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Fregeneda–Almendra Pegmatitic Field
The Fregeneda–Almendra pegmatitic field is a geologic area in the Iberian Peninsula extending across the Portuguese district of Guarda and the Spanish province of Salamanca. Part of the , it is located in the western part of a narrow E–W metamorphic belt. It consists of a variety of granitic pegmatites, where some rocks are rich in lithium. The Li minerals include spodumene, petalite, lithian muscovite and montebrasite. A mining site for the extraction of lithium, tin, niobium and tantalium Tantalum is a chemical element with the symbol Ta and atomic number 73. Previously known as ''tantalium'', it is named after Tantalus, a villain in Greek mythology. Tantalum is a very hard, ductile, lustrous, blue-gray transition metal that is h ... is located in La Fregeneda area. Bibliography ;References ;Bibliography * * * * {{DEFAULTSORT:Fregeneda-Almendra pegmatitic field Geology of the Iberian Peninsula ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iberian Peninsula
The Iberian Peninsula (), ** * Aragonese and Occitan: ''Peninsula Iberica'' ** ** * french: Péninsule Ibérique * mwl, Península Eibérica * eu, Iberiar penintsula also known as Iberia, is a peninsula in southwestern Europe, defining the westernmost edge of Eurasia. It is principally divided between Spain and Portugal, comprising most of their territory, as well as a small area of Southern France, Andorra, and Gibraltar. With an area of approximately , and a population of roughly 53 million, it is the second largest European peninsula by area, after the Scandinavian Peninsula. Name Greek name The word ''Iberia'' is a noun adapted from the Latin word "Hiberia" originating in the Ancient Greek word Ἰβηρία ('), used by Greek geographers under the rule of the Roman Empire to refer to what is known today in English as the Iberian Peninsula. At that time, the name did not describe a single geographical entity or a distinct population; the same name was us ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Guarda District
The district of Guarda ( pt, Distrito de Guarda ) is located in the Centro Region of Portugal, except Vila Nova de Foz Côa, which is in the Norte Region. The district capital and most populous city is Guarda. Municipalities The district contains 14 municipalities: * Aguiar da Beira * Almeida * Celorico da Beira * Figueira de Castelo Rodrigo * Fornos de Algodres * Gouveia * Guarda * Manteigas * Mêda * Pinhel * Sabugal * Seia * Trancoso * Vila Nova de Foz Côa Cities The following seat of municipalities have city (cidade)status: Gouveia, Guarda, Meda, Pinhel, Sabugal, Trancoso. Subregions Included within the District of Guarda Beira Interior Norte, Serra da Estrela, Douro and Dão-Lafões. Geography The main mountain ranges are the Serra da Estrela and Serra da Marofa. The main rivers are the Mondego, Côa, and Douro. Main Monuments/Castles * Guarda Sé/ Cathedral of Guarda. *Castles:(Castelos de) Pinhel, Sabugal, Sortelha, Marialva, Celorico, Rodrigo, Al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Province Of Salamanca
Salamanca () is a province of western Spain, in the western part of the autonomous community of Castile and León (Castilla y León). It is bordered by the provinces of Zamora, Valladolid, Ávila, and Cáceres, and on the west by Portugal. It has an area of 12,349 km² and in 2018 had a population of 331,473 people. It is divided into 362 municipalities, 11 comarcas, 32 mancomunidades and five judicial districts. Of the 362 municipalities, more than half are villages with fewer than 300 people. History The Vettones occupied the areas of the current Spanish provinces of Salamanca and Ávila, as well as parts of Cáceres, Toledo and Zamora. They were a pre-Roman people of Celtic culture. Their numerous archaeological sites exist throughout the province, and several locality names have Vettone origin, some of which are quite important. This is the case of Salamanca (''Salmantica''), Ledesma (''Bletisama'') and Ciudad Rodrigo (''Augustobriga''). Vettone villages were often esta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Granite
Granite () is a coarse-grained (phaneritic) intrusive igneous rock composed mostly of quartz, alkali feldspar, and plagioclase. It forms from magma with a high content of silica and alkali metal oxides that slowly cools and solidifies underground. It is common in the continental crust of Earth, where it is found in igneous intrusions. These range in size from dikes only a few centimeters across to batholiths exposed over hundreds of square kilometers. Granite is typical of a larger family of ''granitic rocks'', or ''granitoids'', that are composed mostly of coarse-grained quartz and feldspars in varying proportions. These rocks are classified by the relative percentages of quartz, alkali feldspar, and plagioclase (the QAPF classification), with true granite representing granitic rocks rich in quartz and alkali feldspar. Most granitic rocks also contain mica or amphibole minerals, though a few (known as leucogranites) contain almost no dark minerals. Granite is nearly alway ... [...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] |
Lithium
Lithium (from el, λίθος, lithos, lit=stone) is a chemical element with the symbol Li and atomic number 3. It is a soft, silvery-white alkali metal. Under standard conditions, it is the least dense metal and the least dense solid element. Like all alkali metals, lithium is highly reactive and flammable, and must be stored in vacuum, inert atmosphere, or inert liquid such as purified kerosene or mineral oil. When cut, it exhibits a metallic luster, but moist air corrodes it quickly to a dull silvery gray, then black tarnish. It never occurs freely in nature, but only in (usually ionic) compounds, such as pegmatitic minerals, which were once the main source of lithium. Due to its solubility as an ion, it is present in ocean water and is commonly obtained from brines. Lithium metal is isolated electrolytically from a mixture of lithium chloride and potassium chloride. The nucleus of the lithium atom verges on instability, since the two stable lithium isotopes foun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spodumene
