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Scandium is a chemical element with symbol Sc and atomic number 21. A silvery-white metallictransition metal, it has historically been sometimes classified as a rare earth element, together with yttrium and thelanthanoids. It was discovered in 1879 by spectral analysis, of the minerals euxenite and gadolinite from Scandinavia.HP Pavilion DV4 Battery

Scandium is present in most of the deposits of rare earth and uranium compounds, but it is extracted from these ores in only a few mines worldwide. Because of the low availability and the difficulties in the preparation of metallic scandium, which was first done in 1937, it took until the 1970s before applications for scandium were developed.HP Pavilion DV4-1000 Battery

The positive effects of scandium on aluminium alloys were discovered in the 1970s, and its use in such alloys remains its only major application.

The properties of scandium compounds are intermediate between those of aluminium and yttrium. HP Pavilion DV4-1000EA Battery

A diagonal relationship exists between the behavior of magnesium and scandium, just as there is between beryllium and aluminium. In the chemical compounds of the elements shown as group 3, above, the predominant oxidation state is +3.HP Pavilion DV4-1000ET Battery

Chemical characteristics of the element

Scandium metal is soft metal with a silvery appearance. It develops a slightly yellowish or pinkish cast when oxidized by air. It is susceptible to weathering and dissolves slowly in most dilute acids. It does not react with a 1:1 mixture ofnitric acid (HNO3) and hydrofluoric acid (HF), possibly due to the formation of an impermeable passive layer.HP Pavilion DV4-1001 Battery

Scandium exists naturally exclusively as the isotope 45Sc, which has a nuclear spin of 7/2. Thirteen radioisotopes have been characterized with the most stable being 46Sc with a half-life of 83.8 days, 47Sc with a half-life of 3.35 days, and 48Sc with a half-life of 43.7 hours. HP Pavilion DV4-1001AX Battery

All of the remaining radioactive isotopes have half-lives that are less than 4 hours, and the majority of these have half-lives that are less than 2 minutes. This element also has five meta states with the most stable being 44mSc (t½ = 58.6 h).[3]

The isotopes of scandium range from 36Sc to 60Sc. HP Pavilion DV4-1001TU Battery

The primary decay mode at masses lower than the only stable isotope, 45Sc, is electron capture, and the primary mode at masses above it is beta emission. The primary decay products at atomic weights below 45Sc are calcium isotopes and the primary products from higher atomic weights are titanium isotopes.HP Pavilion DV4-1001TX Battery

Occurrence

In terms of earth's crust, scandium is not particularly rare, Estimates vary from 18 to 25 ppm, which is comparable to the abundance of cobalt (20–30 ppm). Scandium is only the 50th most common element on earth (35th most abundant in the crust, but it is the 23rd most common element in the sun).HP Pavilion DV4-1002 Battery

However, scandium is distributed sparsely and occurs in trace amounts in many minerals.[5] Rare minerals from Scandinavia[6]and Madagascar[7] such as thortveitite, euxenite, and gadolinite are the only known concentrated sources of this element. Thortveitite can contain up to 45% of scandium in the form ofscandium(III) oxide.HP Pavilion DV4-1002AX Battery

The stable form of scandium is created in supernovas via the r-process.

Production

World production of scandium is in the order of 2 tonnes per year in the form of scandium oxide. The primary production is 400 kg while the rest is from stockpiles of Russia generated during the Cold War. HP Pavilion DV4-1002TU Battery

In 2003, only three mines produced scandium: the uranium and iron mines in Zhovti Vody in Ukraine, the rare earth mines in Bayan Obo, China and the apatite mines in the Kola peninsula, Russia. In each case, scandium is a byproduct from the extraction of other elements[9] and is sold as scandium oxide.HP Pavilion DV4-1002TX Battery

The production of metallic scandium is in the order of 10 kg per year.[9][10] The oxide is converted to scandium fluoride andreduced with metallic calcium.

Madagascar and Iveland-Evje region in Norway have the only deposits of minerals with high scandium content, thortveitite(Sc,Y)2(Si2O7) and kolbeckite ScPO4·2H2O, but these are not being exploited.HP Pavilion DV4-1003AX Battery

The absence of reliable, secure, stable and long term production has limited commercial applications of scandium. Despite this low level of use, scandium offers significant benefits. Particularly promising is the strengthening of aluminium alloys with as little as 0.5% scandium. HP Pavilion DV4-1003TU Battery

Scandium-stabilized zirconia enjoys a growing market demand for use as a high efficiency electrolyte in solid oxide fuel cells.

