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83-522: The A469 is a road in south Wales . It links Cardiff and Caerphilly with Rhymney and the Heads of the Valleys Road (A465) . 51°38′05″N 3°13′53″W  /  51.63469°N 3.23135°W  / 51.63469; -3.23135 This Wales road or road transport-related article is a stub . You can help Misplaced Pages by expanding it . South Wales A point of some discussion

166-434: A body-centered cubic (bcc) crystal structure . As it cools further to 1394 °C, it changes to its γ-iron allotrope, a face-centered cubic (fcc) crystal structure, or austenite . At 912 °C and below, the crystal structure again becomes the bcc α-iron allotrope. The physical properties of iron at very high pressures and temperatures have also been studied extensively, because of their relevance to theories about

249-430: A nuclear spin (− 1 ⁄ 2 ). The nuclide Fe theoretically can undergo double electron capture to Cr, but the process has never been observed and only a lower limit on the half-life of 4.4×10 years has been established. Fe is an extinct radionuclide of long half-life (2.6 million years). It is not found on Earth, but its ultimate decay product is its granddaughter, the stable nuclide Ni . Much of

332-499: A supernova for their formation, involving rapid neutron capture by starting Fe nuclei. In the far future of the universe, assuming that proton decay does not occur, cold fusion occurring via quantum tunnelling would cause the light nuclei in ordinary matter to fuse into Fe nuclei. Fission and alpha-particle emission would then make heavy nuclei decay into iron, converting all stellar-mass objects to cold spheres of pure iron. Iron's abundance in rocky planets like Earth

415-454: A distorted sodium chloride structure. The binary ferrous and ferric halides are well-known. The ferrous halides typically arise from treating iron metal with the corresponding hydrohalic acid to give the corresponding hydrated salts. Iron reacts with fluorine, chlorine, and bromine to give the corresponding ferric halides, ferric chloride being the most common. Ferric iodide is an exception, being thermodynamically unstable due to

498-583: A heritage with other ex- anthracite mining areas in eastern Carmarthenshire , as much as with the Glamorgan valleys. The local slang , dialect and phrases of the South Wales Valleys communities have been referred to as ' Wenglish ', and are often used with comic effect. The dialect is found in such coastal towns as Barry , as featured in the BBC comedy series, Gavin & Stacey . Welsh

581-553: A macroscopic piece of iron will have a nearly zero overall magnetic field. Application of an external magnetic field causes the domains that are magnetized in the same general direction to grow at the expense of adjacent ones that point in other directions, reinforcing the external field. This effect is exploited in devices that need to channel magnetic fields to fulfill design function, such as electrical transformers , magnetic recording heads, and electric motors . Impurities, lattice defects , or grain and particle boundaries can "pin"

664-475: A mixture of O 2 /Ar. Iron(IV) is a common intermediate in many biochemical oxidation reactions. Numerous organoiron compounds contain formal oxidation states of +1, 0, −1, or even −2. The oxidation states and other bonding properties are often assessed using the technique of Mössbauer spectroscopy . Many mixed valence compounds contain both iron(II) and iron(III) centers, such as magnetite and Prussian blue ( Fe 4 (Fe[CN] 6 ) 3 ). The latter

747-471: A result, mercury is traded in standardized 76 pound flasks (34 kg) made of iron. Iron is by far the most reactive element in its group; it is pyrophoric when finely divided and dissolves easily in dilute acids, giving Fe . However, it does not react with concentrated nitric acid and other oxidizing acids due to the formation of an impervious oxide layer, which can nevertheless react with hydrochloric acid . High-purity iron, called electrolytic iron ,

830-475: A series of cycle tracks and other outdoor amenities. Large areas of forestry and open moorland also contribute to the amenity of the landscape. Merthyr Tydfil ( Welsh : Merthyr Tudful ) grew around the Dowlais Ironworks which was founded to exploit the locally abundant seams of iron ore , and in time it became the largest iron-producing town in the world. New coal mines were sunk nearby to feed

913-455: A type of rock consisting of repeated thin layers of iron oxides alternating with bands of iron-poor shale and chert . The banded iron formations were laid down in the time between 3,700  million years ago and 1,800  million years ago . Materials containing finely ground iron(III) oxides or oxide-hydroxides, such as ochre , have been used as yellow, red, and brown pigments since pre-historical times. They contribute as well to

