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46-732: It consists of shale, sandstone and conglomerate and is part of the Genesee Group . This article about a specific stratigraphic formation in New York state is a stub . You can help Misplaced Pages by expanding it . Genesee Group The Genesee Formation (Group) is a geologic formation in New York. It is equivalent the Harrell Shale in Pennsylvania. It date back to the Upper Devonian period . It

92-435: A Fe face-centered cubic sublattice into which the S 2 ions are embedded. (Note though that the iron atoms in the faces are not equivalent by translation alone to the iron atoms at the corners.) The pyrite structure is also seen in other MX 2 compounds of transition metals M and chalcogens X = O , S , Se and Te . Certain dipnictides with X standing for P , As and Sb etc. are also known to adopt

138-458: A form of tinder made of stringybark by the Kaurna people of South Australia , as a traditional method of starting fires. Pyrite has been used since classical times to manufacture copperas ( ferrous sulfate ). Iron pyrite was heaped up and allowed to weather (an example of an early form of heap leaching ). The acidic runoff from the heap was then boiled with iron to produce iron sulfate. In

184-602: A foul odor and corrosion of copper wiring. In the United States, in Canada, and more recently in Ireland, where it was used as underfloor infill, pyrite contamination has caused major structural damage. Concrete exposed to sulfate ions, or sulfuric acid, degrades by sulfate attack : the formation of expansive mineral phases, such as ettringite (small needle crystals exerting a huge crystallization pressure inside

230-617: A large number up to 70% shells from Styliolina fissurella. The color tends to be darker, grey black to brownish black. The Renwick was originally designated as a member of the Middlesex Formation by Caster (1933, p. 202). Later de Witt and Colton, 1959 were able to demonstrate that it was not part of the Sonyea and Middlesex, but in the Genesee. The name Sherburne was first coined by Vanuxem (1840, p. 381). The unit

276-409: A replacement mineral in fossils , but has also been identified in the sclerites of scaly-foot gastropods . Despite being nicknamed "fool's gold", pyrite is sometimes found in association with small quantities of gold. A substantial proportion of the gold is "invisible gold" incorporated into the pyrite (see Carlin-type gold deposit ). It has been suggested that the presence of both gold and arsenic

322-584: A simple liquid-phase exfoliation route. This is the first study to demonstrate the production of non-layered 2D-platelets from 3D bulk FeS 2 . Furthermore, they have used these 2D-platelets with 20% single walled carbon-nanotube as an anode material in lithium-ion batteries, reaching a capacity of 1000 mAh/g close to the theoretical capacity of FeS 2 . In 2021, a natural pyrite stone has been crushed and pre-treated followed by liquid-phase exfoliation into two-dimensional nanosheets, which has shown capacities of 1200 mAh/g as an anode in lithium-ion batteries. From

368-465: A superficial resemblance to gold , hence the well-known nickname of fool's gold . The color has also led to the nicknames brass , brazzle , and brazil , primarily used to refer to pyrite found in coal . The name pyrite is derived from the Greek πυρίτης λίθος ( pyritēs lithos ), 'stone or mineral which strikes fire', in turn from πῦρ ( pŷr ), 'fire'. In ancient Roman times, this name

414-465: Is cubic and was among the first crystal structures solved by X-ray diffraction . It belongs to the crystallographic space group Pa 3 and is denoted by the Strukturbericht notation C2. Under thermodynamic standard conditions the lattice constant a {\displaystyle a} of stoichiometric iron pyrite FeS 2 amounts to 541.87 pm . The unit cell is composed of

460-528: Is a 12' - 15' limestone bed found at the base of the West River Shale. Originally defined by Clarke (1903), this unit was reevaluated by de Witt and Colton, 1959 and defined at just the singular bed. Other limestone noted previously was found to be micro-concretions with in the Penn Yan. The Genundewa's lithology is made up of calcareous shale and mud supported limestones. Some beds are made up of

506-399: Is a case of coupled substitution but as of 1997 the chemical state of the gold remained controversial. Pyrite gained a brief popularity in the 16th and 17th centuries as a source of ignition in early firearms , most notably the wheellock , where a sample of pyrite was placed against a circular file to strike the sparks needed to fire the gun. Pyrite is used with flintstone and

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552-404: Is a common accessory mineral in igneous rocks, where it also occasionally occurs as larger masses arising from an immiscible sulfide phase in the original magma. It is found in metamorphic rocks as a product of contact metamorphism . It also forms as a high-temperature hydrothermal mineral , though it occasionally forms at lower temperatures. Pyrite occurs both as a primary mineral, present in

