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76-553: The mine is thought to have been discovered in 1521 and was originally mined for its tin deposits. 464,000 tonnes of antimony were produced at the mine between 1892 and 1929. From 1949 to 1981, 172,000 tonnes of antimony were produced. In 1981 1,700 tonnes of ore was being mined each day which was between 2 and 3 percent pure antimony. In 1981, reserves at the Xikuangshan deposit amounted to 10,000,000 tonnes of ore that contained 2 to 3 percent antimony (200-300,000 tonnes of antimony), at

152-472: A pro-inflammatory cytokine response in pulmonary epithelial cells . Unlike uITO, they can also bring endotoxin to workers handling the wet process if in contact with endotoxin-containing liquids. This can be attributed to the fact that sITOs have larger diameter and smaller surface area, and that this change after the sintering process can cause cytotoxicity . Because of these issues, alternatives to ITO have been found. The etching water used in

228-475: A bar of tin can be bent by hand with little effort. When bent, the so-called " tin cry " can be heard as a result of twinning in tin crystals. Tin is a post-transition metal in group 14 of the periodic table of elements. It is obtained chiefly from the mineral cassiterite , which contains stannic oxide , SnO 2 . Tin shows a chemical similarity to both of its neighbors in group 14, germanium and lead , and has two main oxidation states , +2 and

304-416: A cell culture substrate can be extended easily, which opens up new opportunities for studies on growing cells involving electron microscopy and correlative light. ITO can be used in nanotechnology to provide a path to a new generation of solar cells. Solar cells made with these devices have the potential to provide low-cost, ultra-lightweight, and flexible cells with a wide range of applications. Because of

380-419: A compromise must be made between conductivity and transparency, since increasing the thickness and increasing the concentration of charge carriers increases the film's conductivity, but decreases its transparency. Thin films of indium tin oxide are most commonly deposited on surfaces by physical vapor deposition . Often used is electron beam evaporation , or a range of sputter deposition techniques. ITO

456-651: A concentration of 5% uITO resulted in lymphocyte proliferation in mice including the number increase of cells through a 10-day period. A new occupational problem called indium lung disease was developed through contact with indium-containing dusts. The first patient is a worker associated with wet surface grinding of ITO who suffered from interstitial pneumonia : his lung was filled with ITO related particles. These particles can also induce cytokine production and macrophage dysfunction. Sintered ITOs particles alone can cause phagocytic dysfunction but not cytokine release in macrophage cells; however, they can intrigue

532-532: A major "tin crisis" ensued—tin was delisted from trading on the London Metal Exchange for about three years. ITC dissolved soon afterward, and the price of tin, now in a free-market environment, fell to $ 4 per pound and remained around that level through the 1990s. The price increased again by 2010 with a rebound in consumption following the 2007–2008 economic crisis , accompanying restocking and continued growth in consumption. London Metal Exchange (LME)

608-428: A method of light management in thin-film nanodisc-patterned hydrogenated amorphous silicon (a-Si:H) solar photovoltaic (PV) cells. A problem that arises for plasmonic-enhanced PV devices is the requirement for 'ultra-thin' transparent conducting oxides (TCOs) with high transmittance and low enough resistivity to be used as device top contacts/electrodes. Unfortunately, most work on TCOs is on relatively thick layers and

684-403: A more diverse range of possible substrates. A continuous conductive In-Sn alloy film is formed firstly, followed by oxidation to bring transparency. This two step process involves thermal annealing, which requires special atmosphere control and increased processing time. Because metal nanoparticles can be converted easily into a conductive metal film under the treatment of laser, laser sintering

760-526: A phenomenon known as " tin pest " or "tin disease". Some unverifiable sources also say that, during Napoleon 's Russian campaign of 1812, the temperatures became so cold that the tin buttons on the soldiers' uniforms disintegrated over time, contributing to the defeat of the Grande Armée , a persistent legend. The α-β transformation temperature is 13.2 °C (55.8 °F), but impurities (e.g. Al, Zn, etc.) lower it well below 0 °C (32 °F). With

