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Quartzolite
Quartzolite or silexite is an intrusive igneous rock, in which the mineral quartz is more than 90% of the rock's felsic mineral content, with feldspar at up to 10%. Typically, quartz forms more than 60% of the rock, the rest being mostly feldspar although minor amounts of mica or amphibole may also be present. Quartzolite occurs as dykes, sills, veins, bosses and segregation masses; it is also found in association with greisen and pegmatite. Quartzolite is an extremely rare type of rock. No extrusive rock equivalent of quartzolite is known. Synonyms The use of the synonym "''silexite"'' is discouraged because it is the French word for chert, which is a sedimentary rock. Other less common synonyms are "''igneous quartz''" and "''peracidite''". Examples * Chrastava, Czech Republic * Crag Mountain, Northfield, Massachusetts, United States * Jabal Hamra, Saudi Arabia * Keivy, Kola Peninsula, Russia * Lyon Mountain quadrangle, New York state, United States * Moulting Pond, Newf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quartz
Quartz is a hard, crystalline mineral composed of silica ( silicon dioxide). The atoms are linked in a continuous framework of SiO4 silicon-oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall chemical formula of SiO2. Quartz is the second most abundant mineral in Earth's continental crust, behind feldspar. Quartz exists in two forms, the normal α-quartz and the high-temperature β-quartz, both of which are chiral. The transformation from α-quartz to β-quartz takes place abruptly at . Since the transformation is accompanied by a significant change in volume, it can easily induce microfracturing of ceramics or rocks passing through this temperature threshold. There are many different varieties of quartz, several of which are classified as gemstones. Since antiquity, varieties of quartz have been the most commonly used minerals in the making of jewelry and hardstone carvings, especially in Eurasia. Quartz is the mineral defini ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Torrington, New South Wales
Torrington (formerly Torington) is a small village in northern New South Wales in Tenterfield Shire. It is 29 kilometres north west of Deepwater and south west of Tenterfield and 61 kilometres from Glen Innes (South-East). It is situated on a plateau known as the Mole Tableland in close proximity to the Queensland border on the Northern Tablelands. A feature of Torrington is its abundance of boulders and rocky outcrops. The most notable boulder outcrop located in the village being "Goat Rock" and just out of town is "Old Mystery Face" History Torrington was named after its English counterpart in Devon. The discovery of the extremely rich Torrington tin lode in 1881 created much excitement but in a very short time the small prospectors had lost control to overseas mining companies, the precursors of today's multi-nationals. In the 1920s, 500 men were employed at the mines. There were sixteen batteries working, and the community enjoyed the convenience of five ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chert
Chert () is a hard, fine-grained sedimentary rock composed of microcrystalline or cryptocrystalline quartz, the mineral form of silicon dioxide (SiO2). Chert is characteristically of biological origin, but may also occur inorganically as a chemical precipitate or a diagenetic replacement, as in petrified wood. Chert is typically composed of the petrified remains of siliceous ooze, the biogenic sediment that covers large areas of the deep ocean floor, and which contains the silicon skeletal remains of diatoms, silicoflagellates, and radiolarians. Precambrian cherts are notable for the presence of fossil cyanobacteria. In addition to microfossils, chert occasionally contains macrofossils. However, some chert is devoid of any fossils. Chert varies greatly in color (from white to black), but most often manifests as gray, brown, grayish brown and light green to rusty redW.L. Roberts, T.J. Campbell, G.R. Rapp Jr., "Encyclopedia of Mineralogy, Second Edition", 1990. R.S. Mitc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metamorphic Rock
Metamorphic rocks arise from the transformation of existing rock to new types of rock in a process called metamorphism. The original rock ( protolith) is subjected to temperatures greater than and, often, elevated pressure of or more, causing profound physical or chemical changes. During this process, the rock remains mostly in the solid state, but gradually recrystallizes to a new texture or mineral composition. The protolith may be an igneous, sedimentary, or existing metamorphic rock. Metamorphic rocks make up a large part of the Earth's crust and form 12% of the Earth's land surface. They are classified by their protolith, their chemical and mineral makeup, and their texture. They may be formed simply by being deeply buried beneath the Earth's surface, where they are subject to high temperatures and the great pressure of the rock layers above. They can also form from tectonic processes such as continental collisions, which cause horizontal pressure, friction, and dis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pluton