Compounds

The chemistry is almost completely dominated by the trivalent ion, Sc3+. The radii of M3+ ions in the table below indicate that in terms of chemical properties, scandium ions are more similar to those of yttrium than to those of aluminium. In part for this similarity, scandium is often classified as a lanthanide-like element.HP Pavilion DV4-1003TX Battery

Oxides and hydroxides

The oxide Sc2O3 and the hydroxide Sc(OH)3 are amphoteric:[11]

Sc(OH)3 + 3 OH? ? Sc(OH)3?
6

Sc(OH)3 + 3 H+ + 3 H2O ? [Sc(H2O)6]3+

The ?- and ?- forms of scandium oxide hydroxide (ScO(OH)), are isostructural with their aluminium oxide hydroxidecounterparts.[12] Solutions of Sc3+ in water are acidic because of hydrolysis.HP Pavilion DV4-1004AX Battery

Halides and pseudohalides

The halides ScX3 (X = Cl, Br, I) are very soluble in water, but ScF3 is insoluble. In all four halides the scandium is 6-coordinated. The halides are Lewis acids; for example, ScF3 dissolves a solution containing excess fluoride to form [ScF6]3?. The coordination number 6 is typical of Sc(III). HP Pavilion DV4-1004TU Battery

In the larger Y3+ and La3+ ions, coordination numbers of 8 and 9 are common.Scandium(III) triflate is sometimes used as a Lewis acid catalyst in organic chemistry.

Organic derivatives

Scandium forms a series of organometallic compounds with cyclopentadienyl ligands (Cp), similar to the behavior of the lanthanide.HP Pavilion DV4-1004TX Battery

One example is the chlorine-bridged dimer, [ScCp2Cl]2 and related derivatives of pentamethylcyclopentadienylligands.[13]

Uncommon oxidation states

Compounds that feature scandium in the oxidation state other than +3 are rare but well characterized. The blue-black compound CsScCl3 is one of the simplest. HP Pavilion DV4-1005TX Battery

This material adopts a sheet-like structure that exhibits extensive bonding between the scandium(II) centers.[14] Scandium hydride is not well understood, although it appears not to be a saline hydride of Sc(II). As is observed for most elements, a diatomic scandium hydride has been observed spectroscopically at high temperatures in the gas phase.HP Pavilion DV4-1006TX Battery

Scandium borides and carbides are non-stoichiometric, as is typical for neighboring elements.

Dmitri Mendeleev, creator of the periodic table, predicted the existence of an element ekaboron, with an atomic mass between 40 and 48 in 1869. HP Pavilion DV4-1007TX Battery

Lars Fredrik Nilsonand his team detected this element in the minerals euxenite and gadolinite. Nilson prepared 2 grams of scandium oxide of high purity.[16][17] He named the element scandium, from the Latin Scandia meaning "Scandinavia". Nilson was apparently unaware of Mendeleev's prediction, but Per Teodor Cleve recognized the correspondence and notified Mendeleev.HP Pavilion DV4-1008TX Battery

Metallic scandium was produced for the first time in 1937 by electrolysis of a eutectic mixture, at 700–800 °C, of potassium, lithium, and scandium chlorides.[19]The first pound of 99% pure scandium metal was produced in 1960. The use for aluminium alloys began in 1971, following a US patent.[20] Aluminium-scandium alloys were also developed in the USSR.HP Pavilion DV4-1009TX Battery

The addition of scandium to aluminium limits the excessive grain growth that occurs in the heat-affected zone of welded aluminium components. This has two beneficial effects: the precipitated Al3Sc forms smaller crystals than are formed in other aluminium alloysand the volume of precipitate-free zones that normally exist at the grain boundaries of age-hardening aluminium alloys is reduced.HP Pavilion DV4-1010TX Battery

Both of these effects increase the usefulness of the alloy. However, titanium alloys, which are similar in lightness and strength, are cheaper and much more widely used.[23]

The main application of scandium by weight is in aluminium-scandium alloys for minor aerospace industry components. These alloys contain between 0.1% and 0.5% of scandium. HP Pavilion DV4-1011TX Battery

They were used in the Russian military aircraft, specifically the MiG-21 and MiG-29.

Some items of sports equipment, which rely on high performance materials, have been made with scandium-aluminium alloys, includingbaseball bats,[24] and bicycle[25] frames and components. Lacrosse sticks are also made with scandium-titanium alloys to take advantage of the strength of titanium. HP Pavilion DV4-1012TX Battery

The American firearm manufacturing company Smith & Wesson produces revolvers with frames composed of scandium alloy and cylinders of titanium or carbon steel.