836-636: A prospective replacement. As another carbon-based alternative, films of graphene are flexible and have been shown to allow 90% transparency with a lower electrical resistance than standard ITO. Thin metal films are also seen as a potential replacement material. A hybrid material alternative currently being tested is an electrode made of silver nanowires and covered with graphene . The advantages to such materials include maintaining transparency while simultaneously being electrically conductive and flexible. Inherently conductive polymers (ICPs) are also being developed for some ITO applications. Typically

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912-400: A significant reduction in the amount of semiconductor material needed compared to a conventional cell. Recent studies demonstrated that nanostructured ITO can behave as a miniaturized photocapacitor, combining in a unique material the absorption and storage of light energy. Inhalation of indium tin oxide may cause mild irritation to the respiratory tracts and should be avoided. If exposure

988-552: A solution with most metals and elements so tin does not have much solid solubility. Tin mixes well with bismuth , gallium , lead , thallium and zinc , forming simple eutectic systems. Tin becomes a superconductor below 3.72  K and was one of the first superconductors to be studied. The Meissner effect , one of the characteristic features of superconductors, was first discovered in superconducting tin crystals. Tin resists corrosion from water , but can be corroded by acids and alkalis . Tin can be highly polished and

1064-576: A team from the Chinese Academy of Sciences , Indiana University Bloomington and the University of Alberta . 27°45′07″N 111°28′59″E  /  27.752°N 111.483°E  / 27.752; 111.483 Tin Tin is a chemical element ; it has symbol Sn (from Latin stannum ) and atomic number 50. A silvery-colored metal, tin is soft enough to be cut with little force, and

1140-617: A thin film can have an optical transmittance of greater than 80%. These properties are utilized to great advantage in touch-screen applications such as mobile phones . Indium tin oxide (ITO) is an optoelectronic material that is applied widely in both research and industry. ITO can be used for many applications, such as flat-panel displays, smart windows, polymer-based electronics, thin film photovoltaics, glass doors of supermarket freezers, and architectural windows. Moreover, ITO thin films for glass substrates can be helpful for glass windows to conserve energy. ITO green tapes are utilized for

1216-608: A tin or tin-lead coolant, the tin would first have to go through isotopic separation to remove the isotopes with odd mass number. Combined, these three isotopes make up about 17% of natural tin but represent nearly all of the capture cross section. Of the remaining seven isotopes tin-112 has a capture cross section of 1 barn. The other six isotopes forming 82.7% of natural tin have capture cross sections of 0.3 barns or less, making them effectively transparent to neutrons. Tin has 31 unstable isotopes, ranging in mass number from 99 to 139. The unstable tin isotopes have half-lives of less than

1292-448: A year except for tin-126 , which has a half-life of about 230,000 years. Tin-100 and tin-132 are two of the very few nuclides with a " doubly magic " nucleus which despite being unstable, as they have very uneven neutron–proton ratios , are the endpoints beyond which tin isotopes lighter than tin-100 and heavier than tin-132 are much less stable. Another 30 metastable isomers have been identified for tin isotopes between 111 and 131,

1368-437: Is a mixed oxide of indium and tin with a melting point in the range 1526–1926 °C (1800–2200 K , 2800–3500 °F), depending on composition. The most commonly used material is an oxide of a composition of ca. In 4 Sn. The material is a n-type semiconductor with a large bandgap of around 4 eV. ITO is both transparent to visible light and relatively conductive. It has a low electrical resistivity of ~10 Ω ·cm, and

1444-484: Is also used for various optical coatings , most notably infrared -reflecting coatings ( hot mirrors ) for automotive, and sodium vapor lamp glasses. Other uses include gas sensors , antireflection coatings , electrowetting on dielectrics, and Bragg reflectors for VCSEL lasers. ITO is also used as the IR reflector for low-e window panes. ITO was also used as a sensor coating in the later Kodak DCS cameras, starting with