598-465: Is about 1 atm . A newer commercial use for pyrite is as the cathode material in Energizer brand non-rechargeable lithium metal batteries . Pyrite is a semiconductor material with a band gap of 0.95 eV . Pure pyrite is naturally n-type, in both crystal and thin-film forms, potentially due to sulfur vacancies in the pyrite crystal structure acting as n-dopants. During the early years of

644-458: Is accelerated by the action of Acidithiobacillus bacteria which oxidize pyrite to first produce ferrous ions ( Fe ), sulfate ions ( SO 4 ), and release protons (   H , or H 3 O ). In a second step, the ferrous ions ( Fe ) are oxidized by O 2 into ferric ions ( Fe ) which hydrolyze also releasing   H ions and producing FeO(OH). These oxidation reactions occur more rapidly when pyrite

690-423: Is accounted for by point symmetry groups C 3 i and C 3 , respectively. The missing center of inversion at S lattice sites has important consequences for the crystallographic and physical properties of iron pyrite. These consequences derive from the crystal electric field active at the sulfur lattice site, which causes a polarization of S ions in the pyrite lattice. The polarisation can be calculated on

736-554: Is also the fastest growing in terms of the unroasted iron pyrites imports, with a CAGR of +27.8% from 2007 to 2016. In July 2020 scientists reported that they have observed a voltage-induced transformation of normally diamagnetic pyrite into a ferromagnetic material, which may lead to applications in devices such as solar cells or magnetic data storage. Researchers at Trinity College Dublin , Ireland have demonstrated that FeS 2 can be exfoliated into few-layers just like other two-dimensional layered materials such as graphene by

782-526: Is brighter yellow with a greenish hue when wet and is softer (3.5–4 on Mohs' scale). Arsenopyrite (FeAsS) is silver white and does not become more yellow when wet. Iron pyrite is unstable when exposed to the oxidizing conditions prevailing at the Earth's surface: iron pyrite in contact with atmospheric oxygen and water, or damp, ultimately decomposes into iron oxyhydroxides ( ferrihydrite , FeO(OH)) and sulfuric acid ( H 2 SO 4 ). This process

828-443: Is brittle, gold is malleable. Natural gold tends to be anhedral (irregularly shaped without well defined faces), whereas pyrite comes as either cubes or multifaceted crystals with well developed and sharp faces easy to recognise. Well crystallised pyrite crystals are euhedral ( i.e. , with nice faces). Pyrite can often be distinguished by the striations which, in many cases, can be seen on its surface. Chalcopyrite ( CuFeS 2 )

874-449: Is finely dispersed (framboidal crystals initially formed by sulfate reducing bacteria (SRB) in argillaceous sediments or dust from mining operations). Pyrite oxidation by atmospheric O 2 in the presence of moisture ( H 2 O ) initially produces ferrous ions ( Fe ) and sulfuric acid which dissociates into sulfate ions and protons , leading to acid mine drainage (AMD). An example of acid rock drainage caused by pyrite

920-458: Is not a formally recognised mineral, and is named after the Peruvian scientist Jose J. Bravo (1874–1928). Pyrite is distinguishable from native gold by its hardness, brittleness and crystal form. Pyrite fractures are very uneven , sometimes conchoidal because it does not cleave along a preferential plane. Native gold nuggets , or glitters, do not break but deform in a ductile way. Pyrite

966-430: Is sprayed onto the exposed coal surfaces to reduce the hazard of dust explosions . This has the secondary benefit of neutralizing the acid released by pyrite oxidation and therefore slowing the oxidation cycle described above, thus reducing the likelihood of spontaneous combustion. In the long term, however, oxidation continues, and the hydrated sulfates formed may exert crystallization pressure that can expand cracks in

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1012-419: Is the 2015 Gold King Mine waste water spill . Pyrite oxidation is sufficiently exothermic that underground coal mines in high-sulfur coal seams have occasionally had serious problems with spontaneous combustion . The solution is the use of buffer blasting and the use of various sealing or cladding agents to hermetically seal the mined-out areas to exclude oxygen. In modern coal mines, limestone dust

1058-847: Is the basal unit of the Frasnian and Upper Devonian period. The Genesee Formation was defined by de Witt and Colton, 1959 as all strata between the Middlesex Unit of the Sonyea Group and the Tully Formation , where present or the Moscow Formation where the Tully is not present. The Genesee includes several members. Moving westward towards the Findley and Cincinnati Archs the formation thins to less than 9 feet. To

1104-532: Is unexposed to the elements is massive and shows some laminations. When weathered it becomes fissile. Pyrite and Calcite are found either in nodules or as fill in natural fractures. Due to its organic nature it is a source rock for Hydrocarbons , mostly Natural gas . Due to the anoxic environment necessary for the development of black shales, fossils are rare. The upper beds of the Geneseo do contain some scattered fossils of thin shelled organisms. Predominantly