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996-435: A very large coordination and organometallic chemistry : indeed, it was the discovery of an iron compound, ferrocene , that revolutionalized the latter field in the 1950s. Iron is sometimes considered as a prototype for the entire block of transition metals, due to its abundance and the immense role it has played in the technological progress of humanity. Its 26 electrons are arranged in the configuration [Ar]3d 4s , of which

1079-695: Is a metal that belongs to the first transition series and group 8 of the periodic table . It is, by mass, the most common element on Earth , forming much of Earth's outer and inner core . It is the fourth most abundant element in the Earth's crust , being mainly deposited by meteorites in its metallic state. Extracting usable metal from iron ores requires kilns or furnaces capable of reaching 1,500 °C (2,730 °F), about 500 °C (932 °F) higher than that required to smelt copper . Humans started to master that process in Eurasia during

1162-646: Is also rarely found in basalts that have formed from magmas that have come into contact with carbon-rich sedimentary rocks, which have reduced the oxygen fugacity sufficiently for iron to crystallize. This is known as telluric iron and is described from a few localities, such as Disko Island in West Greenland, Yakutia in Russia and Bühl in Germany. Ferropericlase (Mg,Fe)O , a solid solution of periclase (MgO) and wüstite (FeO), makes up about 20% of

1245-824: Is always capitalised on motorway signs. Between the Statute of Rhuddlan of 1284 and the Laws in Wales Act 1535 , crown land in Wales formed the Principality of Wales . This was divided into a Principality of south Wales and a Principality of north Wales. The southern principality was made up of the counties of Ceredigion and Carmarthenshire , areas that had previously been part of the Welsh kingdom of Deheubarth ('the southern land'). The legal responsibility for this area lay in

1328-407: Is considered to be resistant to rust, due to its oxide layer. Iron forms various oxide and hydroxide compounds ; the most common are iron(II,III) oxide (Fe 3 O 4 ), and iron(III) oxide (Fe 2 O 3 ). Iron(II) oxide also exists, though it is unstable at room temperature. Despite their names, they are actually all non-stoichiometric compounds whose compositions may vary. These oxides are

1411-499: Is due to its abundant production during the runaway fusion and explosion of type Ia supernovae , which scatters the iron into space. Metallic or native iron is rarely found on the surface of the Earth because it tends to oxidize. However, both the Earth's inner and outer core , which together account for 35% of the mass of the whole Earth, are believed to consist largely of an iron alloy, possibly with nickel . Electric currents in

1494-474: Is experimentally well defined for pressures less than 50 GPa. For greater pressures, published data (as of 2007) still varies by tens of gigapascals and over a thousand kelvin. Below its Curie point of 770 °C (1,420 °F; 1,040 K), α-iron changes from paramagnetic to ferromagnetic : the spins of the two unpaired electrons in each atom generally align with the spins of its neighbors, creating an overall magnetic field . This happens because

1577-443: Is in Earth's crust only amounts to about 5% of the overall mass of the crust and is thus only the fourth most abundant element in that layer (after oxygen , silicon , and aluminium ). Most of the iron in the crust is combined with various other elements to form many iron minerals . An important class is the iron oxide minerals such as hematite (Fe 2 O 3 ), magnetite (Fe 3 O 4 ), and siderite (FeCO 3 ), which are

1660-401: Is not like that of Mn with its weak, spin-forbidden d–d bands, because Fe has higher positive charge and is more polarizing, lowering the energy of its ligand-to-metal charge transfer absorptions. Thus, all the above complexes are rather strongly colored, with the single exception of the hexaquo ion – and even that has a spectrum dominated by charge transfer in the near ultraviolet region. On