1520-442: Is applied to achieve products' homogeneous morphology. Laser sintering is also easy and less costly to use since it can be performed in air. For example, using conventional methods but varying the ambient gas conditions to improve the optoelectronic properties as, for example, oxygen plays a major role in the properties of ITO. There has been numerical modeling of plasmonic metallic nanostructures have shown great potential as

1596-488: Is disrupted by the difference in the ratio of oxygen to metal atoms between In 2 O 3 and ZnO. Indium-zinc-oxide has some comparable properties to ITO. The amorphous structure remains stable even up to 500 °C, which allows for important processing steps common in organic solar cells . The improvement in homogeneity significantly enhances the usability of the material in the case of organic solar cells . Areas of poor electrode performance in organic solar cells render

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1672-467: Is evidence that Cornwall in the first centuries AD was the main source of tin. Tin extraction and use can be dated to the beginnings of the Bronze Age around 3000 BC, when it was observed that copper objects formed of polymetallic ores with different metal contents had different physical properties. The earliest bronze objects had a tin or arsenic content of less than 2% and are believed to be

1748-563: Is generated via the long s -process in low-to-medium mass stars (with masses of 0.6 to 10 times that of the Sun ), and finally by beta decay of the heavy isotopes of indium . Tin is the 49th most abundant element in Earth's crust , representing 2  ppm compared with 75 ppm for zinc, 50 ppm for copper, and 14 ppm for lead. Tin does not occur as the native element but must be extracted from various ores. Cassiterite ( SnO 2 )

1824-461: Is long-term, symptoms may become chronic and result in benign pneumoconiosis . Studies with animals indicate that indium tin oxide is toxic when ingested, along with negative effects on the kidney, lung, and heart. During the process of mining, production and reclamation, workers are potentially exposed to indium, especially in countries such as China, Japan, the Republic of Korea, and Canada and face

1900-471: Is quite small. Therefore, the cost penalty per cell is quite small, too. The primary advantage of ITO compared to AZO as a transparent conductor for LCDs is that ITO can be precisely etched into fine patterns. AZO cannot be etched as precisely: It is so sensitive to acid that it tends to get over-etched by an acid treatment. Another benefit of ITO compared to AZO is that if moisture does penetrate, ITO will degrade less than AZO. The role of ITO glass as

1976-528: Is the least common stable isotope. The isotopes with even mass numbers have no nuclear spin , while those with odd mass numbers have a nuclear spin of 1/2. It is thought that tin has such a great multitude of stable isotopes because of tin's atomic number being 50, which is a " magic number " in nuclear physics. Tin is one of the easiest elements to detect and analyze by NMR spectroscopy , which relies on molecular weight and its chemical shifts are referenced against tetramethyltin ( SnMe 4 ). Of

2052-590: Is the nonmetallic form. It is stable below 13.2 °C (55.8 °F) and is brittle . α-tin has a diamond cubic crystal structure, as do diamond and silicon . α-tin does not have metallic properties because its atoms form a covalent structure in which electrons cannot move freely. α-tin is a dull-gray powdery material with no common uses other than specialized semiconductor applications. γ-tin and σ-tin exist at temperatures above 161 °C (322 °F)  and pressures above several GPa . In cold conditions β-tin tends to transform spontaneously into α-tin,

2128-443: Is the only commercially important source of tin, although small quantities of tin are recovered from complex sulfides such as stannite , cylindrite , franckeite , canfieldite , and teallite . Minerals with tin are almost always associated with granite rock, usually at a level of 1% tin oxide content. Because of the higher specific gravity of tin dioxide, about 80% of mined tin is from secondary deposits found downstream from

2204-628: Is tin's principal trading site. Other tin contract markets are Kuala Lumpur Tin Market (KLTM) and Indonesia Tin Exchange (INATIN). Due to factors involved in the 2021 global supply chain crisis , tin prices almost doubled during 2020–21 and have had their largest annual rise in over 30 years. Global refined tin consumption dropped 1.6 percent in 2020 as the COVID-19 pandemic disrupted global manufacturing industries. In 2018, just under half of all tin produced