Approximately 20 kg (as Sc2O3) of scandium is used annually in the United States to make high-intensity discharge lamps.HP Pavilion DV4-1013TX Battery

Scandium iodide, along with sodium iodide, when added to a modified form of mercury-vapor lamp, produces a form of metal halide lamp. This lamp is a white light source with high color rendering indexthat sufficiently resembles sunlight to allow good color-reproduction with TV cameras.HP Pavilion DV4-1014NR Battery

About 80 kg of scandium is used in metal halide lamps/light bulbs globally per year. The first scandium-based metal halide lamps were patented by General Electric and initially made in North America, although they are now produced in all major industrialized countries. HP Pavilion DV4-1014TX Battery

The radioactive isotope 46Sc is used in oil refineries as a tracing agent.[28] Scandium triflate is a catalytic Lewis acid used inorganic chemistry.[30]

Health and safety

Elemental scandium is considered non-toxic and little animal testing of scandium compounds has been done.HP Pavilion DV4-1015TX Battery

The median lethal dose (LD50) levels for scandium(III) chloride for rats have been determined as 4 mg/kg for intraperitoneal and 755 mg/kg for oral administration.[32] In the light of these results compounds of scandium should be handled as compounds of moderate toxicity.HP Pavilion DV4-1015TX Battery

Naturally occurring scandium (Sc) is composed of one stable isotope 45Sc. Twenty-four radioisotopes have been characterized with the most stable being 46Sc with ahalf-life of 83.8 days, 47Sc with a half-life of 3.35 days, and 48Sc with a half-life of 43.7 hours.HP Pavilion DV4-1016TX Battery

All of the remaining radioactive isotopes have half-lives that are less than four hours, and the majority of these have half-lives that are less than two minutes, the least stable being 39Sc with a half-life shorter than 300 nanoseconds. The half-lives for isotopes with mass numbers less than 39 is unknown. HP Pavilion DV4-1017TX Battery

This element also has 10 meta states with the most stable being 44mSc (t½ 58.6 h).

The isotopes of scandium range in atomic weight from 36 u (36Sc) to 60 u (60Sc). The primary decay mode at masses lower than the only stable isotope, 45Sc, is Beta-plus or electron capture, and the primary mode at masses above it is beta-minus. HP Pavilion DV4-1018TX Battery

The primary decay products at atomic weights below 45Sc are calcium isotopes and the primary products from higher atomic weights are titanium isotopes.

As defined by IUPAC, rare earth elements or rare earth metals are a set of seventeen chemical elements in the periodic table, specifically the fifteen lanthanides plus scandium and yttrium.HP Pavilion DV4-1019TX Battery

Scandium and yttrium are considered rare earth elements since they tend to occur in the same ore deposits as the lanthanides and exhibit similar chemical properties.

Despite their name, rare earth elements (with the exception of the radioactive promethium) are relatively plentiful in the Earth's crust, with cerium being the 25th most abundant element at 68 parts per million (similar to copper). HP Pavilion DV4-1020TX Battery

However, because of their geochemical properties, rare earth elements are typically dispersed and not often found in concentrated and economically exploitable forms. The few economically exploitable deposits are known as rare earth minerals.[3] It was the very scarcity of these minerals (previously called "earths") that led to the term "rare earth". HP Pavilion DV4-1020US Battery

The first such mineral discovered was gadolinite, acompound of cerium, yttrium, iron, silicon and other elements. This mineral was extracted from a mine in the village of Ytterby inSweden; many of the rare earth elements bear names derived from this location.HP Pavilion DV4-1021TX Battery

A table listing the seventeen rare earth elements, their atomic number and symbol, the etymology of their names, and their main usages (see also Lanthanide#Technological_applications) is provided here. Some of the rare earths are named for the scientists who discovered or elucidated their elemental properties, and some for their geographical discovery.HP Pavilion DV4-1022TX Battery

Discovery and early history

Rare earth elements became known to the world with the discovery of the black mineral "ytterbite" (renamed to gadolinite in 1800) by Lieutenant Carl Axel Arrheniusin 1787, at a quarry in the village of Ytterby, Sweden.HP Pavilion DV4-1023TX Battery

Arrhenius' "ytterbite" reached Johan Gadolin, a Royal Academy of Turku professor, and his analysis yielded an unknown oxide (earth) which he called Ytteria. Anders Gustav Ekeberg isolated beryllium from the gadolinite but failed to recognize other elements which the ore contained. HP Pavilion DV4-1024TX Battery