1743-1340: Is now a compulsory language up to GCSE level for all students who start their education in Wales. Several secondary schools offering Welsh medium education operate in this area, for example Ysgol Gyfun Llanhari in Pontyclun , Ysgol Gyfun Y Cymmer in Porth in the Rhondda , Ysgol Gyfun Rhydywaun in Penywaun in the Cynon Valley , Ysgol Gyfun Gwynllyw in Pontypool , Ysgol Gyfun Cwm Rhymni in Blackwood , Ysgol Gymraeg Plasmawr in Cardiff and Ysgol Gyfun Garth Olwg in Church Village . A significant number of people from ethnic minority communities speak another language as their first language, particularly in Cardiff and Newport. Commonly spoken languages in some areas include Punjabi , Bengali , Arabic , Somali and Chinese , and increasingly Central European languages such as Polish . In

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1826-627: Is overprinted with urban regeneration, tourism and multi-national investment. Large factory units, either empty or turned over to retail use, bear witness to the lack of success in replacing older industries. The native language of the majority of people in South Wales is English , but there are many who also speak Welsh . In western parts of Glamorgan , particularly the Neath and Swansea Valleys , there remain significant Welsh-speaking communities such as Ystradgynlais and Ystalyfera , which share

1909-407: Is possible, but nonetheless the sequence does effectively end at Ni because conditions in stellar interiors cause the competition between photodisintegration and the alpha process to favor photodisintegration around Ni. This Ni, which has a half-life of about 6 days, is created in quantity in these stars, but soon decays by two successive positron emissions within supernova decay products in

1992-548: Is somewhat different). Pieces of magnetite with natural permanent magnetization ( lodestones ) provided the earliest compasses for navigation. Particles of magnetite were extensively used in magnetic recording media such as core memories , magnetic tapes , floppies , and disks , until they were replaced by cobalt -based materials. Iron has four stable isotopes : Fe (5.845% of natural iron), Fe (91.754%), Fe (2.119%) and Fe (0.282%). Twenty-four artificial isotopes have also been created. Of these stable isotopes, only Fe has

2075-442: Is such a strong oxidizing agent that it oxidizes ammonia to nitrogen (N 2 ) and water to oxygen: The pale-violet hex aquo complex [Fe(H 2 O) 6 ] is an acid such that above pH 0 it is fully hydrolyzed: As pH rises above 0 the above yellow hydrolyzed species form and as it rises above 2–3, reddish-brown hydrous iron(III) oxide precipitates out of solution. Although Fe has a d configuration, its absorption spectrum

2158-502: Is supposed to have an orthorhombic or a double hcp structure. (Confusingly, the term "β-iron" is sometimes also used to refer to α-iron above its Curie point, when it changes from being ferromagnetic to paramagnetic, even though its crystal structure has not changed. ) The inner core of the Earth is generally presumed to consist of an iron- nickel alloy with ε (or β) structure. The melting and boiling points of iron, along with its enthalpy of atomization , are lower than those of

2241-418: Is thus very important economically, and iron is the cheapest metal, with a price of a few dollars per kilogram or pound. Pristine and smooth pure iron surfaces are a mirror-like silvery-gray. Iron reacts readily with oxygen and water to produce brown-to-black hydrated iron oxides , commonly known as rust . Unlike the oxides of some other metals that form passivating layers, rust occupies more volume than

2324-451: Is used as the traditional "blue" in blueprints . Iron is the first of the transition metals that cannot reach its group oxidation state of +8, although its heavier congeners ruthenium and osmium can, with ruthenium having more difficulty than osmium. Ruthenium exhibits an aqueous cationic chemistry in its low oxidation states similar to that of iron, but osmium does not, favoring high oxidation states in which it forms anionic complexes. In

2407-437: Is used in chemical actinometry and along with its sodium salt undergoes photoreduction applied in old-style photographic processes. The dihydrate of iron(II) oxalate has a polymeric structure with co-planar oxalate ions bridging between iron centres with the water of crystallisation located forming the caps of each octahedron, as illustrated below. Iron(III) complexes are quite similar to those of chromium (III) with

2490-558: Is whether the first element of the name should be capitalised: 'south Wales' or 'South Wales'. As the name is a geographical expression rather than a specific area with well-defined borders, style guides such as those of the BBC and The Guardian use the form 'south Wales'. In a more authoritative style guide, the Welsh Government , in their international gateway website, Wales.com, state that it should always be capitalised. It

