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Sillimanite
Sillimanite or fibrolite is an aluminosilicate mineral with the chemical formula Al2SiO5. Sillimanite is named after the American chemist Benjamin Silliman (1779–1864). It was first described in 1824 for an occurrence in Chester, Connecticut. Occurrence Sillimanite or fibrolite is one of three aluminosilicate polymorphs, the other two being andalusite and kyanite. A common variety of sillimanite is known as ''fibrolite'', so named because the mineral appears like a bunch of fibres twisted together when viewed in thin section or even by the naked eye. Both the fibrous and traditional forms of sillimanite are common in metamorphosed sedimentary rocks. It is an index mineral indicating high temperature but variable pressure. Example rocks include gneiss and granulite. It occurs with andalusite, kyanite, potassium feldspar, almandine, cordierite, biotite and quartz in schist, gneiss, hornfels and also rarely in pegmatites. Dumortierite and mullite are similar mine ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benjamin Silliman
Benjamin Silliman (August 8, 1779 – November 24, 1864) was an American chemist and science education, science educator. He was one of the first American professors of science, the first science professor at Yale University, Yale, and the first person to use the process of fractional distillation in America. He was a founder of the ''American Journal of Science'', the oldest continuously published scientific journal in the United States. Early life Silliman was born in a tavern in North Stratford, now Trumbull, Connecticut, to Mary Silliman, Mary (Fish) Silliman (widow of John Noyes) and General Gold Selleck Silliman. He was born in August 1779, several months after British forces took his father prisoner and his mother had fled their home in Fairfield, Connecticut, to escape 2,000 British troops who burned Fairfield center to the ground. Silliman was educated at Yale, receiving a Bachelor of Arts, B.A. degree in 1796 and a Master of Arts, M.A. in 1799. He studied law with S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metamorphism
Metamorphism is the transformation of existing Rock (geology), rock (the protolith) to rock with a different mineral composition or Texture (geology), texture. Metamorphism takes place at temperatures in excess of , and often also at elevated pressure or in the presence of chemically active fluids, but the rock remains mostly solid during the transformation. Metamorphism is distinct from weathering or diagenesis, which are changes that take place at or just beneath Earth's surface. Various forms of metamorphism exist, including Regional metamorphism, regional, Contact metamorphism, contact, Hydrothermal metamorphism, hydrothermal, Shock metamorphism, shock, and Dynamic metamorphism, dynamic metamorphism. These differ in the characteristic temperatures, pressures, and rate at which they take place and in the extent to which reactive fluids are involved. Metamorphism occurring at increasing pressure and temperature conditions is known as ''prograde metamorphism'', while decreasin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nesosilicate
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, the crystalline forms of silica (silicon dioxide, ) are usually considered to be tectosilicates, and they are classified as such in the Dana system (75.1). However, the Nickel-Strunz system classifies them as oxide minerals (4.DA). 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 seaw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hornfels
Hornfels is the group name for a set of Metamorphism#Contact .28thermal.29, contact metamorphic rocks that have been baked and hardened by the heat of Intrusive rock, intrusive igneous masses and have been rendered massive, hard, splintery, and in some cases exceedingly tough and durable. These properties are caused by fine grained non-aligned crystals with platy or prismatic Crystal habit, habits, characteristic of metamorphism at high temperature but without accompanying deformation. The term is derived from the German word ''Hornfels'', meaning "hornstone", because of its exceptional toughness and texture both reminiscent of animal horns. These rocks were referred to by miners in northern England as Sharpening stone, whetstones. Most hornfels are fine-grained, and while the original rocks (such as sandstone, shale, slate and limestone) may have been more or less fissile owing to the presence of bedding or Cleavage (geology), cleavage planes, this structure is effaced or rendered ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Index Mineral
An index mineral is used in geology to determine the degree of metamorphism a rock has experienced. Depending on the original composition of and the pressure and temperature experienced by the protolith (parent rock), chemical reactions between minerals in the solid state produce new minerals. When an index mineral is found in a metamorphosed rock, it indicates the minimum pressure and temperature the protolith must have achieved in order for that mineral to form. The higher the pressure and temperature in which the rock formed, the higher the grade of the rock. The concept traces its roots to 1912, when G. M. Barrow mapped zones of metamorphism in Scotland. Each zone is named for the index mineral that appears in it, for example, the chlorite zone is named for chlorite. Mineralogic zones Mudrock, a fine-grained sedimentary rock often containing aluminium-rich minerals, produces these minerals after being metamorphosed, from low to high grade:Blatt, Harvey and Robert J. Tracy, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Delaware Mineralogical Society