After this discovery in 1794 a mineral fromBastnäs near Riddarhyttan, Sweden, which was believed to be an iron-tungsten mineral, was re-examined by Jöns Jacob Berzelius and Wilhelm Hisinger. In 1803 they obtained a white oxide and called it ceria. Martin Heinrich Klaproth independently discovered the same oxide and called it ochroia.HP Pavilion DV4-1025TX Battery

Thus by 1803 there were two known rare earth elements, yttrium and cerium, although it took another 30 years for researchers to determine that other elements were contained in the two ores ceria and ytteria (the similarity of the rare earth metals' chemical properties made their separation difficult).HP Pavilion DV4-1026TX Battery

In 1839 Carl Gustav Mosander, an assistant of Berzelius, separated ceria by heating the nitrate and dissolving the product in nitric acid. He called the oxide of the soluble salt lanthana. It took him three more years to separate the lanthana further into didymia and pure lanthana. Didymia, although not further separable by Mosander's techniques was a mixture of oxides.HP Pavilion DV4-1027TX Battery

In 1842 Mosander also separated the ytteria into three oxides: pure ytteria, terbia and erbia (all the names are derived from the town name "Ytterby"). The earth giving pink salts he called terbium; the one which yielded yellow peroxide he called erbium.

So in 1842 the number of rare earth elements had reached six: yttrium, cerium, lanthanum, didymium, erbium and terbium.HP Pavilion DV4-1028TX Battery

Nils Johan Berlin and Marc Delafontaine tried also to separate the crude ytteria and found the same substances that Mosander obtained, but Berlin named (1860) the substance giving pink salts erbium and Delafontaine named the substance with the yellow peroxide terbium.HP Pavilion DV4-1028US Battery

This confusion led to several false claims of new elements, such as the mosandrium of J. Lawrence Smith, or the philippiumand decipium of Delafontaine.

There were no further discoveries for 30 years, and the element didymium was listed in the periodic table of elements with a molecular mass of 138. HP Pavilion DV4-1029TX Battery

In 1879 Delafontaine used the new physical process of optical-flame spectroscopy, and he found several new spectral lines in didymia. Also in 1879, the new element samariumwas isolated by Paul Émile Lecoq de Boisbaudran from the mineral samarskite.HP Pavilion DV4-1030EE Battery

The samaria earth was further separated by Lecoq de Boisbaudran in 1886 and a similar result was obtained by Jean Charles Galissard de Marignac by direct isolation from samarskite. They named the element gadolinium after Johan Gadolin, and its oxide was named "gadolinia".HP Pavilion DV4-1030EI Battery

Further spectroscopic analysis between 1886 and 1901 of samaria, ytteria, and samarskite by William Crookes, Lecoq de Boisbaudran and Eugène-Anatole Demarçay yielded several new spectroscopic lines that indicated the existence of an unknown element. The fractional crystallization of the oxides then yielded europium in 1901.HP Pavilion DV4-1030EJ Battery

In 1839 the third source for rare earths became available. This is a mineral similar to gadolinite, uranotantalum (now called "samarskite"). This mineral from Miassin the southern Ural Mountains was documented by Gustave Rose. The Russian chemist R.HP Pavilion DV4-1030EN Battery

Harmann proposed that a new element he called "ilmenium" should be present in this mineral, but later, Christian Wilhelm Blomstrand, Galissard de Marignac, and Heinrich Rose found only tantalum and niobium (columbium) in it.

The exact number of rare earth elements that existed was highly unclear, and a maximum number of 25 was estimated. HP Pavilion DV4-1030TX Battery

The use of X-ray spectra (obtained by X-ray crystallography) by Henry Gwyn Jeffreys Moseley made it possible to assign atomic numbers to the elements. Moseley found that the exact number of lanthanides had to be 15 and that element 61 had yet to be discovered.HP Pavilion DV4-1031TX Battery

Using these facts about atomic numbers from X-ray crystallography, Moseley also showed that hafnium (element 72) would not be a rare earth element. Moseley was killed in World War I in 1915, years before hafnium was discovered. Hence, the claim of Georges Urbain that he had discovered element 72 was untrue. HP Pavilion DV4-1032TX Battery

Hafnium is an element that lies in the periodic table immediately below zirconium, and hafnium and zirconium are very similar in their chemical and physical properties.