2280-472: Is transparent and colorless in thin layers, while in bulk form it is yellowish to gray. In the infrared region of the spectrum it acts as a metal-like mirror. Indium tin oxide is one of the most widely used transparent conducting oxides , not just for its electrical conductivity and optical transparency , but also for the ease with which it can be deposited as a thin film, as well as its chemical resistance to moisture. As with all transparent conducting films,

2356-425: Is used as a protective coat for other metals. When heated in air it oxidizes slowly to form a thin passivation layer of stannic oxide ( SnO 2 ) that inhibits further oxidation. Tin has ten stable isotopes , the greatest number of any element. Their mass numbers are 112, 114, 115, 116, 117, 118, 119, 120, 122, and 124. Tin-120 makes up almost a third of all tin. Tin-118 and tin-116 are also common. Tin-115

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2432-405: Is used as the anode (hole injection layer). ITO films deposited on windshields are used for defrosting aircraft windshields. The heat is generated by applying a voltage across the film. ITO is also used to reflect electromagnetic radiation . The F-22 Raptor 's canopy has an ITO coating that reflects radar waves, enhancing its stealth capabilities and giving it a distinctive gold tint. ITO

2508-444: Is widely used for food packaging as " tin cans ". Some organotin compounds can be extremely toxic. Tin is a soft, malleable , ductile and highly crystalline silvery-white metal . When a bar of tin is bent a crackling sound known as the " tin cry " can be heard from the twinning of the crystals. This trait is shared by indium , cadmium , zinc , and mercury in its solid state. Tin melts at about 232 °C (450 °F),

2584-505: The r -process (rapid neutron capture) in supernovae and neutron star mergers . Tin isotopes 115, 117 through 120, and 122 are produced via both the s -process and the r -process, The two lightest stable isotopes, tin-112 and tin-114, cannot be made in significant amounts in the s - or r -processes and are among the p-nuclei whose origins are not well understood. Some theories about their formation include proton capture and photodisintegration . Tin-115 might be partially produced in

2660-454: The Bronze Age . In modern times, tin is used in many alloys, most notably tin-lead soft solders , which are typically 60% or more tin, and in the manufacture of transparent, electrically conducting films of indium tin oxide in optoelectronic applications. Another large application is corrosion -resistant tin plating of steel . Because of the low toxicity of inorganic tin, tin-plated steel

2736-508: The diamond cubic structure. Metallic tin does not easily oxidize in air and water. The first tin alloy used on a large scale was bronze , made of 1 ⁄ 8  tin and 7 ⁄ 8   copper (12.5% and 87.5% respectively), from as early as 3000 BC. After 600 BC, pure metallic tin was produced. Pewter , which is an alloy of 85–90% tin with the remainder commonly consisting of copper , antimony , bismuth, and sometimes lead and silver, has been used for flatware since

2812-608: The s -process, both directly and as the daughter of long-lived indium-115 , and also from the decay of indium-115 produced via the r -process. The word tin is shared among Germanic languages and can be traced back to reconstructed Proto-Germanic * tin-om ; cognates include German Zinn , Swedish tenn and Dutch tin . It is not found in other branches of Indo-European , except by borrowing from Germanic (e.g., Irish tinne from English). The Latin name for tin, stannum , originally meant an alloy of silver and lead, and came to mean 'tin' in

2888-531: The AgNPs and a matrix of the other orientation. The domains are stronger than the matrix and function as barriers to crack propagation, significantly increasing the flexibility. The change in resistivity with increased bending significantly decreases in the hybrid ITO compared with homogeneous ITO. ITO is typically deposited through expensive and energy-intensive processes that deal with physical vapor deposition (PVD). Such processes include sputtering , which results in