The Delaware Mineralogical Society, Inc., also known as DMS, is a U.S. registered tax-deductible 503(c)(3) non-profit organization located in Wilmington, Delaware, US. Its primary purpose is to promote education in the earth sciences. DMS was instrumental in the recommendation of Delaware's official mineral Sillimanite to the Delaware State Legislature in 1977. History The Delaware Mineralogical Society was founded in 1960. Its members have professional and hobbyist interests in geology, mineralogy, paleontology, and the lapidary arts. Some members are professional scientists and educators, such as chemists, geologists, school teachers, and college professors. Students also make up a portion of the society's membership. The club hosts educational programs, field trips, and an annual show the first full weekend in March. The monthly newsletter, ''The Geogram'', is published every month, except July and August. The group has also published over 60 articles about specific geologi ... [...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] |
Chemical Formula
A chemical formula is a way of presenting information about the chemical proportions of atoms that constitute a particular chemical compound or molecule, using chemical element symbols, numbers, and sometimes also other symbols, such as parentheses, dashes, brackets, commas and ''plus'' (+) and ''minus'' (−) signs. These are limited to a single typographic line of symbols, which may include subscripts and superscripts. A chemical formula is not a chemical name since it does not contain any words. Although a chemical formula may imply certain simple chemical structures, it is not the same as a full chemical structural formula. Chemical formulae can fully specify the structure of only the simplest of molecules and chemical substances, and are generally more limited in power than chemical names and structural formulae. The simplest types of chemical formulae are called '' empirical formulae'', which use letters and numbers indicating the numerical ''proportions'' of atoms ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
New Castle County, Delaware
New Castle County is the northernmost of the three List of counties in Delaware, counties of the U.S. state of Delaware (New Castle, Kent County, Delaware, Kent, and Sussex County, Delaware, Sussex). As of the 2020 United States census, 2020 census, the population was 570,719, making it the most populous county in Delaware, with nearly 60% of the state's population of 989,948. The county seat is Wilmington, Delaware, Wilmington, which is also the state's most populous city. New Castle County is included in the Philadelphia-Camden, New Jersey, Camden-Wilmington, Delaware, Wilmington, Delaware Valley, PA-NJ-DE-MD Metropolitan Statistical Area. The county is named after William Cavendish, 1st Duke of Newcastle (–1676). New Castle County has the highest population and population density of any Delaware county, and it is the smallest county in the state by area. It has more people than the other two counties, Kent County, Delaware, Kent and Sussex County, Delaware, Sussex, combined. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brandywine Springs
Brandywine Springs is a historic area near Newport, Delaware, along the Red Clay Creek. It is noted from early American history as a Revolutionary War encampment of General George Washington's army. In 1826, a large four-storey resort hotel was built in Brandywine Springs. "The resort became an attraction for many persons of distinction and elegance both in national life and in society," wrote one early 20th-century history of the Newark area. Visitors included John Quincy Adams, Henry Clay, and Daniel Webster. The hotel and its grounds were purchased in 1832 by Matthew Newkirk, a wealthy Philadelphia merchant who owned a vacation cottage nearby. Newkirk spent considerable sums to improve the hotel and grounds. But by 1850 the hotel was failing. It was soon leased to Captain Alden Partridge, who opened the National Scientific and Military Academy there. But the school building was destroyed by fire shortly after opening and the school closed. In the 1880s, it became known once ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Porcelain
Porcelain (), also called china, is a ceramic material made by heating Industrial mineral, raw materials, generally including kaolinite, in a kiln to temperatures between . The greater strength and translucence of porcelain, relative to other types of pottery, arise mainly from Vitrification#Ceramics, vitrification and the formation of the mineral mullite within the body at these high temperatures. End applications include tableware, ceramic art, decorative ware such as figurines, and products in technology and industry such as Insulator (electricity), electrical insulators and laboratory ware. The manufacturing process used for porcelain is similar to that used for earthenware and stoneware, the two other main types of pottery, although it can be more challenging to produce. It has usually been regarded as the most prestigious type of pottery due to its delicacy, strength, and high degree of whiteness. It is frequently both glazed and decorated. Though definitions vary, po ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mullite
Mullite or porcelainite is a rare silicate mineral formed during contact metamorphism of clay minerals. It can form two stoichiometric forms: 3 Al2 O32 SiO2 or 2Al2O3 SiO2. Unusually, mullite has no charge-balancing cations present. As a result, there are three different aluminium sites: two distorted tetrahedral and one octahedral. Mullite was first described in 1924 for an occurrence on the Isle of Mull, Scotland. It occurs as argillaceous inclusions in volcanic rocks in the Isle of Mull, inclusions in sillimanite within a tonalite at Val Sissone, Italy and with emerylike rocks in Argyllshire, Scotland. Porcellanite Mullite (porcelainite) can be found as a constituent mineral in a type of thermally-metamorphosed rock called porcellanite. Use in porcelain Mullite is present in the form of needles in porcelain. It is produced during various melting and firing processes, and is used as a refractory material,H. Schneider & S. Komarneni (2005) Mullite. Wiley, VCH, 5 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
