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Pyrophyllite
Pyrophyllite is a phyllosilicate mineral composed of aluminium silicate hydroxide: Al2Si4O10(OH)2. It occurs in two forms (habits): crystalline folia and compact masses; distinct crystals are not known. The folia have a pronounced pearly luster, owing to the presence of a perfect cleavage parallel to their surfaces: they are flexible but not elastic, and are usually arranged radially in fan-like or spherical groups. This variety, when heated , exfoliates and swells up to many times its original volume, hence the name pyrophyllite, from the Greek ''pyro-'' (πυρο-, the combining form of πῦρ fire) and ''phyllos'' (a leaf), given by R. Hermann in 1829. The color of both varieties is white, pale green, greyish or yellowish; they are very soft (hardness of 1.0 to 1.5) and are greasy to the touch. The specific gravity is 2.65 - 2.85. The two varieties are thus very similar to talc. Occurrence Pyrophyllite occurs in phyllite and schistose rocks, often associated with kyanite, o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mineral
In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid chemical compound 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 geological definition of mineral normally excludes compounds that occur only in living organisms. However, some minerals are often biogenic (such as calcite) or are 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, 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 of two or more different types of minerals, spacially segregated into distinct ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kyanite
Kyanite is a typically blue aluminosilicate mineral, found in aluminium-rich metamorphic pegmatites and sedimentary rock. It is the high pressure polymorph of andalusite and sillimanite, and the presence of kyanite in metamorphic rocks generally indicates metamorphism deep in the Earth's crust. Kyanite is also known as disthene or cyanite. Kyanite is strongly anisotropic, in that its hardness varies depending on its crystallographic direction. In kyanite, this anisotropism can be considered an identifying characteristic, along with its characteristic blue color. Its name comes from the same origin as that of the color cyan, being derived from the Ancient Greek word κύανος. This is generally rendered into English as ''kyanos'' or ''kuanos'' and means "dark blue". Kyanite is used as a raw material in the manufacture of ceramics and abrasives, and it is an important index mineral used by geologists to trace metamorphic zones. Properties Kyanite is an aluminum silicate mine ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Talc
Talc, or talcum, is a Clay minerals, clay mineral, composed of hydrated magnesium silicate with the chemical formula Mg3Si4O10(OH)2. Talc in powdered form, often combined with corn starch, is used as baby powder. This mineral is used as a thickening agent and lubricant. It is an ingredient in ceramics, paints, and roofing material. It is a main ingredient in many cosmetics. It occurs as Foliation (geology), foliated to Fiber, fibrous masses, and in an exceptionally rare crystal form. It has a perfect cleavage (crystal), basal cleavage and an uneven flat fracture, and it is foliated with a two-dimensional ped, platy form. The Mohs scale of mineral hardness, based on Scratch hardness, scratch hardness comparison, defines value 1 as the hardness of talc, the softest mineral. When scraped on a streak (mineralogy), streak plate, talc produces a white streak; though this indicator is of little importance, because most silicate minerals produce a white streak. Talc is translucent to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crystal Habit
In mineralogy, crystal habit is the characteristic external shape of an individual crystal or crystal group. The habit of a crystal is dependent on its crystallographic form and growth conditions, which generally creates irregularities due to limited space in the crystallizing medium (commonly in rocks).Klein, Cornelis, 2007, ''Minerals and Rocks: Exercises in Crystal and Mineral Chemistry, Crystallography, X-ray Powder Diffraction, Mineral and Rock Identification, and Ore Mineralogy,'' Wiley, third edition, Wenk, Hans-Rudolph and Andrei Bulakh, 2004, ''Minerals: Their Constitution and Origin,'' Cambridge, first edition, Recognizing the habit can aid in mineral identification and description, as the crystal habit is an external representation of the internal ordered atomic arrangement. Most natural crystals, however, do not display ideal habits and are commonly malformed. Hence, it is also important to describe the quality of the shape of a mineral specimen: * Euhedral: a cr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beresovsk
Beryozovskoye deposit, Berezovskoe gold deposit, Berezovsky deposit, Berezovsk Mines, and some other names (russian: Берёзовское месторождение) is the first known primary deposit of gold in Russia. It is located 13 km northwest of Yekaterinburg in the central Urals Federal District. It was discovered in 1745 by a ''raskolnik'' Yerofey Markov. Minerals of the Beryozovskoye gold ore deposit The first mine was established in 1747. The deposit is named after the Beryozovka River (a tributary of ) and is associated with the settle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silicate Minerals
Silicate minerals are rock-forming minerals made up of silicate groups. They are the largest and most important class of minerals and make up approximately 90 percent of Earth's crust. In mineralogy, silica (silicon dioxide, ) is usually considered a silicate mineral. Silica is found in nature as the mineral quartz, and its polymorphs. On Earth, a wide variety of silicate minerals occur in an even wider range of combinations as a result of the processes that have been forming and re-working the crust for billions of years. These processes include partial melting, crystallization, fractionation, metamorphism, weathering, and diagenesis. Living organisms also contribute to this geologic cycle. For example, a type of plankton known as diatoms construct their exoskeletons ("frustules") from silica extracted from seawater. The frustules of dead diatoms are a major constituent of deep ocean sediment, and of diatomaceous earth. General structure A silicate mineral is general ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yekaterinburg