2964-516: The Kodak DCS 520, as a means of increasing blue channel response. ITO thin film strain gauges can operate at temperatures up to 1400 °C and can be used in harsh environments, such as gas turbines , jet engines , and rocket engines . ITO has been popularly used as a high-quality flexible substrate to produce flexible electronics. However, this substrate's flexibility decreases as its conductivity improves. Previous research have indicated that

3040-459: The Near East where arsenic is commonly found with copper ore, but the health risks were quickly realized and the quest for sources of the much less hazardous tin ores began early in the Bronze Age. This created the demand for rare tin metal and formed a trade network that linked the distant sources of tin to the markets of Bronze Age cultures. Cassiterite ( SnO 2 ), the oxide form of tin,

3116-637: The United States has neither mined (since 1993) nor smelted (since 1989) tin, it was the largest secondary producer, recycling nearly 14,000 tonnes in 2006. New deposits are reported in Mongolia , and in 2009, new deposits of tin were discovered in Colombia. Tin is produced by carbothermic reduction of the oxide ore with carbon or coke. Both reverberatory furnace and electric furnace can be used: The ten largest tin-producing companies produced most of

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3192-496: The addition of antimony or bismuth the transformation might not occur at all, increasing durability. Commercial grades of tin (99.8% tin content) resist transformation because of the inhibiting effect of small amounts of bismuth, antimony, lead, and silver present as impurities. Alloying elements such as copper, antimony, bismuth, cadmium, and silver increase the hardness of tin. Tin easily forms hard, brittle intermetallic phases that are typically undesirable. It does not mix into

3268-507: The arts to stain porcelain . Indium tin oxide Indium tin oxide ( ITO ) is a ternary composition of indium , tin and oxygen in varying proportions. Depending on the oxygen content, it can be described as either a ceramic or an alloy . Indium tin oxide is typically encountered as an oxygen-saturated composition with a formulation of 74% In, 8% Sn, and 18% O by weight. Oxygen-saturated compositions are so typical that unsaturated compositions are termed oxygen-deficient ITO . It

3344-588: The complex agreements between producer countries and consumer countries dating back to 1921. Earlier agreements tended to be somewhat informal and led to the "First International Tin Agreement" in 1956, the first of a series that effectively collapsed in 1985. Through these agreements, the International Tin Council (ITC) had a considerable effect on tin prices. ITC supported the price of tin during periods of low prices by buying tin for its buffer stockpile and

3420-497: The conductivity is lower for conducting polymers, such as polyaniline and PEDOT :PSS, than for inorganic materials, but they are more flexible, less expensive and more environmentally friendly in processing and manufacture. In order to reduce indium content, decrease processing difficulty, and improve electrical homogeneity, amorphous transparent conducting oxides have been developed. One such material, amorphous indium-zinc-oxide maintains short-range order even though crystallization

3496-686: The costly layer deposition requiring vacuum, alternative materials are being investigated. Promising alternatives based on zinc oxide doped with various elements. Promising alternatives based on zinc oxide doped with various elements. Several transition metal dopants in indium oxide, particularly molybdenum, give much higher electron mobility and conductivity than obtained with tin. Doped binary compounds such as aluminum-doped zinc oxide (AZO) and indium-doped cadmium oxide have been proposed as alternative materials. Other inorganic alternatives include aluminum , gallium or indium-doped zinc oxide (AZO, GZO or IZO). Carbon nanotube conductive coatings are

3572-526: The few reported cases of thin TCO showed a marked decrease in conductivity. To overcome this it is possible to first grow a thick layer and then chemically shave it down to obtain a thin layer that is whole and highly conductive. A major concern with ITO is its cost. ITO costs several times more than aluminium zinc oxide (AZO). AZO is a common choice of transparent conducting oxide (TCO) because of its lower cost and relatively good optical transmission performance in

3648-614: The formation of brittle layers. Because of the cost and energy of physical vapor deposition, with the required vacuum processing, alternative methods of preparing ITO are being investigated. An alternative process that uses a particle-based technique, is known as the tape casting process. Because it is a particle-based technique, the ITO nano-particles are dispersed first, then placed in organic solvents for stability. Benzyl phthalate plasticizer and polyvinyl butyral binder have been shown to be helpful in preparing nanoparticle slurries . Once