During the 1940s, Frank Spedding and others in the United States (during the Manhattan Project) developed the chemical ion exchange procedures for separating and purifying the rare earth elements. HP Pavilion DV4-1033TX Battery

This method was first applied to the actinides for separating plutonium-239 and neptunium, from uranium, thorium, actinium, and the other actinide rare earths in the materials produced in nuclear reactors. The plutonium-239 was very desirable because it is a fissile material.HP Pavilion DV4-1034TX Battery

The principal sources of rare earth elements are the minerals bastnäsite, monazite, and loparite and the lateritic ion-adsorption clays. Despite their high relative abundance, rare earth minerals are more difficult to mine and extract than equivalent sources of transition metals (due in part to their similar chemical properties), making the rare earth elements relatively expensive.HP Pavilion DV4-1035LA Battery

Their industrial use was very limited until efficient separation techniques were developed, such asion exchange, fractional crystallization and liquid-liquid extraction during the late 1950s and early 1960s.

Origin

Rare earth elements are heavier than iron and thus are produced by supernova nucleosynthesis or the s-process in asymptotic giant branch stars.HP Pavilion DV4-1035TX Battery

In nature,spontaneous fission of uranium-238 produces trace amounts of radioactive promethium, but most promethium is synthetically produced in nuclear reactors.

Geological distribution

Rare earth cerium is actually the 25th most abundant element in the Earth's crust, having 68 parts per million (about as common as copper). Only the highly unstable and radioactivepromethium "rare earth" is quite scarce.HP Pavilion DV4-1036TX Battery

The rare earth elements are often found together. The longest-lived isotope of promethium has a half life of 17.7 years, so the element only exists in nature in negligible amounts (approximately 572 g in the entire Earth's crust). Promethium is one of the two elements that do not have stable (non-radioactive) isotopes and are followed by (i.e. with higher atomic number) stable elements.HP Pavilion DV4-1037TX Battery

Due to lanthanide contraction, yttrium, which is trivalent, is of similar ionic size todysprosium and its lanthanide neighbors. Due to the relatively gradual decrease in ionic size with increasing atomic number, the rare earth elements have always been difficult to separate. HP Pavilion DV4-1038TX Battery

Even with eons of geological time, geochemical separation of the lanthanides has only rarely progressed much farther than a broad separation between light versus heavy lanthanides, otherwise known as the cerium and yttrium earths. This geochemical divide is reflected in the first two rare earths that were discovered, yttria in 1794 and ceria in 1803. HP Pavilion DV4-1039TX Battery

As originally found, each comprised the entire mixture of the associated earths. Rare earth minerals, as found, usually are dominated by one group or the other, depending upon which size-range best fits the structural lattice. Thus, among the anhydrous rare earth phosphates, it is the tetragonal mineral xenotime that incorporates yttrium and the yttrium earths, whereas the monoclinic monazite phase incorporates cerium and the cerium earths preferentially.HP Pavilion DV4-1040EE Battery

The smaller size of the yttrium group allows it a greater solid solubility in the rock-forming minerals that comprise the Earth's mantle, and thus yttrium and the yttrium earths show less enrichment in the Earth's crust relative to chondritic abundance, than does cerium and the cerium earths. HP Pavilion DV4-1040EI Battery

This has economic consequences: large ore bodies of the cerium earths are known around the world, and are being exploited. Corresponding orebodies for yttrium tend to be rarer, smaller, and less concentrated. Most of the current supply of yttrium originates in the "ion adsorption clay" ores of Southern China.HP Pavilion DV4-1040TX Battery

Some versions provide concentrates containing about 65% yttrium oxide, with the heavy lanthanides being present in ratios reflecting the Oddo-Harkins rule: even-numbered heavy lanthanides at abundances of about 5% each, and odd-numbered lanthanides at abundances of about 1% each. Similar compositions are found in xenotime or gadolinite.HP Pavilion DV4-1041TX Battery

Well-known minerals containing yttrium include gadolinite, xenotime, samarskite, euxenite, fergusonite, yttrotantalite, yttrotungstite, yttrofluorite (a variety offluorite), thalenite, yttrialite. Small amounts occur in zircon, which derives its typical yellow fluorescence from some of the accompanying heavy lanthanides. HP Pavilion DV4-1042TX Battery

Thezirconium mineral eudialyte, such as is found in southern Greenland, contains small but potentially useful amounts of yttrium. Of the above yttrium minerals, most played a part in providing research quantities of lanthanides during the discovery days. HP Pavilion DV4-1043TX Battery

Xenotime is occasionally recovered as a byproduct of heavy sand processing, but is not as abundant as the similarly recovered monazite (which typically contains a few percent of yttrium). Uranium ores from Ontario have occasionally yielded yttrium as a byproduct.HP Pavilion DV4-1044TX Battery

