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35-672: Pennine may refer to: Pennine, a black-green variant of clinochlore Pennines , a mountain range in England Pennine Alps , a mountain range in the western Alps Pennine Way , a National Trail in England and Scotland Pennine FM , an Independent Local Radio station in Huddersfield, West Yorkshire Rolls-Royce Pennine , a British 46-litre air-cooled sleeve valve engine with 24 cylinders arranged in an X formation Topics referred to by

70-479: A hexagonal array in two dimensions. The fourth oxygen ion is not shared with another tetrahedron and all of the tetrahedra "point" in the same direction; i.e. all of the unshared oxygen ions are on the same side of the sheet. These unshared oxygen ions are called apical oxygen ions. In clays, the tetrahedral sheets are always bonded to octahedral sheets formed from small cations, such as aluminum or magnesium, and coordinated by six oxygen atoms. The unshared vertex from

105-400: A net negative charge and may be bonded together either by individual cations (such as potassium in illite or sodium or calcium in smectites) or by positively charged octahedral sheets (as in chlorites ). Clay minerals include the following groups: Mixed layer clay variations exist for most of the above groups. Ordering is described as a random or regular order and is further described by

140-449: A positively charged brucite layer. Chlorite is considered a clay mineral . It is a nonswelling clay mineral, since water is not adsorbed in the interlayer spaces, and it has a relatively low cation exchange capacity . Chlorite is a common mineral, found in metamorphic, igneous, and sedimentary rocks. It is an important rock-forming mineral in low- to medium-grade metamorphic rock formed by metamorphism of mafic or pelitic rock. It

175-420: A traditional technique establishing fundamental occurrences or petrologic relationships. Clay minerals are common weathering products (including weathering of feldspar ) and low-temperature hydrothermal alteration products. Clay minerals are very common in soils, in fine-grained sedimentary rocks such as shale , mudstone , and siltstone and in fine-grained metamorphic slate and phyllite . Given

210-540: A very common material, and is the oldest known ceramic . Prehistoric humans discovered the useful properties of clay and used it for making pottery . The chemistry of clay, including its capacity to retain nutrient cations such as potassium and ammonium , is important to soil fertility. Because the individual particles in clay are less than 4 micrometers (0.00016 in) in size, they cannot be characterized by ordinary optical or physical methods. The crystallographic structure of clay minerals became better understood in

245-608: Is a common mineral in clay , which has a vast number of uses. Chlorite schist has been used as roofing granules, the mineral granules adhered to asphalt composition shingles due to the green color. It was quarried near Ely, Minnesota, US, until superseded by synthetic materials. Clay mineral Clay minerals are hydrous aluminium phyllosilicates (e.g. kaolin , Al 2 Si 2 O 5 ( OH ) 4 ), sometimes with variable amounts of iron , magnesium , alkali metals , alkaline earths , and other cations found on or near some planetary surfaces . Clay minerals form in

280-425: Is also common in igneous rocks, usually as a secondary mineral, formed by alteration of mafic minerals such as biotite , hornblende , pyroxene , or garnet . The glassy rims of pillow basalt on the ocean floor is often altered to pure chlorite, in part by exchange of chemicals with seawater. The green color of many igneous rocks, slates , and schists is due to fine particles of chlorite disseminated throughout

315-609: Is different from Wikidata All article disambiguation pages All disambiguation pages Clinochlore Chlorite minerals show a wide variety of compositions, in which magnesium, iron, aluminium, and silicon substitute for each other in the crystal structure. A complete solid solution series exists between the two most common end members, magnesium-rich clinochlore and iron-rich chamosite . In addition, manganese, zinc, lithium, and calcium species are known. The great range in composition results in considerable variation in physical, optical, and X-ray properties. Similarly,

350-504: Is formed from a stack of layers interspaced with the interlayers. Clay minerals can be classified as 1:1 or 2:1. A 1:1 clay would consist of one tetrahedral sheet and one octahedral sheet, and examples would be kaolinite and serpentinite . A 2:1 clay consists of an octahedral sheet sandwiched between two tetrahedral sheets, and examples are talc , vermiculite , and montmorillonite . The layers in 1:1 clays are uncharged and are bonded by hydrogen bonds between layers, but 2:1 layers have

385-400: Is known as corrensite , R1 illite-smectite is rectorite . X-ray rf(001) is the spacing between layers in nanometers, as determined by X-ray crystallography. Glycol (mg/g) is the adsorption capacity for glycol, which occupies the interlayer sites when the clay is exposed to a vapor of ethylene glycol at 60 °C (140 °F) for eight hours. CEC is the cation exchange capacity of