1150-571: Is used to make marcasite jewelry . Marcasite jewelry, using small faceted pieces of pyrite, often set in silver , has been made since ancient times and was popular in the Victorian era . At the time when the term became common in jewelry making, "marcasite" referred to all iron sulfides including pyrite, and not to the orthorhombic FeS 2 mineral marcasite which is lighter in color, brittle and chemically unstable, and thus not suitable for jewelry making. Marcasite jewelry does not actually contain

1196-401: The brachiopod Orbiculoidea lodiensis. Loyalsburg Formation Pyrite The mineral pyrite ( / ˈ p aɪ r aɪ t / PY -ryte ), or iron pyrite , also known as fool's gold , is an iron sulfide with the chemical formula Fe S 2 (iron (II) disulfide). Pyrite is the most abundant sulfide mineral . Pyrite's metallic luster and pale brass-yellow hue give it

1242-522: The 15th century, new methods of such leaching began to replace the burning of sulfur as a source of sulfuric acid . By the 19th century, it had become the dominant method. Pyrite remains in commercial use for the production of sulfur dioxide , for use in such applications as the paper industry , and in the manufacture of sulfuric acid. Thermal decomposition of pyrite into FeS ( iron(II) sulfide ) and elemental sulfur starts at 540 °C (1,004 °F); at around 700 °C (1,292 °F), p S 2

1288-432: The 20th century, pyrite was used as a mineral detector in radio receivers, and is still used by crystal radio hobbyists. Until the vacuum tube matured, the crystal detector was the most sensitive and dependable detector available—with considerable variation between mineral types and even individual samples within a particular type of mineral. Pyrite detectors occupied a midway point between galena detectors and

1334-411: The Genesee formation. The West River is one of the most expansive members of the Genesee making it as far south as West Virginia. The West River is composed chiefly of shale and mudrocks. The color is usually medium to dark gray. As with most members the grain size increases moving eastward, making the formation silty in the east. Thin beds may be grey black and contain some iron staining. The Genundewa

1380-594: The Genudewan Limestone member and the Moscow Formation. Later the Geneseo was restricted to the lower two brownish black shale beds. Kirchgasser (1975, p. 62) and L. V. Rickard (oral communication., 1974) proposed that only the lower of the two brownish black beds was the Geneseo and the upper bed belongs to the Penn Yan. The Geneseo tends to be blackish in color. It may also have a brownish, olive, or grayish tint to it as well. Formation that

1426-452: The arrangement of the metal and diatomic anions differ from that of pyrite. Despite its name, chalcopyrite ( CuFeS 2 ) does not contain dianion pairs, but single S sulfide anions. Pyrite usually forms cuboid crystals, sometimes forming in close association to form raspberry-shaped masses called framboids . However, under certain circumstances, it can form anastomosing filaments or T-shaped crystals. Pyrite can also form shapes almost

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1472-426: The basis of higher-order Madelung constants and has to be included in the calculation of the lattice energy by using a generalised Born–Haber cycle . This reflects the fact that the covalent bond in the sulfur pair is inadequately accounted for by a strictly ionic treatment. Arsenopyrite has a related structure with heteroatomic As–S pairs rather than S-S pairs. Marcasite also possesses homoatomic anion pairs, but

1518-438: The concrete pores) and gypsum creates inner tensile forces in the concrete matrix which destroy the hardened cement paste, form cracks and fissures in concrete, and can lead to the ultimate ruin of the structure. Normalized tests for construction aggregate certify such materials as free of pyrite or marcasite. Pyrite is the most common of sulfide minerals and is widespread in igneous, metamorphic, and sedimentary rocks. It

1564-487: The east it feathers in with courser grained formations. The Genesee has several members. With courser clastic material coming mostly from the east there are several members that are feathered to the West River and Penn Yann on the eastern flanks. Below are listed the units found within the Genesee. Clarke and Luther (1904, p. 28) coined the name for the West River. Later, de Witt and Colton, 1959, assigned it to

1610-420: The mineral marcasite. The specimens of pyrite, when it appears as good quality crystals, are used in decoration. They are also very popular in mineral collecting. Among the sites that provide the best specimens are Soria and La Rioja provinces (Spain). In value terms, China ($ 47 million) constitutes the largest market for imported unroasted iron pyrites worldwide, making up 65% of global imports. China

1656-450: The more mechanically complicated perikon mineral pairs. Pyrite detectors can be as sensitive as a modern 1N34A germanium diode detector. Pyrite has been proposed as an abundant, non-toxic, inexpensive material in low-cost photovoltaic solar panels. Synthetic iron sulfide was used with copper sulfide to create the photovoltaic material. More recent efforts are working toward thin-film solar cells made entirely of pyrite. Pyrite