2573-568: The 2nd millennium BC and the use of iron tools and weapons began to displace copper alloys – in some regions, only around 1200 BC. That event is considered the transition from the Bronze Age to the Iron Age . In the modern world , iron alloys, such as steel , stainless steel , cast iron and special steels , are by far the most common industrial metals, due to their mechanical properties and low cost. The iron and steel industry

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2656-586: The Forest of Dean in Gloucestershire and the tin mines of Cornwall such as Geevor Tin Mine , as a large but experienced and willing workforce was required. Whilst some of the migrants left, many settled and established in the south Wales Valleys between Swansea and Abergavenny as English-speaking communities with a unique identity. Industrial workers were housed in cottages and terraced houses close to

2739-616: The National Coal Board . These industries have since largely been replaced by service sector industries. The cities along the M4 corridor are home to a number of high-profile blue-chip companies such as Admiral Insurance , Legal & General and the Welsh-based Principality Building Society . A large number of telephone call centres are located in the region and in particular in

2822-623: The Presbyterian Church of Wales ), whose distinctive grey stone chapels can be seen in many parts. These were mainly Welsh-language congregations. Anglicanism in South Wales became autonomous from the Church of England with the Welsh Church Act 1914 , but the immediate demise of the denomination feared at that time has not taken place in the Church in Wales . There are a number of Brethren Assemblies in Cardiff and in

2905-598: The South Wales Main Line and associated branches such as the Valley Lines . Radio stations include: The Welsh national media is based in Cardiff where the BBC and ITV have their main studios and offices. 51°41′N 3°23′W  /  51.683°N 3.383°W  / 51.683; -3.383 Iron Iron is a chemical element ; it has the symbol Fe (from Latin ferrum  'iron') and atomic number 26. It

2988-527: The furnaces and in time produced coal for export. By the 1831 census, the population of Merthyr was 60,000—more at that time than Cardiff, Swansea and Newport combined—and its industries included coal mines , iron works , cable factory , engine sheds and sidings and many others. The town was also the birthplace of Joseph Parry , composer of the song Myfanwy . The Heads of the Valleys towns, including Rhymney , Tredegar and Ebbw Vale , rose out of

3071-432: The supernova remnant gas cloud, first to radioactive Co, and then to stable Fe. As such, iron is the most abundant element in the core of red giants , and is the most abundant metal in iron meteorites and in the dense metal cores of planets such as Earth . It is also very common in the universe, relative to other stable metals of approximately the same atomic weight . Iron is the sixth most abundant element in

3154-491: The trans - chlorohydridobis(bis-1,2-(diphenylphosphino)ethane)iron(II) complex is used as a starting material for compounds with the Fe( dppe ) 2 moiety . The ferrioxalate ion with three oxalate ligands displays helical chirality with its two non-superposable geometries labelled Λ (lambda) for the left-handed screw axis and Δ (delta) for the right-handed screw axis, in line with IUPAC conventions. Potassium ferrioxalate

3237-466: The universe , and the most common refractory element. Although a further tiny energy gain could be extracted by synthesizing Ni , which has a marginally higher binding energy than Fe, conditions in stars are unsuitable for this process. Element production in supernovas greatly favor iron over nickel, and in any case, Fe still has a lower mass per nucleon than Ni due to its higher fraction of lighter protons. Hence, elements heavier than iron require

3320-478: The 1870s, coal was transported by rail transport networks to Newport Docks , at the time the largest coal exporting docks in the world, and by the 1880s coal was being exported from Barry, Vale of Glamorgan . The Marquess of Bute , who owned much of the land north of Cardiff , built a steam railway system on his land that stretched from Cardiff into many of the South Wales Valleys where the coal

3403-517: The 19th and early 20th centuries, there was a vigorous literary and musical culture centred round eisteddfodau . Despite a few timid attempts to emulate this literature in English, it can be argued that few writers seem to connect with either the landscape or the literary tradition. The one exception, to some extent, can be considered to be Dylan Thomas. The South Wales landscape is marked by numerous chapels, places of worship (past and present) of