In geology, an igneous intrusion (or intrusive body or simply intrusion) is a body of intrusive igneous rock that forms by crystallization of magma slowly cooling below the surface of the Earth. Intrusions have a wide variety of forms and compositions, illustrated by examples like the Palisades Sill of New York and New Jersey; the Henry Mountains of Utah; the Bushveld Igneous Complex of South Africa; Shiprock in New Mexico; the Ardnamurchan intrusion in Scotland; and the Sierra Nevada Batholith of California. Because the solid country rock into which magma intrudes is an excellent insulator, cooling of the magma is extremely slow, and intrusive igneous rock is coarse-grained ( phaneritic). Intrusive igneous rocks are classified separately from extrusive igneous rocks, generally on the basis of their mineral content. The relative amounts of quartz, alkali feldspar, plagioclase, and feldspathoid is particularly important in classifying intrusive igneous rocks. Intrusi ... [...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 near ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Topaz
Topaz is a silicate mineral of aluminium and fluorine with the chemical formula Al Si O( F, OH). It is used as a gemstone in jewelry and other adornments. Common topaz in its natural state is colorless, though trace element impurities can make it pale blue or golden brown to yellow orange. Topaz is often treated with heat or radiation to make it a deep blue, reddish-orange, pale green, pink, or purple. Although it is often associated with golden yellow and blue, it comes in a variety of colors, including colorless. The rarest are natural pinks, reds, and delicate golden oranges, sometimes with pink hues. Topaz is a nesosilicate mineral. It is one of the hardest naturally occurring minerals and has a relatively low index of refraction. It occurs in many places in the world. Etymology The name "topaz" is usually believed to be derived (via Old French: Topace and Latin: Topazus) from the Greek ''Τοπάζιος'' (Topázios) or ''Τοπάζιον'' (Topázion), from Τοπα ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South Mountains (Arizona)
The South Mountains ( O'odham: ''Muhaḍagĭ Doʼag'', Yavapai: ''Wi:ki'tiyeda'', mrc, Vii Kwxas), known locally as simply South Mountain, is a mountain range in central Arizona in south Phoenix, Arizona. It is on public land managed by the city of Phoenix as South Mountain Park. Geologically, the South Mountains are thought to be a metamorphic core complex: evidence of movement of the North American tectonic plates from southwest to northeast and northeast to southwest, pushing up a series of mountain ranges including South Mountain. Other ridges with parallel orientation lie within the basin covered by basin fill sediments. The structural basin forms the current Phoenix metro area, which appears flat like a lake around mountains that rise over it like islands. The buried ridges are in the same orientation as the South Mountains, about one km high, and about one km apart from peak to peak, perhaps about 15 of them underneath the basin fill. The mountain, along with the nearb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South Georgia
South Georgia ( es, Isla San Pedro) is an island in the South Atlantic Ocean that is part of the British Overseas Territory of South Georgia and the South Sandwich Islands. It lies around east of the Falkland Islands. Stretching in the east–west direction, South Georgia is around long and has a maximum width of . The terrain is mountainous, with the central ridge rising to at Mount Paget. The northern coast is indented with numerous bays and fjords, serving as good harbours. Discovered by Europeans in 1675, South Georgia had no indigenous population due to its harsh climate and remoteness. Captain James Cook in made the first landing, survey and mapping of the island, and on 17 January 1775 he claimed it a British possession, naming it "Isle of Georgia" after King George III. Through its history, it served as a whaling and seal hunting base, with intermittent population scattered in several whaling bases, the most important historically being Grytviken. The main settlem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saveh County
Saveh County ( fa, شهرستان ساوه, ''Ŝahrestāne Sāweh'') is located in Markazi province, Iran. The capital of the county is Saveh Saveh ( fa, ساوه, translit=Sāveh, also transliterated as ''Sāwa'') is a city in Markazi Province of Iran. It is located about southwest of Tehran. As of 2011, the city had a population of 259,030 people. History In the 7th century BC it .... At the 2006 census, the county's population was 235,843, in 63,672 households. Retrieved 5 November 2022 At the 2011 census, the county's population was 259,030 people. At the 2016 census, the county's population was 283,538, in 87,444 households. Administrative divisions Gallery Masjed-jame-saveh.JPG, Jameh Mosque of Saveh Imamzadeh Seyed Haroun 1.jpg, Imamzadeh Seyed Haroun References Counties of Markazi Province {{Markazi-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lyon Mountain, New York
Lyon Mountain is a hamlet and census-designated place located in the town of Dannemora in Clinton County, New York, United States. The population was 423 at the 2010 census. The northern slopes of Lyon Mountain are in the southern part of the community, with the summit to the south in the town of Saranac. The Lyon Mountain Correctional Facility, a minimum security prison, was located in the community. The facility closed in 2011, and has been purchased by a Canadian who has mined sand for hydrofracking from the site. Geography The hamlet of Lyon Mountain is located at (44.728863, -73.907905). According to the United States Census Bureau, the CDP has a total area of , all land. Lyon Mountain is on New York State Route 374, which leads east to Dannemora village and northwest to Chateaugay. Demographics As of the census of 2000, there were 458 people, 214 households, and 129 families residing in the hamlet. The population density was 45.0 per square mile (17.4/km2). There ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