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420-431: Is only one tetrahedral and one octahedral group in each layer the clay is known as a 1:1 clay. The alternative, known as a 2:1 clay, has two tetrahedral sheets with the unshared vertex of each sheet pointing towards each other and forming each side of the octahedral sheet. Bonding between the tetrahedral and octahedral sheets requires that the tetrahedral sheet becomes corrugated or twisted, causing ditrigonal distortion to

455-458: The TOT layers of chlorite contain some aluminium in place of silicon, which gives the layers an overall negative charge. These TOT layers are bound together by positively charged O layers, sometimes called brucite layers. Mica is also composed of aluminium-rich, negatively charged TOT layers, but these are bonded together by individual cations (such as potassium, sodium, or calcium ions) rather than

490-407: The polymerization of RNA in aqueous solution from nucleotide monomers, and the formation of membranes from lipids. In 1998, Hyman Hartman proposed that "the first organisms were self-replicating iron-rich clays which fixed carbon dioxide into oxalic acid and other dicarboxylic acids . This system of replicating clays and their metabolic phenotype then evolved into the sulfide rich region of

525-993: The 1930s with advancements in the x-ray diffraction (XRD) technique indispensable to deciphering their crystal lattice. Clay particles were found to be predominantly sheet silicate (phyllosilicate) minerals, now grouped together as clay minerals. Their structure is based on flat hexagonal sheets similar to those of the mica group of minerals. Standardization in terminology arose during this period as well, with special attention given to similar words that resulted in confusion, such as sheet and plane. Because clay minerals are usually (but not necessarily) ultrafine-grained, special analytical techniques are required for their identification and study. In addition to X-ray crystallography, these include electron diffraction methods, various spectroscopic methods such as Mössbauer spectroscopy , infrared spectroscopy , Raman spectroscopy , and SEM - EDS or automated mineralogy processes. These methods can be augmented by polarized light microscopy ,

560-440: The applications of clays include drug delivery, tissue engineering, and bioprinting. Clay minerals can be incorporated in lime-metakaolin mortars to improve mechanical properties. Electrochemical separation helps to obtain modified saponite-containing products with high smectite-group minerals concentrations, lower mineral particles size, more compact structure, and greater surface area. These characteristics open possibilities for

595-571: The average pH level of 7.1 is reached at 30% of the pulp added and an experimental site with perennial grasses proved the efficacy of the technique. Moreover, the reclamation of disturbed lands is an integral part of the social and environmental responsibility of the mining company and this scenario addresses the community necessities at both local and regional levels. The results of glycol adsorption, cation exchange capacity, X-ray diffraction, differential thermal analysis, and chemical tests all give data that may be used for quantitative estimations. After

630-482: The clay. K 2 O (%) is the percent content of potassium oxide in the clay. DTA describes the differential thermal analysis curve of the clay. The clay hypothesis for the origin of life was proposed by Graham Cairns-Smith in 1985. It postulates that complex organic molecules arose gradually on pre-existing, non-organic replication surfaces of silicate crystals in contact with an aqueous solution. The clay mineral montmorillonite has been shown to catalyze

665-433: The dwarf planet Ceres , asteroid 101955 Bennu , and comet Tempel 1 , as well as Jupiter's moon Europa . Like all phyllosilicates, clay minerals are characterised by two-dimensional sheets of corner-sharing SiO 4 tetrahedra or AlO 4 octahedra. The sheet units have the chemical composition (Al, Si) 3 O 4 . Each silica tetrahedron shares three of its vertex oxygen ions with other tetrahedra, forming

700-426: The element chlorine , also named from the same Greek root. Chlorite forms blue-green crystals resembling mica . However, while the plates are flexible, they are not elastic like mica, and are less easily pulled apart. Talc is much softer and feels soapy between the fingers. The typical general formula for chlorite is (Mg,Fe) 3 (Si,Al) 4 O 10 (OH) 2 ·(Mg,Fe) 3 (OH) 6 . This formula emphasizes

735-454: The hexagonal array, and the octahedral sheet is flattened. This minimizes the overall bond-valence distortions of the crystallite. Depending on the composition of the tetrahedral and octahedral sheets, the layer will have no charge or will have a net negative charge. If the layers are charged this charge is balanced by interlayer cations such as Na or K or by a lone octahedral sheet. The interlayer may also contain water. The crystal structure

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770-425: The hot spring acquiring the ability to fix nitrogen . Finally phosphate was incorporated into the evolving system which allowed the synthesis of nucleotides and phospholipids." The structural and compositional versatility of clay minerals gives them interesting biological properties. Due to disc-shaped and charged surfaces, clay interacts with a range of drugs, protein, polymers, DNA, or other macromolecules. Some of