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3486-570: The 3d and 4s electrons are relatively close in energy, and thus a number of electrons can be ionized. Iron forms compounds mainly in the oxidation states +2 ( iron(II) , "ferrous") and +3 ( iron(III) , "ferric"). Iron also occurs in higher oxidation states , e.g., the purple potassium ferrate (K 2 FeO 4 ), which contains iron in its +6 oxidation state. The anion [FeO 4 ] with iron in its +7 oxidation state, along with an iron(V)-peroxo isomer, has been detected by infrared spectroscopy at 4 K after cocondensation of laser-ablated Fe atoms with

3569-569: The Bracchi, Italians in the café and catering trades often from Bardi in the Apennines. Post-war diversity has brought mosques , especially in Cardiff and Newport, Sikh gurdwaras , including one on the mountain near Abercynon and a growing number of Evangelical and Pentecostal congregations. These often add a strongly international element into local life, such as the "Pont" twinning project between Pontypridd and Mbale , Uganda , and

3652-603: The Earth's surface. Items made of cold-worked meteoritic iron have been found in various archaeological sites dating from a time when iron smelting had not yet been developed; and the Inuit in Greenland have been reported to use iron from the Cape York meteorite for tools and hunting weapons. About 1 in 20 meteorites consist of the unique iron-nickel minerals taenite (35–80% iron) and kamacite (90–95% iron). Native iron

3735-703: The Swansea area and Free Presbyterian Churches in Rhiwderin , near Newport and at Merthyr Tydfil . The Roman Catholic community, despite systematic persecution, survived in the 17th to 19th centuries, especially in Brecon and among minor gentry such as the Vaughans of Welsh Bicknor , on the Monmouthshire–Herefordshire border. Among members of foreign origin of later urban Catholic congregations were

3818-579: The Valleys area. Merthyr Tydfil is home to the principal UK call centre for German mobile telephone company, T-Mobile . Many jobs are also provided in small-scale and family businesses. One site of note on the M4 corridor is Port Talbot Steelworks – the largest steel producer in the UK and one of the biggest in Europe. The television and film sectors are fast becoming a major industry in South Wales. In 2021,

3901-486: The Welsh language, although the interests of the latter lay more in society and culture than in the evocation of natural scenery. This natural environment changed to a considerable extent during the early Industrial Revolution when the Glamorgan and Monmouthshire valley areas were exploited for coal and iron . By the 1830s, hundreds of tons of coal were being transported by barge to ports in Cardiff and Newport . In

3984-437: The Welsh screen sector saw a turnover of £575 million. Prominent film studios have been established in Cardiff (Wolf Studios Wales, Seren Stiwdios, Enfys Studios) as well as Bridgend (Dragon Studios) and Swansea (Bay Studios). Great Western Railway operate services from Swansea , Cardiff Central and Newport to London Paddington with Class 800s . Most services in South Wales are operated by Transport for Wales Rail on

4067-450: The brown deposits present in a sizeable number of streams. Due to its electronic structure, iron has a very large coordination and organometallic chemistry. Many coordination compounds of iron are known. A typical six-coordinate anion is hexachloroferrate(III), [FeCl 6 ] , found in the mixed salt tetrakis(methylammonium) hexachloroferrate(III) chloride . Complexes with multiple bidentate ligands have geometric isomers . For example,

4150-661: The color of various rocks and clays , including entire geological formations like the Painted Hills in Oregon and the Buntsandstein ("colored sandstone", British Bunter ). Through Eisensandstein (a jurassic 'iron sandstone', e.g. from Donzdorf in Germany) and Bath stone in the UK, iron compounds are responsible for the yellowish color of many historical buildings and sculptures. The proverbial red color of

4233-464: The cores of the Earth and other planets. Above approximately 10 GPa and temperatures of a few hundred kelvin or less, α-iron changes into another hexagonal close-packed (hcp) structure, which is also known as ε-iron . The higher-temperature γ-phase also changes into ε-iron, but does so at higher pressure. Some controversial experimental evidence exists for a stable β phase at pressures above 50 GPa and temperatures of at least 1500 K. It

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4316-579: The creation of "Fairtrade" relationships with primary producers worldwide. The former heavy industries of coal and iron production have disappeared since the economic struggles of the 1970s, with the closures of that decade continuing sharply into the 1980s, and by July 1985 just 31 coal pits remained in the region. Further closures left the region with just one deep mine by the early 1990s, and this finally closed in January 2008, by which time it had transferred to private ownership after being sold off by