Well-known minerals containing cerium and the light lanthanides include bastnaesite, monazite, allanite, loparite, ancylite, parisite, lanthanite, chevkinite,cerite, stillwellite, britholite, fluocerite, and cerianite. Monazite (marine sands from Brazil, India, or Australia; rock from South Africa), bastnaesite (fromMountain Pass, California, or several localities in China), and loparite (Kola Peninsula, Russia) have been the principal ores of cerium and the light lanthanides.HP Pavilion DV4-1045TX Battery

In 2011, Yasuhiro Kato, a geologist at the University of Tokyo who led a study of Pacific Ocean seabed mud, published results indicating the mud could hold rich concentrations of rare earth minerals. The deposits, studied at 78 sites, came from "[h]ot plumes from hydrothermal vents pull[ing] these materials out of seawater and deposit[ing] them on the seafloor,HP Pavilion DV4-1046TX Battery

bit by bit, over tens of millions of years. One square patch of metal-rich mud 2.3 kilometers wide might contain enough rare earths to meet most of the global demand for a year, Japanese geologists report July 3 in Nature Geoscience." "I believe that rare earth resources undersea are much more promising than on-land resources," said Kato. "HP Pavilion DV4-1047TX Battery

oncentrations of rare earths were comparable to those found in clays mined in China. Some deposits contained twice as much heavy rare earths such as dysprosium, a component of magnets in hybrid car motors."[8]

Global rare earth production

Until 1948, most of the world's rare earths were sourced from placer sand deposits in India and Brazil.HP Pavilion DV4-1048TX Battery

Through the 1950s, South Africa took the status as the world's rare earth source, after large veins of rare earth bearing monazitewere discovered there.[9] Through the 1960s until the 1980s, the Mountain Pass rare earth mine in California was the leading producer.HP Pavilion DV4-1049TX Battery

Today, the Indian and South African deposits still produce some rare earth concentrates, but they are dwarfed by the scale of Chinese production. China now produces over 97% of the world's rare earth supply, mostly in Inner Mongolia,[10][11] even though it has only 37% of proven reserves.HP Pavilion DV4-1050 Battery

All of the world's heavy rare earths (such as dysprosium) come from Chinese rare earth sources such as the polymetallic Bayan Obo deposit. In 2010, the USGS released a study which found that the United States had 13 million metric tons of rare earth elements.HP Pavilion DV4-1050EE Battery

New demand has recently strained supply, and there is growing concern that the world may soon face a shortage of the rare earths.[15] In several years from 2009 worldwide demand for rare earth elements is expected to exceed supply by 40,000 tonnes annually unless major new sources are developed.HP Pavilion DV4-1050EL Battery

These concerns have intensified due to the actions of China, the predominant supplier. Specifically, China has announced regulations on exports and a crackdown on smuggling. On September 1, 2009, China announced plans to reduce its export quota to 35,000 tons per year in 2010–2015, ostensibly to conserve scarce resources and protect the environment.HP Pavilion DV4-1050EP Battery

On October 19, 2010 China Daily, citing an unnamed Ministry of Commerce official, reported that China will "further reduce quotas for rare earth exports by 30 percent at most next year to protect the precious metals from over-exploitation". At the end of 2010 China announced that the first round of export quotas in 2011 for rare earths would be 14,446 tons which was a 35% decrease from the previous first round of quotas in 2010.HP Pavilion DV4-1050ER Battery

China announced further export quotas on 14 July 2011 for the second half of the year with total allocation at 30,184 tons with total production capped at 93,800 tonnes.[21] In September 2011 China announced the halt in production of three of its eight major rare earth mines, responsible for almost 40% of China's total rare earth production.HP Pavilion DV4-1050TX Battery

As a result of the increased demand and tightening restrictions on exports of the metals from China, some countries are stockpiling rare earth resources. Searches for alternative sources in Australia, Brazil, Canada, South Africa, Greenland, and the United States are ongoing.HP Pavilion DV4-1051 Battery

Mines in these countries were closed when China undercut world prices in the 1990s, and it will take a few years to restart production as there are many barriers to entry.[17] One example is theMountain Pass mine in California, which is projected to reopen in 2011.HP Pavilion DV4-1051TX Battery

Other significant sites under development outside of China include the Nolans Project in Central Australia, the remote Hoidas Lake project in northern Canada, and the Mount Weld project in Australia.The Hoidas Lake project has the potential to supply about 10% of the $1 billion of REE consumption that occurs in North America every year.HP Pavilion DV4-1052 Battery

Vietnam signed an agreement in October 2010 to supply Japan with rare earths[29] from its northwestern Lai Châu Province.