3724-586: The fourth century —the earlier Latin word for it was plumbum candidum , or "white lead". Stannum apparently came from an earlier stāgnum (meaning the same substance), the origin of the Romance and Celtic terms for tin , such as French étain , Spanish estaño , Italian stagno , and Irish stán . The origin of stannum / stāgnum is unknown; it may be pre- Indo-European . The Meyers Konversations-Lexikon suggests instead that stannum came from Cornish stean , and

3800-439: The great majority of its compounds, tin has the oxidation state II or IV. Compounds containing bivalent tin are called stannous while those containing tetravalent tin are termed stannic . Halide compounds are known for both oxidation states. For Sn(IV), all four halides are well known: SnF 4 , SnCl 4 , SnBr 4 , and SnI 4 . The three heavier members are volatile molecular compounds, whereas

3876-451: The late 1970s and early 1980s, the U.S. reduced its strategic tin stockpile, partly to take advantage of historically high tin prices. The 1981–82 recession damaged the tin industry. Tin consumption declined dramatically. ITC was able to avoid truly steep declines through accelerated buying for its buffer stockpile; this activity required extensive borrowing. ITC continued to borrow until late 1985 when it reached its credit limit. Immediately,

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3952-460: The lowest in group 14, and boils at 2,602 °C (4,716 °F), the second lowest (ahead of lead ) in its group. The melting point is further lowered to 177.3 °C (351.1 °F) for 11 nm particles. β-tin, also called white tin , is the allotrope (structural form) of elemental tin that is stable at and above room temperature. It is metallic and malleable, and has body-centered tetragonal crystal structure. α-tin, or gray tin ,

4028-451: The market and mining technology. It is estimated that, at current consumption rates and technologies, the Earth will run out of mine-able tin in 40 years. In 2006 Lester Brown suggested tin could run out within 20 years based on conservative estimates of 2% annual growth. Scrap tin is an important source of the metal. Recovery of tin through recycling is increasing rapidly as of 2019. Whereas

4104-436: The mechanical properties of ITO can be improved through increasing the degree of crystallinity . Doping with silver (Ag) can improve this property, but results in a loss of transparency. An improved method that embeds Ag nanoparticles (AgNPs) instead of homogeneously to create a hybrid ITO has proven to be effective in compensating for the decrease in transparency. The hybrid ITO consists of domains in one orientation grown on

4180-412: The most stable being tin-121m, with a half-life of 43.9 years. The relative differences in the abundances of tin's stable isotopes can be explained by how they are formed during stellar nucleosynthesis . Tin-116 through tin-120, along with tin-122, are formed in the s -process (slow neutron capture) in most stars which leads to them being the most common tin isotopes, while tin-124 is only formed in

4256-409: The nanoscale dimensions of the nanorods, quantum-size effects influence their optical properties. By tailoring the size of the rods, they can be made to absorb light within a specific narrow band of colors. By stacking several cells with different sized rods, a broad range of wavelengths across the solar spectrum can be collected and converted to energy. Moreover, the nanoscale volume of the rods leads to

4332-518: The possibility of pulmonary alveolar proteinosis , pulmonary fibrosis , emphysema , and granulomas . Workers in the US, China, and Japan have been diagnosed with cholesterol clefts under indium exposure. Silver nanoparticles existed in improved ITOs have been found in vitro to penetrate through both intact and breached skin into the epidermal layer . Un-sintered ITOs are suspected of induce T-cell -mediated sensitization: on an intradermal exposure study,

4408-609: The primary lodes. Tin is often recovered from granules washed downstream in the past and deposited in valleys or the sea. The most economical ways of mining tin are by dredging , hydraulicking , or open pits . Most of the world's tin is produced from placer deposits, which can contain as little as 0.015% tin. About 253,000 tonnes of tin were mined in 2011, mostly in China (110,000 t), Indonesia (51,000 t), Peru (34,600 t), Bolivia (20,700 t) and Brazil (12,000 t). Estimates of tin production have historically varied with

