landmarks such as Table Mountain and Cape Point. Cape Town is home to 66% of the Western Cape's population. In 2014, Cape Town was named the best pl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coblenz
Koblenz (; Moselle Franconian: ''Kowelenz''), spelled Coblenz before 1926, is a German city on the banks of the Rhine and the Moselle, a multi-nation tributary. Koblenz was established as a Roman military post by Drusus around 8 B.C. Its name originates from the Latin ', meaning "(at the) confluence". The actual confluence is today known as the " German Corner", a symbol of the unification of Germany that features an equestrian statue of Emperor William I. The city celebrated its 2000th anniversary in 1992. It ranks in population behind Mainz and Ludwigshafen am Rhein to be the third-largest city in Rhineland-Palatinate. Its usual-residents' population is 112,000 (as at 2015). Koblenz lies in a narrow flood plain between high hill ranges, some reaching mountainous height, and is served by an express rail and autobahn network. It is part of the populous Rhineland. History Ancient era Around 1000 BC, early fortifications were erected on the Festung Ehrenbreitstein ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orkney
Orkney (; sco, Orkney; on, Orkneyjar; nrn, Orknøjar), also known as the Orkney Islands, is an archipelago in the Northern Isles of Scotland, situated off the north coast of the island of Great Britain. Orkney is 10 miles (16 km) north of the coast of Caithness and has about 70 islands, of which 20 are inhabited. The largest island, the Mainland, has an area of , making it the sixth-largest Scottish island and the tenth-largest island in the British Isles. Orkney’s largest settlement, and also its administrative centre, is Kirkwall. Orkney is one of the 32 council areas of Scotland, as well as a constituency of the Scottish Parliament, a lieutenancy area, and an historic county. The local council is Orkney Islands Council, one of only three councils in Scotland with a majority of elected members who are independents. The islands have been inhabited for at least years, originally occupied by Mesolithic and Neolithic tribes and then by the Picts. Orkney was co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
