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Aluminite Outcrop At Newhaven Cliffs
Aluminite is a hydrous aluminium sulfate mineral with formula: Al2SO4(OH)4·7H2O. It is an earthy white to gray-white monoclinic mineral which almost never exhibits crystal form. It forms botryoidal to mammillary clay-like masses. It has a very soft Mohs hardness of 1–2 and a specific gravity of 1.66–1.82. It forms in clay and lignite deposits as an oxidation product of pyrite and marcasite along with aluminium silicates. It also occurs in volcanic sublimates, in native sulfur deposits and rarely in caves. It occurs in association with basaluminite, gibbsite, epsomite, gypsum, celestine, dolomite and goethite. It was first described in 1807 from Halle, Saxony-Anhalt, Germany and named for its aluminium content. It is also known as ''alley stone'', ''halite'' and ''websterite'' (named after Orcadian Orcadians, also known as Orkneymen, are an ethnic group native to the Orkney Islands, who speak an Orcadian dialect of the Scots language, a West Germanic language, and sha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Igneous Rock
Igneous rock (derived from the Latin word ''ignis'' meaning fire), or magmatic rock, is one of the three main The three types of rocks, rock types, the others being Sedimentary rock, sedimentary and metamorphic rock, metamorphic. Igneous rock is formed through the cooling and solidification of magma or lava. The magma can be derived from Partial melting, partial melts of existing rocks in either a Terrestrial planet, planet's mantle (geology), mantle or crust (geology), crust. Typically, the melting is caused by one or more of three processes: an increase in temperature, a decrease in pressure, or a change in composition. Solidification into rock occurs either below the surface as intrusive rocks or on the surface as extrusive (geology), extrusive rocks. Igneous rock may form with crystallization to form granular, crystalline rocks, or without crystallization to form Volcanic glass, natural glasses. Igneous rocks occur in a wide range of geological settings: shields, platforms ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cave
A cave or cavern is a natural void in the ground, specifically a space large enough for a human to enter. Caves often form by the weathering of rock and often extend deep underground. The word ''cave'' can refer to smaller openings such as sea caves, rock shelters, and grottos, that extend a relatively short distance into the rock and they are called ''exogene'' caves. Caves which extend further underground than the opening is wide are called ''endogene'' caves. Speleology is the science of exploration and study of all aspects of caves and the cave environment. Visiting or exploring caves for recreation may be called ''caving'', ''potholing'', or ''spelunking''. Formation types The formation and development of caves is known as ''speleogenesis''; it can occur over the course of millions of years. Caves can range widely in size, and are formed by various geological processes. These may involve a combination of chemical processes, erosion by water, tectonic forces, microorgani ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aluminium Minerals
Aluminium (aluminum in American and Canadian English) is a chemical element with the symbol Al and atomic number 13. Aluminium has a density lower than those of other common metals, at approximately one third that of steel. It has a great affinity towards oxygen, and forms a protective layer of oxide on the surface when exposed to air. Aluminium visually resembles silver, both in its color and in its great ability to reflect light. It is soft, non-magnetic and ductile. It has one stable isotope, 27Al; this isotope is very common, making aluminium the twelfth most common element in the Universe. The radioactivity of 26Al is used in radiodating. Chemically, aluminium is a post-transition metal in the boron group; as is common for the group, aluminium forms compounds primarily in the +3 oxidation state. The aluminium cation Al3+ is small and highly charged; as such, it is polarizing, and bonds aluminium forms tend towards covalency. The strong affinity towards oxyg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thomas Webster (geologist)
Thomas Webster (11 February 177226 December 1844) was a Scottish geologist. Life Webster was born in Orkney in 1772, probably at Kirkwall, and was educated at Aberdeen. He subsequently went to London and studied architecture, the Royal Institution in Albemarle Street being built from his design, and where in 1830 he delivered the Royal Institution Christmas Lecture. In 1826 he was appointed house-secretary and curator to the Geological Society of London, and for many years he rendered important services in editing and illustrating the ''Transactions'' of the Society. In 1841–42 he was professor of geology in University College, London. He was an accomplished water-colour painter and was elected an honorary member of the Sketch Society. He contributed articles about Architecture and Aquatinta to ''Rees's Cyclopædia''. ''An Encyclopaedia of Domestic Economy'', a comprehensive guide to running a household which Webster had compiled with the help of a Mrs. Parkes, was published ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orcadian
Orcadians, also known as Orkneymen, are an ethnic group native to the Orkney Islands, who speak an Orcadian dialect of the Scots language, a West Germanic language, and share a common history, culture and ancestry. Speaking Norn, a native North Germanic language into the 19th or 20th century,Jones, Charles (1997). ''The Edinburgh History of the Scots Language''. Edinburgh University Press. p. 394. Orcadians descend significantly from North Germanic peoples, with around a third of their ancestry derived from Scandinavia, including a majority of their patrilineal line. According to anthropological study, the Orcadian ethnic composition is similar to that of Icelandic people; a comparable islander ethnicity of North Germanic extraction. Historically, they are also descended from the Picts, Norse, and Lowland Scots. Background Orcadian ethnic group formation An Orcadian ethnicity has developed since around 900 AD. Goethe University's historian, Daniel Föller, describes the Orcadia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Germany
Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated between the Baltic and North seas to the north, and the Alps to the south; it covers an area of , with a population of almost 84 million within its 16 constituent states. Germany borders Denmark to the north, Poland and the Czech Republic to the east, Austria and Switzerland to the south, and France, Luxembourg, Belgium, and the Netherlands to the west. The nation's capital and most populous city is Berlin and its financial centre is Frankfurt; the largest urban area is the Ruhr. Various Germanic tribes have inhabited the northern parts of modern Germany since classical antiquity. A region named Germania was documented before AD 100. In 962, the Kingdom of Germany formed the bulk of the Holy Roman Empire. During the 16th ce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saxony-Anhalt
Saxony-Anhalt (german: Sachsen-Anhalt ; nds, Sassen-Anholt) is a state of Germany, bordering the states of Brandenburg, Saxony, Thuringia and Lower Saxony. It covers an area of and has a population of 2.18 million inhabitants, making it the 8th-largest state in Germany by area and the 11th-largest by population. Its capital is Magdeburg and its largest city is Halle (Saale). The state of Saxony-Anhalt was formed in July 1945 after World War II, when the Soviet army administration in Allied-occupied Germany formed it from the former Prussian Province of Saxony and the Free State of Anhalt. Saxony-Anhalt became part of the German Democratic Republic in 1949, but was dissolved in 1952 during administrative reforms and its territory divided into the districts of Halle and Magdeburg. Following German reunification the state of Saxony-Anhalt was re-established in 1990 and became one of the new states of the Federal Republic of Germany. Saxony-Anhalt is renowned for its ri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Halle, Saxony-Anhalt
Halle (Saale), or simply Halle (; from the 15th to the 17th century: ''Hall in Sachsen''; until the beginning of the 20th century: ''Halle an der Saale'' ; from 1965 to 1995: ''Halle/Saale'') is the largest city of the German state of Saxony-Anhalt, the fifth most populous city in the area of former East Germany after (East) Berlin, Leipzig, Dresden and Chemnitz, as well as the 31st largest city of Germany, and with around 239,000 inhabitants, it is slightly more populous than the state capital of Magdeburg. Together with Leipzig, the largest city of Saxony, Halle forms the polycentric Leipzig-Halle conurbation. Between the two cities, in Schkeuditz, lies Leipzig/Halle International Airport. The Leipzig-Halle conurbation is at the heart of the larger Central German Metropolitan Region. Halle lies in the south of Saxony-Anhalt, in the Leipzig Bay, the southernmost part of the North German Plain, on the River Saale (a tributary of the Elbe), which is the third longest river flo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Goethite
Goethite (, ) is a mineral of the diaspore group, consisting of iron(III) oxide-hydroxide, specifically the "α" polymorph. It is found in soil and other low-temperature environments such as sediment. Goethite has been well known since ancient times for its use as a pigment (brown ochre). Evidence has been found of its use in paint pigment samples taken from the caves of Lascaux in France. It was first described in 1806 based on samples found in the Hollertszug Mine in Herdorf, Germany. The mineral was named after the German polymath and poet Johann Wolfgang von Goethe (1749–1832). Composition Goethite is an iron oxyhydroxide containing ferric iron. It is the main component of rust and bog iron ore. Goethite's hardness ranges from 5.0 to 5.5 on the Mohs Scale, and its specific gravity varies from 3.3 to 4.3. The mineral forms prismatic needle-like crystals ("needle ironstone") but is more typically massive. Feroxyhyte and lepidocrocite are both polymorphs of the iron oxy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dolomite (mineral)
Dolomite () is an anhydrous carbonate mineral composed of calcium magnesium carbonate, ideally The term is also used for a sedimentary carbonate rock composed mostly of the mineral dolomite. An alternative name sometimes used for the dolomitic rock type is dolostone. History As stated by Nicolas-Théodore de Saussure the mineral dolomite was probably first described by Carl Linnaeus in 1768. In 1791, it was described as a rock by the French naturalist and geologist Déodat Gratet de Dolomieu (1750–1801), first in buildings of the old city of Rome, and later as samples collected in the mountains now known as the Dolomite Alps of northern Italy. Nicolas-Théodore de Saussure first named the mineral (after Dolomieu) in March 1792. Properties The mineral dolomite crystallizes in the trigonal-rhombohedral system. It forms white, tan, gray, or pink crystals. Dolomite is a double carbonate, having an alternating structural arrangement of calcium and magnesium ions. Unless it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Celestine (mineral)
Celestine (the IMA-accepted name) or celestite is a mineral consisting of strontium sulfate ( Sr S O). The mineral is named for its occasional delicate blue color. Celestine and the carbonate mineral strontianite are the principal sources of the element strontium, commonly used in fireworks and in various metal alloys. Etymology Celestine derives its name from the Latin word ''caelestis'' meaning celestial which in turn is derived from the Latin word ''caelum'' meaning sky or heaven. Occurrence Celestine occurs as crystals, and also in compact massive and fibrous forms. It is mostly found in sedimentary rocks, often associated with the minerals gypsum, anhydrite, and halite. On occasion in some localities, it may also be found with sulfur inclusions. The mineral is found worldwide, usually in small quantities. Pale blue crystal specimens are found in Madagascar. White and orange variants also occurred at Yate, Bristol, UK, where it was extracted for commercial purposes unt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gypsum
Gypsum is a soft sulfate mineral composed of calcium sulfate dihydrate, with the chemical formula . It is widely mined and is used as a fertilizer and as the main constituent in many forms of plaster, blackboard or sidewalk chalk, and drywall. Alabaster, a fine-grained white or lightly tinted variety of gypsum, has been used for sculpture by many cultures including Ancient Egypt, Mesopotamia, Ancient Rome, the Byzantine Empire, and the Nottingham alabasters of Medieval England. Gypsum also crystallizes as translucent crystals of selenite. It forms as an evaporite mineral and as a hydration product of anhydrite. The Mohs scale of mineral hardness defines gypsum as hardness value 2 based on scratch hardness comparison. Etymology and history The word ''gypsum'' is derived from the Greek word (), "plaster". Because the quarries of the Montmartre district of Paris have long furnished burnt gypsum (calcined gypsum) used for various purposes, this dehydrated gypsum became known ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