4399-401: The domains in the new positions, so that the effect persists even after the external field is removed – thus turning the iron object into a (permanent) magnet . Similar behavior is exhibited by some iron compounds, such as the ferrites including the mineral magnetite , a crystalline form of the mixed iron(II,III) oxide Fe 3 O 4 (although the atomic-scale mechanism, ferrimagnetism ,

4482-479: The earlier 3d elements from scandium to chromium , showing the lessened contribution of the 3d electrons to metallic bonding as they are attracted more and more into the inert core by the nucleus; however, they are higher than the values for the previous element manganese because that element has a half-filled 3d sub-shell and consequently its d-electrons are not easily delocalized. This same trend appears for ruthenium but not osmium . The melting point of iron

4565-406: The exception of iron(III)'s preference for O -donor instead of N -donor ligands. The latter tend to be rather more unstable than iron(II) complexes and often dissociate in water. Many Fe–O complexes show intense colors and are used as tests for phenols or enols . For example, in the ferric chloride test , used to determine the presence of phenols, iron(III) chloride reacts with a phenol to form

4648-595: The giant coal tip unstable, resulting in the Aberfan disaster . The recent dumping of small particles of coal and ash known as 'tailings' seems to have been partly responsible. A 30-foot-high (9 m) black wave tore downhill across the Glamorganshire Canal and swept away houses on its path towards the village school. 114 children and 28 adults were killed. The Rhondda Valleys (Rhondda Fach and Rhondda Fawr) housed around 3,000 people in 1860, but by 1910

4731-462: The global stock of iron in use in society is 2,200 kg per capita. More-developed countries differ in this respect from less-developed countries (7,000–14,000 vs 2,000 kg per capita). Ocean science demonstrated the role of the iron in the ancient seas in both marine biota and climate. Iron shows the characteristic chemical properties of the transition metals , namely the ability to form variable oxidation states differing by steps of one and

4814-671: The hands of the Justiciar of South Wales based at Carmarthen . Other parts of southern Wales were in the hands of various Marcher Lords . The Laws in Wales Acts 1542 created the Court of Great Sessions in Wales based on four legal circuits. The Brecon circuit served the counties of Brecknockshire , Radnorshire and Glamorgan while the Carmarthen circuit served Cardiganshire, Carmarthenshire and Pembrokeshire . Monmouthshire

4897-399: The industrial revolution, producing coal, metal ores and later steel . Aberfan : The Merthyr Vale colliery began to produce coal in 1875. Spoil from the mine workings was piled on the hills close to the village which grew nearby. Tipping went on until the 1960s. Although nationalised, the National Coal Board failed to appreciate the danger they had created. In October 1966, heavy rain made

4980-453: The liquid outer core are believed to be the origin of the Earth's magnetic field . The other terrestrial planets ( Mercury , Venus , and Mars ) as well as the Moon are believed to have a metallic core consisting mostly of iron. The M-type asteroids are also believed to be partly or mostly made of metallic iron alloy. The rare iron meteorites are the main form of natural metallic iron on

5063-446: The literature, this mineral phase of the lower mantle is also often called magnesiowüstite. Silicate perovskite may form up to 93% of the lower mantle, and the magnesium iron form, (Mg,Fe)SiO 3 , is considered to be the most abundant mineral in the Earth, making up 38% of its volume. While iron is the most abundant element on Earth, most of this iron is concentrated in the inner and outer cores. The fraction of iron that

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5146-407: The major ores of iron . Many igneous rocks also contain the sulfide minerals pyrrhotite and pentlandite . During weathering , iron tends to leach from sulfide deposits as the sulfate and from silicate deposits as the bicarbonate. Both of these are oxidized in aqueous solution and precipitate in even mildly elevated pH as iron(III) oxide . Large deposits of iron are banded iron formations ,