Yekaterinburg ( ; rus, Екатеринбург, p=jɪkətʲɪrʲɪnˈburk), alternatively romanized as Ekaterinburg and formerly known as Sverdlovsk ( rus, Свердло́вск, , svʲɪrˈdlofsk, 1924–1991), is a city and the administrative centre of Sverdlovsk Oblast and the Ural Federal District, Russia. The city is located on the Iset River between the Volga-Ural region and Siberia, with a population of roughly 1.5 million residents, up to 2.2 million residents in the urban agglomeration. Yekaterinburg is the fourth-largest city in Russia, the largest city in the Ural Federal District, and one of Russia's main cultural and industrial centres. Yekaterinburg has been dubbed the "Third capital of Russia", as it is ranked third by the size of its economy, culture, transportation and tourism. Yekaterinburg was founded on 18 November 1723 and named after the Russian emperor Peter the Great's wife, who after his death became Catherine I, Yekaterina being the Russian form o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manuels, Newfoundland And Labrador
Conception Bay South is a town located on the southern shore of Conception Bay on the Avalon Peninsula of the island of Newfoundland, Province of Newfoundland and Labrador, Canada. The town is commonly called C.B.S. Conception Bay South is the second largest settlement in Newfoundland and Labrador and is part of the St. John's Metropolitan Area. Geography The town is located on the southern shore of Conception Bay on the Avalon Peninsula of the island of Newfoundland. It is approximately 20 kilometres (12 miles) southwest of the provincial capital of St. John's. As such, the town is part of the St. John's Metropolitan Area and most residents are employed in the nearby cities of St. John's or Mount Pearl. The town lies on a zone of Cambrian bedrock, primarily shale containing limestone concretions and manganese ores. History Conception Bay South was formed in 1973 through the amalgamation of nine communities (Topsail, Chamberlains, Manuels, Long Pond, Foxtrap, Kelligrews, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Newfoundland And Labrador
Newfoundland and Labrador (; french: Terre-Neuve-et-Labrador; frequently abbreviated as NL) is the easternmost province of Canada, in the country's Atlantic region. The province comprises the island of Newfoundland and the continental region of Labrador, having a total size of 405,212 square kilometres (156,500 sq mi). In 2021, the population of Newfoundland and Labrador was estimated to be 521,758. The island of Newfoundland (and its smaller neighbouring islands) is home to around 94 per cent of the province's population, with more than half residing in the Avalon Peninsula. Labrador borders the province of Quebec, and the French overseas collectivity of Saint Pierre and Miquelon lies about 20 km west of the Burin Peninsula. According to the 2016 census, 97.0 per cent of residents reported English as their native language, making Newfoundland and Labrador Canada's most linguistically homogeneous province. A majority of the population is descended from English and Irish s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zermatt
Zermatt () is a municipality in the district of Visp in the German-speaking section of the canton of Valais in Switzerland. It has a year-round population of about 5,800 and is classified as a town by the Swiss Federal Statistical Office (FSO). It lies at the upper end of Mattertal at an elevation of , at the foot of Switzerland's highest peaks. It lies about from the over high Theodul Pass bordering Italy. Zermatt is the southernmost commune of the German ''Sprachraum''. Zermatt is famed as a mountaineering and ski resort of the Swiss Alps. Until the mid-19th century, it was predominantly an agricultural community; the first and tragic ascent of the Matterhorn in 1865 was followed by a rush on the mountains surrounding the village, leading to the construction of many tourist facilities. The year-round population () is , though there may be several times as many tourists in Zermatt at any one time. Much of the local economy is based on tourism, with about half of the jobs in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ural Mountains
The Ural Mountains ( ; rus, Ура́льские го́ры, r=Uralskiye gory, p=ʊˈralʲskʲɪjə ˈɡorɨ; ba, Урал тауҙары) or simply the Urals, are a mountain range that runs approximately from north to south through western Russia, from the coast of the Arctic Ocean to the river Ural and northwestern Kazakhstan.Ural Mountains Encyclopædia Britannica on-line The mountain range forms part of the conventional boundary between the regions of and |
Mica
Micas ( ) are a group of silicate minerals whose outstanding physical characteristic is that individual mica crystals can easily be split into extremely thin elastic plates. This characteristic is described as perfect basal cleavage. Mica is common in igneous and metamorphic rock and is occasionally found as small flakes in sedimentary rock. It is particularly prominent in many granites, pegmatites, and schists, and "books" (large individual crystals) of mica several feet across have been found in some pegmatites. Micas are used in products such as drywalls, paints, fillers, especially in parts for automobiles, roofing and shingles, as well as in electronics. The mineral is used in cosmetics and food to add "shimmer" or "frost." Properties and structure The mica group is composed of 37 phyllosilicate minerals. All crystallize in the monoclinic system, with a tendency towards pseudohexagonal crystals, and are similar in structure but vary in chemical composition. Micas are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