Also under consideration for mining are sites such as Thor Lake in the Northwest Territories, various locations in Vietnam, and a site in southeast Nebraskain the US, where Quantum Rare Earth Development, a Canadian company, is currently conducting test drilling and economic feasibility studies toward opening a niobium mine.HP Pavilion DV4-1052TX Battery

Additionally, a large deposit of rare earth minerals was recently discovered in Kvanefjeld in southern Greenland.[32] Pre-feasibility drilling at this site has confirmed significant quantities of black lujavrite, which contains about 1% rare earth oxides (REO).[HP Pavilion DV4-1053 Battery

In early 2011, Australian mining company, Lynas, was reported to be "hurrying to finish" a US$230 million rare earth refinery on the eastern coast of Malaysia's industrial port of Kuantan. The plant would refine "slightly radioactive" ore - Lanthanide concentrate from the Mount Weld mine in Australia. HP Pavilion DV4-1053TX Battery

The ore would be trucked to Fremantle and transported by container ship to Kuantan. However, the Malaysian authorities confirmed that as of October 2011, Lynas was not given any permit to import any rare earth ore into Malaysia. Within two years, Lynas was said to expect the refinery to be able to meet nearly a third of the world's demand for rare earth materials, not counting China."HP Pavilion DV4-1054TX Battery

The Kuantan development brought renewed attention to the Malaysian town of Bukit Merah in Perak, where a rare-earth mine operated by a Mitsubishi Chemical subsidiary, Asian Rare Earth, closed in 1992 and left continuing environmental and health concerns.HP Pavilion DV4-1055TX Battery

In mid-2011, after protests, Malaysian government restrictions on the Lynas plant were announced. At that time, citing subscription-only Dow Jones Newswire reports, a Barronsreport said the Lynas investment was $730 million, and the projected share of the global market it would fill put at "about a sixth.HP Pavilion DV4-1070 Battery

An independent review was initiated by Malaysian Government and UN and conducted by IAEA between 29 May and 3 June 2011 to address concerns of radioactive hazards. The IAEA team was not able to identify any non-compliance with international radiation safety standards.[HP Pavilion DV4-1070EE Battery]

Another recently developed source of rare earths is electronic waste and other wastes that have significant rare earth components. New advances in recycling technology have made extraction of rare earths from these materials more feasible, and recycling plants are currently operating in Japan, where there is an estimated 300,000 tons of rare earths stored in unused electronics.HP Pavilion DV4-1070EF Battery

Significant quantities of rare earth oxides are found in tailings accumulated from 50 years of uranium ore, shale and loparite mining at Sillamäe, Estonia.[39] Due to the rising prices of rare earths, extraction of these oxides has become economically viable. The country currently exports around 3,000 tonnes per year, representing around 2% of world production.HP Pavilion DV4-1070ER Battery

Nuclear reprocessing is another potential source of rare earth or any other elements. Nuclear fission of uranium or plutonium produces a full range of elements, including all their isotopes. However, due to the radioactivity of many of these isotopes, it is unlikely that extracting them from the mixture can be done safely and economically.HP Pavilion DV4-1070ES Battery

Environmental considerations

Mining, refining, and recycling of rare earths have serious environmental consequences if not properly managed. A particular hazard is mildly radioactive slurrytailings resulting from the common occurrence of thorium and uranium in rare earth element ores.HP Pavilion DV4-1080EI Battery

Additionally, toxic acids are required during the refining process. Improper handling of these substances can result in extensive environmental damage. In May 2010, China announced a major, five-month crackdown on illegal mining in order to protect the environment and its resources. HP Pavilion DV4-1080EO Battery

This campaign is expected to be concentrated in the South, where mines – commonly small, rural, and illegal operations – are particularly prone to releasing toxic wastes into the general water supply. However, even the major operation in Baotou, in Inner Mongolia, where much of the world's rare earth supply is refined, has caused major environmental damage.HP Pavilion DV4-1080ES Battery

The Bukit Merah mine in Malaysia has been the focus of a US$100 million cleanup which is proceeding in 2011. "Residents blamed a rare earth refinery for birth defects and eight leukemia cases within five years in a community of 11,000 — after many years with no leukemia cases." HP Pavilion DV4-1090EO Battery

Seven of the leukemia victims died. After having accomplished the hilltop entombment of 11,000 truckloads of radioactively contaminated material, the project is expected to entail in summer, 2011, the removal of "more than 80,000 steel barrels of radioactive waste to the hilltop repository." HP Pavilion DV4-1090ES Battery

One of Mitsubishi's contractors for the cleanup is GeoSyntec, an Atlanta-based firm. Osamu Shimizu, a director of Asian Rare Earth, "said the company might have sold a few bags of calcium phosphate fertilizer on a trial basis as it sought to market byproducts" in reply to a former resident of Bukit Merah who said, "The cows that ate the grass [grown with the fertilizer] all died."HP Pavilion DV4-1100 Battery