4484-422: The process of sintering ITO can only be used for a limited numbers of times before it has to be disposed. After degradation, the waste water should still contain valuable metals such as In and Cu as a secondary resource as well as Mo, Cu, Al, Sn and In, which can pose a health hazard to human beings. Because of high cost and limited supply of indium, the fragility and lack of flexibility of ITO layers, and

4560-666: The production of lamps that are electroluminescent, functional, and fully flexible. Also, ITO thin films are used primarily to serve as coatings that are anti-reflective and for liquid crystal displays (LCDs) and electroluminescence, where the thin films are used as conducting, transparent electrodes. ITO is often used to make transparent conductive coating for displays such as liquid crystal displays , OLED displays, plasma displays , touch panels , and electronic ink applications. Thin films of ITO are also used in organic light-emitting diodes , solar cells , antistatic coatings and EMI shieldings. In organic light-emitting diodes , ITO

4636-472: The reaction of hydrochloric acid and tin produces SnCl 2 and hydrogen gas. Alternatively SnCl 4 and Sn combine to stannous chloride by a process called comproportionation : Tin can form many oxides, sulfides, and other chalcogenide derivatives. The dioxide SnO 2 (cassiterite) forms when tin is heated in the presence of air . SnO 2 is amphoteric , which means that it dissolves in both acidic and basic solutions. Stannates with

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4712-456: The result of unintentional alloying due to trace metal content in the copper ore. The addition of a second metal to copper increases its hardness, lowers the melting temperature, and improves the casting process by producing a more fluid melt that cools to a denser, less spongy metal. This was an important innovation that allowed for the much more complex shapes cast in closed molds of the Bronze Age. Arsenical bronze objects appear first in

4788-427: The slightly more stable +4. Tin is the 49th most abundant element on Earth, making up 0.00022% of its crust, and with 10 stable isotopes, it has the largest number of stable isotopes in the periodic table, due to its magic number of protons. It has two main allotropes : at room temperature, the stable allotrope is β-tin, a silvery-white, malleable metal; at low temperatures it is less dense grey α-tin, which has

4864-441: The solar spectrum. However, ITO is superior to AZO in many other important performance categories including chemical resistance to moisture. ITO is not affected by moisture, and is stable as part of copper indium gallium selenide solar cell for 25–30 years on a rooftop. While the sputtering target or evaporative material that is used to deposit the ITO is significantly more costly than AZO, the amount of material placed on each cell

4940-586: The stable isotopes, tin-115 has a high neutron capture cross section for fast neutrons, at 30 barns . Tin-117 has a cross section of 2.3 barns, one order of magnitude smaller, while tin-119 has a slightly smaller cross section of 2.2 barns. Before these cross sections were well known, it was proposed to use tin-lead solder as a coolant for fast reactors because of its low melting point. Current studies are for lead or lead-bismuth reactor coolants because both heavy metals are nearly transparent to fast neutrons, with very low capture cross sections. In order to use

5016-678: The structure [ Sn(OH) 6 ] , like K 2 [ Sn(OH) 6 ], are also known, though the free stannic acid H 2 [ Sn(OH) 6 ] is unknown. Sulfides of tin exist in both the +2 and +4 oxidation states: tin(II) sulfide and tin(IV) sulfide ( mosaic gold ). Stannane ( SnH 4 ), with tin in the +4 oxidation state, is unstable. Organotin hydrides are however well known, e.g. tributyltin hydride (Sn(C 4 H 9 ) 3 H). These compounds release transient tributyl tin radicals, which are rare examples of compounds of tin(III). Organotin compounds, sometimes called stannanes, are chemical compounds with tin–carbon bonds. Of