1702-715: The original sediments, and as a secondary mineral, deposited during diagenesis . Pyrite and marcasite commonly occur as replacement pseudomorphs after fossils in black shale and other sedimentary rocks formed under reducing environmental conditions. Pyrite is common as an accessory mineral in shale, where it is formed by precipitation from anoxic seawater, and coal beds often contain significant pyrite. Notable deposits are found as lenticular masses in Virginia, U.S., and in smaller quantities in many other locations. Large deposits are mined at Rio Tinto in Spain and elsewhere in

1748-444: The oxidation state of molybdenum is Mo . The mineral arsenopyrite has the formula Fe As S. Whereas pyrite has [S 2 ] units, arsenopyrite has [AsS] units, formally derived from deprotonation of arsenothiol (H 2 AsSH). Analysis of classical oxidation states would recommend the description of arsenopyrite as Fe [AsS] . Iron-pyrite FeS 2 represents the prototype compound of the crystallographic pyrite structure. The structure

1794-528: The perspective of classical inorganic chemistry , which assigns formal oxidation states to each atom, pyrite and marcasite are probably best described as Fe [S 2 ] . This formalism recognizes that the sulfur atoms in pyrite occur in pairs with clear S–S bonds. These persulfide [ S–S ] units can be viewed as derived from hydrogen disulfide , H 2 S 2 . Thus pyrite would be more descriptively called iron persulfide, not iron disulfide. In contrast, molybdenite , Mo S 2 , features isolated sulfide S centers and

1840-685: The pyrite structure. The Fe atoms are bonded to six S atoms, giving a distorted octahedron. The material is a semiconductor . The Fe ions is usually considered to be low spin divalent state (as shown by Mössbauer spectroscopy as well as XPS). The material as a whole behaves as a Van Vleck paramagnet , despite its low-spin divalency. The sulfur centers occur in pairs, described as S 2 . Reduction of pyrite with potassium gives potassium dithioferrate , KFeS 2 . This material features ferric ions and isolated sulfide (S ) centers. The S atoms are tetrahedral, being bonded to three Fe centers and one other S atom. The site symmetry at Fe and S positions

1886-643: The rock and lead eventually to roof fall . Building stone containing pyrite tends to stain brown as pyrite oxidizes. This problem appears to be significantly worse if any marcasite is present. The presence of pyrite in the aggregate used to make concrete can lead to severe deterioration as pyrite oxidizes. In early 2009, problems with Chinese drywall imported into the United States after Hurricane Katrina were attributed to pyrite oxidation, followed by microbial sulfate reduction which released hydrogen sulfide gas ( H 2 S ). These problems included

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1932-564: The same as a regular dodecahedron , known as pyritohedra, and this suggests an explanation for the artificial geometrical models found in Europe as early as the 5th century BC. Cattierite ( Co S 2 ), vaesite ( Ni S 2 ) and hauerite ( Mn S 2 ), as well as sperrylite ( Pt As 2 ) are similar in their structure and belong also to the pyrite group. Bravoite is a nickel-cobalt bearing variety of pyrite, with > 50% substitution of Ni for Fe within pyrite. Bravoite

1978-424: The unit. The Penn Yan is predominantly shale. Localized beds and lenses of siltstone can be found in the formation, becoming more frequent and courser moving eastward. Concretions of lime material can also be found with in the unit. The color is light to dark grey. It maybe tinted olive to greenish. Geneseo was originally proposed by Chadwick (1920, p. 118) and was defined as all of the "black" shale separating

2024-550: Was applied to several types of stone that would create sparks when struck against steel ; Pliny the Elder described one of them as being brassy, almost certainly a reference to what is now called pyrite. By Georgius Agricola 's time, c.  1550 , the term had become a generic term for all of the sulfide minerals . Pyrite is usually found associated with other sulfides or oxides in quartz veins , sedimentary rock , and metamorphic rock , as well as in coal beds and as

2070-470: Was defined by de Witt and Colton, 1959. Previously it was defined by Grossman (1944, p. 64) as a tongue of the West River Shale. In their publication de Witt and Colton demonstrated that in addition to the Genundewa Limestone, there were several other members separating the Penn Yan from the West River. The Lodi Limestone is located near the base on the Penn Yan near the eastern extent of

2116-408: Was defined by de Witt and Colton, 1959. The Sherburne occupies a much narrower footprint east/west then the three larger formations. The Sherburne has finer clastic material to the west and courser material to the east. Ranging from clay sized particles forming shales, to fine-grained sand. The bedding is thin to massive. Most bedding is 1 to 12 inches though some areas it can reach 15' The Penn Yan

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