5229-775: The metal and thus flakes off, exposing more fresh surfaces for corrosion. Chemically, the most common oxidation states of iron are iron(II) and iron(III) . Iron shares many properties of other transition metals, including the other group 8 elements , ruthenium and osmium . Iron forms compounds in a wide range of oxidation states , −4 to +7. Iron also forms many coordination compounds ; some of them, such as ferrocene , ferrioxalate , and Prussian blue have substantial industrial, medical, or research applications. The body of an adult human contains about 4 grams (0.005% body weight) of iron, mostly in hemoglobin and myoglobin . These two proteins play essential roles in oxygen transport by blood and oxygen storage in muscles . To maintain

5312-612: The meteorites Semarkona and Chervony Kut, a correlation between the concentration of Ni, the granddaughter of Fe, and the abundance of the stable iron isotopes provided evidence for the existence of Fe at the time of formation of the Solar System . Possibly the energy released by the decay of Fe, along with that released by Al , contributed to the remelting and differentiation of asteroids after their formation 4.6 billion years ago. The abundance of Ni present in extraterrestrial material may bring further insight into

5395-586: The mines and foundries in which they worked. The large influx over the years caused overcrowding which led to outbreaks of Cholera , and on the social and cultural side, the near-loss of the Welsh language in the area. The 1930s inter-war Great Depression in the United Kingdom saw the loss of almost half of the coal pits in the South Wales Coalfield , and their number declined further in

5478-559: The necessary levels, human iron metabolism requires a minimum of iron in the diet. Iron is also the metal at the active site of many important redox enzymes dealing with cellular respiration and oxidation and reduction in plants and animals. At least four allotropes of iron (differing atom arrangements in the solid) are known, conventionally denoted α , γ , δ , and ε . The first three forms are observed at ordinary pressures. As molten iron cools past its freezing point of 1538 °C, it crystallizes into its δ allotrope, which has

5561-436: The orbitals of those two electrons (d z and d x − y ) do not point toward neighboring atoms in the lattice, and therefore are not involved in metallic bonding. In the absence of an external source of magnetic field, the atoms get spontaneously partitioned into magnetic domains , about 10 micrometers across, such that the atoms in each domain have parallel spins, but some domains have other orientations. Thus

5644-539: The origin and early history of the Solar System . The most abundant iron isotope Fe is of particular interest to nuclear scientists because it represents the most common endpoint of nucleosynthesis . Since Ni (14 alpha particles ) is easily produced from lighter nuclei in the alpha process in nuclear reactions in supernovae (see silicon burning process ), it is the endpoint of fusion chains inside extremely massive stars . Although adding more alpha particles

5727-444: The other hand, the pale green iron(II) hexaquo ion [Fe(H 2 O) 6 ] does not undergo appreciable hydrolysis. Carbon dioxide is not evolved when carbonate anions are added, which instead results in white iron(II) carbonate being precipitated out. In excess carbon dioxide this forms the slightly soluble bicarbonate, which occurs commonly in groundwater, but it oxidises quickly in air to form iron(III) oxide that accounts for

5810-581: The oxidizing power of Fe and the high reducing power of I : Ferric iodide, a black solid, is not stable in ordinary conditions, but can be prepared through the reaction of iron pentacarbonyl with iodine and carbon monoxide in the presence of hexane and light at the temperature of −20 °C, with oxygen and water excluded. Complexes of ferric iodide with some soft bases are known to be stable compounds. The standard reduction potentials in acidic aqueous solution for some common iron ions are given below: The red-purple tetrahedral ferrate (VI) anion

5893-497: The past work on isotopic composition of iron has focused on the nucleosynthesis of Fe through studies of meteorites and ore formation. In the last decade, advances in mass spectrometry have allowed the detection and quantification of minute, naturally occurring variations in the ratios of the stable isotopes of iron. Much of this work is driven by the Earth and planetary science communities, although applications to biological and industrial systems are emerging. In phases of

5976-546: The population had soared to 160,000. The Rhondda had become the heart of a massive South Wales coal industry. Mining accidents below ground were common, and in 1896 fifty-seven men and boys were killed in a gas explosion at the Tylorstown Colliery . An enquiry found that the pit involved had not been properly inspected over the previous 15 months. Ebbw Vale, the valley of the Ebbw River which stretches from

6059-414: The principal ores for the production of iron (see bloomery and blast furnace). They are also used in the production of ferrites , useful magnetic storage media in computers, and pigments. The best known sulfide is iron pyrite (FeS 2 ), also known as fool's gold owing to its golden luster. It is not an iron(IV) compound, but is actually an iron(II) polysulfide containing Fe and S 2 ions in