5092-410: The tape casting process has been carried out, the characterization of the green ITO tapes showed that optimal transmission went up to about 75%, with a lower bound on the electrical resistance of 2 Ω·cm. Using ITO nanoparticles imposes a limit on the choice of substrate, owing to the high temperature required for sintering . As an alternative starting material, In-Sn alloy nanoparticles allow for

5168-420: The tetrafluoride is polymeric. All four halides are known for Sn(II) also: SnF 2 , SnCl 2 , SnBr 2 , and SnI 2 . All are polymeric solids. Of these eight compounds, only the iodides are colored. Tin(II) chloride (also known as stannous chloride) is the most important commercial tin halide. Illustrating the routes to such compounds, chlorine reacts with tin metal to give SnCl 4 whereas

5244-523: The tetraorgano derivatives, are prepared by redistribution reactions : Divalent organotin compounds are uncommon, although more common than related divalent organogermanium and organosilicon compounds. The greater stabilization enjoyed by Sn(II) is attributed to the " inert pair effect ". Organotin(II) compounds include both stannylenes (formula: R 2 Sn, as seen for singlet carbenes ) and distannylenes (R 4 Sn 2 ), which are roughly equivalent to alkenes . Both classes exhibit unusual reactions. Tin

5320-405: The time geologists thought that there may be more in the area. By 2002 the estimated size of the deposit was 2,110,000 tonnes of pure antimony. The ore is composed of quartz , calcite , stibnite and some pyrite . Using samarium–neodymium dating , it has been estimated that the deposit formed during the late Jurassic – early Cretaceous period (around 145 million years ago). In April 2010 it

5396-588: The tin compounds, the organic derivatives are commercially the most useful. Some organotin compounds are highly toxic and have been used as biocides . The first organotin compound to be reported was diethyltin diiodide ((C 2 H 5 ) 2 SnI 2 ), reported by Edward Frankland in 1849. Most organotin compounds are colorless liquids or solids that are stable to air and water. They adopt tetrahedral geometry. Tetraalkyl- and tetraaryltin compounds can be prepared using Grignard reagents : The mixed halide-alkyls, which are more common and more important commercially than

5472-586: The world's tin in 2007. Most of the world's tin is traded on LME, from 8 countries, under 17 brands. The International Tin Council was established in 1947 to control the price of tin. It collapsed in 1985. In 1984, the Association of Tin Producing Countries was created, with Australia, Bolivia, Indonesia, Malaysia, Nigeria, Thailand, and Zaire as members. Tin is unique among mineral commodities because of

5548-458: Was able to restrain the price during periods of high prices by selling from the stockpile. This was an anti-free-market approach, designed to assure a sufficient flow of tin to consumer countries and a profit for producer countries. However, the buffer stockpile was not sufficiently large, and during most of those 29 years tin prices rose, sometimes sharply, especially from 1973 through 1980 when rampant inflation plagued many world economies. During

5624-549: Was most likely the original source of tin. Other tin ores are less common sulfides such as stannite that require a more involved smelting process. Cassiterite often accumulates in alluvial channels as placer deposits because it is harder, heavier, and more chemically resistant than the accompanying granite . Cassiterite is usually black or dark in color, and these deposits can be easily seen in river banks . Alluvial ( placer ) deposits may incidentally have been collected and separated by methods similar to gold panning . In

5700-438: Was reported that antimony levels in water near the mine were as high as 11 parts per million, a thousand times those found in uncontaminated water. The antimony was found to be in the V oxidation state, believed to be the least dangerous aqueous form (antimony can have a I, III or V oxidation state ). The environmental effects of this high level of the rare metalloid are poorly understood and are currently under investigation by

5776-415: Was used in solder. The rest was divided between tin plating, tin chemicals, brass and bronze alloys, and niche uses. Pigment Yellow 38, tin(IV) sulfide , is known as mosaic gold . Purple of Cassius , Pigment Red 109, a hydrous double stannate of gold , was mainly, in terms of painting, restricted to miniatures due to its high cost. It was widely used to make cranberry glass . It has also been used in

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