805-731: The mantle volume from which island arc magmas are generated. Clinochlore, pennantite, and chamosite are the most common varieties. Several other sub-varieties have been described. A massive compact variety of clinochlore used as a decorative carving stone is referred to by the trade name seraphinite . It occurs in the Korshunovskoye iron skarn deposit in the Irkutsk Oblast of Eastern Siberia . Chlorite does not have any specific industrial uses of any importance. Some rock types containing chlorite, such as chlorite schist, have minor decorative uses or as construction stone. However, chlorite

840-452: The manufacture of high-quality ceramics and heavy-metal sorbents from saponite-containing products. Furthermore, tail grinding occurs during the preparation of the raw material for ceramics; this waste reprocessing is of high importance for the use of clay pulp as a neutralizing agent, as fine particles are required for the reaction. Experiments on the histosol deacidification with the alkaline clay slurry demonstrated that neutralization with

875-400: The presence of water and have been important to life, and many theories of abiogenesis involve them. They are important constituents of soils , and have been useful to humans since ancient times in agriculture and manufacturing . Clay is a very fine-grained geologic material that develops plasticity when wet, but becomes hard, brittle and non–plastic upon drying or firing . It is

910-452: The quantities of organic matter, carbonates, free oxides, and nonclay minerals have been determined, the percentages of clay minerals are estimated using the appropriate glycol adsorption, cation exchange capacity, K20, and DTA data. The amount of illite is estimated from the K20 content since this is the only clay mineral containing potassium. Argillaceous rocks are those in which clay minerals are

945-498: The range of chemical composition allows chlorite group minerals to exist over a wide range of temperature and pressure conditions. For this reason chlorite minerals are ubiquitous minerals within low and medium temperature metamorphic rocks, some igneous rocks, hydrothermal rocks and deeply buried sediments. The name chlorite is from the Greek chloros (χλωρός), meaning "green", in reference to its color. Chlorite minerals do not contain

980-512: The remaining chlorite, often with release of water vapor. Chlorite is one of the most common minerals produced by propylitic alteration by hydrothermal systems , where it occurs in the "green rock" environment with epidote, actinolite, albite, hematite , and calcite . Experiments indicate that chlorite can be stable in peridotite of the Earth's mantle above the ocean lithosphere carried down by subduction , and chlorite may even be present in

1015-581: The requirement of water, clay minerals are relatively rare in the Solar System , though they occur extensively on Earth where water has interacted with other minerals and organic matter . Clay minerals have been detected at several locations on Mars , including Echus Chasma , Mawrth Vallis , the Memnonia quadrangle and the Elysium quadrangle . Spectrography has confirmed their presence on celestial bodies including

1050-468: The rock. Chlorite is a common weathering product and is widespread in clay and in sedimentary rock containing clay minerals. Chlorite is found in pelites along with quartz , albite , sericite , and garnet , and is also found in associate with actinolite and epidote . In his pioneering work on metamorphic facies in the Scottish Highlands, G.M. Barrow identified the chlorite zone as

1085-411: The same term [REDACTED] This disambiguation page lists articles associated with the title Pennine . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=Pennine&oldid=1214677957 " Category : Disambiguation pages Hidden categories: Short description

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1120-406: The structure of the group, which is described as TOT-O and consists of alternating TOT layers and O layers. The TOT layer ( T etrahedral- O ctahedral- T etrahedral = T-O-T ) is often referred to as a talc layer, since talc is composed entirely of stacked TOT layers. The TOT layers of talc are electrically neutral and are bound only by relatively weak van der Waals forces . By contrast,

1155-437: The term reichweite , which is German for range or reach. Literature articles will refer to an R1 ordered illite-smectite, for example. This type would be ordered in an illite-smectite-illite-smectite (ISIS) fashion. R0 on the other hand describes random ordering, and other advanced ordering types are also found (R3, etc.). Mixed layer clay minerals which are perfect R1 types often get their own names. R1 ordered chlorite-smectite

1190-402: The tetrahedral sheet also forms part of one side of the octahedral sheet, but an additional oxygen atom is located above the gap in the tetrahedral sheet at the center of the six tetrahedra. This oxygen atom is bonded to a hydrogen atom forming an OH group in the clay structure. Clays can be categorized depending on the way that tetrahedral and octahedral sheets are packaged into layers . If there

1225-455: The zone of mildest metamorphism. In modern petrology, chlorite is the diagnostic mineral of the greenschist facies. This facies is characterized by temperatures near 450 °C (840 °F) and pressures near 5 kbar. At higher temperatures, much of the chlorite is destroyed by reactions with either potassium feldspar or phengite mica which produce biotite , muscovite , and quartz . At still higher temperatures, other reactions destroy

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