In May 2011, after the Fukushima Daiichi nuclear disaster, widespread protests took place in Kuantan over the Lynas refinery and radioactive waste from it. The ore to be processed has very low levels of thorium, and Lynas founder and chief executive Nicholas Curtis said "There is absolutely no risk to public health." HP Pavilion DV4-1100EA Battery

T. Jayabalan, a doctor who says he has been monitoring and treating patients affected by the Mitsubishi plant, "is wary of Lynas's assurances. The argument that low levels of thorium in the ore make it safer doesn't make sense, he says, because radiation exposure is cumulative."HP Pavilion DV4-1101 Battery

Construction of the facility has been halted until an independent United Nations IAEA panel investigation is completed, which is expected by the end of June 2011.[45] New restrictions were announced by the Malaysian government in late June.[

IAEA panel investigation is completed and no construction has been halted.HP Pavilio

n DV4-1101TU Battery

Lynas is on budget and on schedule to start producing 2011. The IAEA report has concluded in a report issued by the nuclear watchdog Thursday June 2011 said it did not find any instance of "any non-compliance with international radiation safety standards" in the project. HP Pavilion DV4-1101TX Battery

Geo-political considerations

China has officially cited resource depletion and environmental concerns as the reasons for a nationwide crackdown on its rare earth mineral production sector. However, non-environmental motives have also been imputed to China's rare earth policy.HP Pavilion DV4-1102 Battery

According to The Economist, "Slashing their exports of rare-earth metals...is all about moving Chinese manufacturers up the supply chain, so they can sell valuable finished goods to the world rather than lowly raw materials." One possible example is the division of General Motors which deals with miniaturized magnet research, which shut down its US office and moved its entire staff toChina in 2006.HP Pavilion DV4-1102TU Battery

(It should be noted that China's export quota only applies to the metal but not products made from these metals such as magnets.

It was reported, but officially denied, that China instituted an export ban on shipments of rare earth oxides (but not alloys) to Japan on 22 September 2010, in response to the detainment of a Chinese fishing boat captain by the Japanese Coast Guard.HP Pavilion DV4-1102TX Battery

On September 2, 2010, a few days before the fishing boat incident,The Economist reported that "China...in July announced the latest in a series of annual export reductions, this time by 40% to precisely 30,258 tonnes."

The United States Department of Energy in its 2010 Critical Materials Strategy report identified dysprosium as the element that was most critical in terms of import reliance.HP Pavilion DV4-1103TU Battery

A 2011 report issued by the U.S. Geological Survey and U.S. Department of the Interior, “China’s Rare-Earth Industry," outlines industry trends within China and examines national policies that may guide the future of the country's production. The report notes that China’s lead in the production of rare-earth minerals has accelerated over the past two decades.HP Pavilion DV4-1103TX Battery

In 1990, China accounted for only 27% of such minerals. In 2009, world production was 132,000 metric tons; China produced 129,000 of those tons. According to the report, recent patterns suggest that China will slow the export of such materials to the world: “Owing to the increase in domestic demand, the Government has gradually reduced the export quota during the past several years.”HP Pavilion DV4-1104TU Battery

In 2006, China allowed 47 domestic rare-earth producers and traders and 12 Sino-foreign rare-earth producers to export. Controls have since tightened annually; by 2011, only 22 domestic rare-earth producers and traders and 9 Sino-foreign rare-earth producers were authorized. HP Pavilion DV4-1104TX Battery

The government’s future policies will likely keep in place strict controls: “According to China’s draft rare-earth development plan, annual rare-earth production may be limited to between 130,000 and 140,000 [metric tons] during the period from 2009 to 2015.HP Pavilion DV4-1105EF Battery

The export quota for rare-earth products may be about 35,000 [metric tons] and the Government may allow 20 domestic rare-earth producers and traders to export rare earths.”

The United States Geological Survey is actively surveying southern Afghanistan for rare earth deposits under the protection of United States military forces. HP Pavilion DV4-1105EM Battery

Since 2009 the USGS has conducted remote sensing surveys as well as fieldwork to verify Soviet claims that volcanic rocks containing rare earth metals exist in Helmand province near the village of Khanneshin. The USGS study team has located a sizable area of rocks in the center of an extinct volcano containing light rare earth elements including cerium and neodymium.HP Pavilion DV4-1105TU Battery

It has mapped 1.3 million metric tons of desirable rock, or about 10 years of supply at current demand levels. The Pentagon has estimated its value at about $7.4 billion.

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