6142-437: The second half of the 3d transition series, vertical similarities down the groups compete with the horizontal similarities of iron with its neighbors cobalt and nickel in the periodic table, which are also ferromagnetic at room temperature and share similar chemistry. As such, iron, cobalt, and nickel are sometimes grouped together as the iron triad . Unlike many other metals, iron does not form amalgams with mercury . As

6225-629: The status of Breconshire or Carmarthenshire, for instance, is more debatable. In the western extent, from Swansea westwards, local people might feel that they live in both south Wales and west Wales . Areas to the north of the Brecon Beacons and Black Mountains are generally considered to be in Mid Wales. The valleys and upland mountain ridges were once a very rural area noted for its river valleys and ancient forests and lauded by romantic poets such as William Wordsworth as well as poets in

6308-564: The surface of Mars is derived from an iron oxide-rich regolith . Significant amounts of iron occur in the iron sulfide mineral pyrite (FeS 2 ), but it is difficult to extract iron from it and it is therefore not exploited. In fact, iron is so common that production generally focuses only on ores with very high quantities of it. According to the International Resource Panel 's Metal Stocks in Society report ,

6391-529: The theological innovations of some trained ministers, and created new congregations such as that at Hengoed near Ystrad Mynach . In the same century, churches were sometimes involved in the Methodist movement, especially at Groeswen and Watford near Caerphilly , which both received frequent visits from John Wesley The largest denomination, however, became the Calvinist Methodists (later

6474-417: The town of Ebbw Vale to Newport, includes the mining towns and villages of Newbridge , Risca , Crumlin , Abercarn and Cwmcarn . The Carboniferous Black Vein coal seams in the area lay some 900 feet (275 metres) below the surface and the mining activity associated with it was responsible for many tragic subsurface explosions, roof collapses and mining accidents . Now the Valleys' heavy industrial past

6557-599: The various Christian Nonconformist congregations. The Baptist congregation at Ilston , Gower , moved to Swansea, Massachusetts , but after the restoration of the Anglican worship with the issue of the Book of Common Prayer in 1662, several "gathered" churches survived belonging to the Baptist, Independent and Presbyterian denominations. In the 18th century members of some of these congregations became dissatisfied with

6640-455: The volume of the lower mantle of the Earth, which makes it the second most abundant mineral phase in that region after silicate perovskite (Mg,Fe)SiO 3 ; it also is the major host for iron in the lower mantle. At the bottom of the transition zone of the mantle, the reaction γ- (Mg,Fe) 2 [SiO 4 ] ↔ (Mg,Fe)[SiO 3 ] + (Mg,Fe)O transforms γ-olivine into a mixture of silicate perovskite and ferropericlase and vice versa. In

6723-774: The years following World War II . This number is now very low, following the UK miners' strike (1984–85) , and the last 'traditional' deep-shaft mine, Tower Colliery , closed in January 2008. Despite the intense industrialisation of the coal mining valleys, many parts of the landscape of South Wales such as the upper Neath valley, the Vale of Glamorgan and the valleys of the River Usk and River Wye remain distinctly beautiful and unspoilt and have been designated Sites of Special Scientific Interest . In addition, many once heavily industrialised sites have reverted to wilderness, some provided with

6806-773: Was attached to the Oxford circuit for judicial purposes. These seven southern counties were thus differentiated from the six counties of north Wales. The Court of the Great Sessions came to an end in 1830, but the counties survived until the Local Government Act 1972 which came into operation in 1974. The creation of the county of Powys merged one northern county ( Montgomeryshire ) with two southern ones (Breconshire and Radnorshire). There are thus different concepts of south Wales. Glamorgan and Monmouthshire are generally accepted by all as being in south Wales. But

6889-459: Was being found. Lord Bute then charged fees per ton of coal that was transported out using his railways. With coal mining and iron smelting being the main trades of south Wales, many thousands of immigrants from the Midlands , Scotland , Ireland , Cornwall and even Italy came and set up homes and put down roots in the region. Very many came from other coal mining areas such as Somerset ,

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