Spodumene is a pyroxene mineral consisting of lithium aluminium inosilicate, Li Al( Si O3)2, and is a source of lithium. It occurs as colorless to yellowish, purplish, or lilac kunzite (see below), yellowish-green or emerald-green hiddenite, prismatic crystals, often of great size. Single crystals of in size are reported from the Black Hills of South Dakota, United States. The naturally-occurring low-temperature form α-spodumene is in the monoclinic system , and the high-temperature β-spodumene crystallizes in the tetragonal system. α-spodumene converts to β-spodumene at temperatures above 900 °C. Crystals are typically heavily striated parallel to the principal axis. Crystal faces are often etched and pitted with triangular markings. Discovery and occurrence Spodumene was first described in 1800 for an occurrence in the type locality in Utö, Södermanland, Sweden. It was discovered by Brazilian naturalist Jose Bonifacio de Andrada e Silva. The name is derived fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Petalite
Petalite, also known as castorite, is a lithium aluminum phyllosilicate mineral Li Al Si4 O10, crystallizing in the monoclinic system. Petalite occurs as colorless, pink, grey, yellow, yellow grey, to white tabular crystals and columnar masses. It occurs in lithium-bearing pegmatites with spodumene, lepidolite, and tourmaline. Petalite is an important ore of lithium, and is converted to spodumene and quartz by heating to ~500 °C and under 3 kbar of pressure in the presence of a dense hydrous alkali borosilicate fluid with a minor carbonate component. Petalite (and secondary spodumen formed from it) is lower in iron than primary spodumene, making it a more useful source of lithium in, e.g., the production of glass. The colorless varieties are often used as gemstones. Discovery and occurrence Petalite was discovered in 1800, by Brazilian naturalist and statesman Jose Bonifacio de Andrada e Silva. Type locality: Utö Island, Haninge, Stockholm, Sweden. The name is der ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Montebrasite
Amblygonite () is a fluorophosphate mineral, , composed of lithium, sodium, aluminium, phosphate, fluoride and hydroxide. The mineral occurs in pegmatite deposits and is easily mistaken for albite and other feldspars. Its density, cleavage and flame test for lithium are diagnostic. Amblygonite forms a series with ''montebrasite'', the low fluorine endmember. Geologic occurrence is in granite pegmatites, high-temperature tin veins, and greisens. Amblygonite occurs with spodumene, apatite, lepidolite, tourmaline, and other lithium-bearing minerals in pegmatite veins. It contains about 10% lithium, and has been utilized as a source of lithium. The chief commercial sources have historically been the deposits of California and France. History The mineral was first discovered in Saxony by August Breithaupt in 1817, and named by him from the Greek ''amblus'', blunt, and ''gonia'', angle, because of the obtuse angle between the cleavages. Later it was found at Montebras, Creuse, Franc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Niobium
Niobium is a chemical element with chemical symbol Nb (formerly columbium, Cb) and atomic number 41. It is a light grey, crystalline, and ductile transition metal. Pure niobium has a Mohs hardness rating similar to pure titanium, and it has similar ductility to iron. Niobium oxidizes in Earth's atmosphere very slowly, hence its application in jewelry as a hypoallergenic alternative to nickel. Niobium is often found in the minerals pyrochlore and columbite, hence the former name "columbium". Its name comes from Greek mythology: Niobe, daughter of Tantalus, the namesake of tantalum. The name reflects the great similarity between the two elements in their physical and chemical properties, which makes them difficult to distinguish. English chemist Charles Hatchett reported a new element similar to tantalum in 1801 and named it columbium. In 1809, English chemist William Hyde Wollaston wrongly concluded that tantalum and columbium were identical. German chemist Heinrich Rose determin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tantalium
Tantalum is a chemical element with the symbol Ta and atomic number 73. Previously known as ''tantalium'', it is named after Tantalus, a villain in Greek mythology. Tantalum is a very hard, ductile, lustrous, blue-gray transition metal that is highly corrosion-resistant. It is part of the refractory metals group, which are widely used as components of strong high-melting-point alloys. It is a group 5 element, along with vanadium and niobium, and it always occurs in geologic sources together with the chemically similar niobium, mainly in the mineral groups tantalite, columbite and coltan. The chemical inertness and very high melting point of tantalum make it valuable for laboratory and industrial equipment such as reaction vessels and vacuum furnaces. It is used in tantalum capacitors for electronic equipment such as computers. Tantalum is considered a technology-critical element by the European Commission. History Tantalum was discovered in Sweden in 1802 by Anders Ekeberg, i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
La Fregeneda
La Fregeneda is a municipality of Spain located in the province of Salamanca, Castile and León. As of 2016 the municipality has a population of 337 inhabitants. See also * Fregeneda–Almendra pegmatitic field The Fregeneda–Almendra pegmatitic field is a geologic area in the Iberian Peninsula extending across the Portuguese district of Guarda and the Spanish province of Salamanca. Part of the , it is located in the western part of a narrow E–W metam ... References Municipalities in the Province of Salamanca {{Salamanca-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
