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95-480: Pyrkakay represented one of the largest tin reserves in Russia having estimated reserves of 228.5 million tonnes of ore grading 0.23% tin . The Krasnoarmeysky settlement, built to house the miners, was determined to no longer be economically viable in 1998 and is now a ghost town . This Chukotka Autonomous Okrug location article is a stub . You can help Misplaced Pages by expanding it . This article about

190-409: A condenser . Some alchemists called this zinc oxide lana philosophica , Latin for "philosopher's wool", because it collected in wooly tufts, whereas others thought it looked like white snow and named it nix album . The name of the metal was probably first documented by Paracelsus , a Swiss-born German alchemist, who referred to the metal as "zincum" or "zinken" in his book Liber Mineralium II , in

285-428: A gamma ray . Zn has three excited metastable states and Zn has two. The isotopes Zn , Zn , Zn and Zn each have only one excited metastable state. The most common decay mode of a radioisotope of zinc with a mass number lower than 66 is electron capture . The decay product resulting from electron capture is an isotope of copper. The most common decay mode of

380-518: A by-product of smelting sulfide ores. Zinc in such remnants in smelting ovens was usually discarded as it was thought to be worthless. The manufacture of brass was known to the Romans by about 30 BC. They made brass by heating powdered calamine (zinc silicate or carbonate), charcoal and copper together in a crucible. The resulting calamine brass was then either cast or hammered into shape for use in weaponry. Some coins struck by Romans in

475-560: A deficit of zinc can compromise the vitality of primary algal communities, potentially destabilizing the intricate marine trophic structures and consequently impacting biodiversity. Brass , an alloy of copper and zinc in various proportions, was used as early as the third millennium BC in the Aegean area and the region which currently includes Iraq , the United Arab Emirates , Kalmykia , Turkmenistan and Georgia . In

570-400: A half-life of 243.66 days, is the least active radioisotope, followed by Zn with a half-life of 46.5 hours. Zinc has 10 nuclear isomers , of which Zn has the longest half-life, 13.76 h. The superscript m indicates a metastable isotope. The nucleus of a metastable isotope is in an excited state and will return to the ground state by emitting a photon in the form of

665-541: 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)

760-515: A metal which, when oxidized, produces pushpanjan , thought to be zinc oxide. Zinc mines at Zawar, near Udaipur in India, have been active since the Mauryan period ( c.  322 and 187 BCE). The smelting of metallic zinc here, however, appears to have begun around the 12th century AD. One estimate is that this location produced an estimated million tonnes of metallic zinc and zinc oxide from

855-417: A metal–carbon sigma bond . Cobalticyanide paper (Rinnmann's test for Zn) can be used as a chemical indicator for zinc. 4 g of K 3 Co(CN) 6 and 1 g of KClO 3 is dissolved on 100 ml of water. Paper is dipped in the solution and dried at 100 °C. One drop of the sample is dropped onto the dry paper and heated. A green disc indicates the presence of zinc. Various isolated examples of

950-532: 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

1045-510: A process in 1758 for calcining zinc sulfide into an oxide usable in the retort process. Prior to this, only calamine could be used to produce zinc. In 1798, Johann Christian Ruberg improved on the smelting process by building the first horizontal retort smelter. Jean-Jacques Daniel Dony built a different kind of horizontal zinc smelter in Belgium that processed even more zinc. Italian doctor Luigi Galvani discovered in 1780 that connecting

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1140-596: A quantity of what he called "calay" (from the Malay or Hindi word for tin) originating from Malabar off a cargo ship captured from the Portuguese in the year 1596. Libavius described the properties of the sample, which may have been zinc. Zinc was regularly imported to Europe from the Orient in the 17th and early 18th centuries, but was at times very expensive. Metallic zinc was isolated in India by 1300 AD. Before it

1235-401: A radioisotope of zinc with mass number higher than 66 is beta decay (β ), which produces an isotope of gallium . Zinc has an electron configuration of [Ar]3d 4s and is a member of the group 12 of the periodic table . It is a moderately reactive metal and strong reducing agent . The surface of the pure metal tarnishes quickly, eventually forming a protective passivating layer of

1330-552: 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

1425-474: A specific mine is a stub . You can help Misplaced Pages by expanding it . 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 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

1520-608: 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

1615-448: 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,

1710-403: Is a chalcophile , meaning the element is more likely to be found in minerals together with sulfur and other heavy chalcogens , rather than with the light chalcogen oxygen or with non-chalcogen electronegative elements such as the halogens . Sulfides formed as the crust solidified under the reducing conditions of the early Earth's atmosphere. Sphalerite , which is a form of zinc sulfide,

1805-470: 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 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

1900-407: 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), the lowest in group 14, and boils at 2,602 °C (4,716 °F),

1995-444: Is an essential trace element for humans, animals, plants and for microorganisms and is necessary for prenatal and postnatal development. It is the second most abundant trace metal in humans after iron and it is the only metal which appears in all enzyme classes . Zinc is also an essential nutrient element for coral growth as it is an important cofactor for many enzymes. Zinc deficiency affects about two billion people in

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2090-546: Is being smelted. In Britain, John Lane is said to have carried out experiments to smelt zinc, probably at Landore , prior to his bankruptcy in 1726. In 1738 in Great Britain, William Champion patented a process to extract zinc from calamine in a vertical retort -style smelter. His technique resembled that used at Zawar zinc mines in Rajasthan , but no evidence suggests he visited the Orient. Champion's process

2185-473: 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

2280-570: 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 )

2375-527: Is hard and brittle at most temperatures but becomes malleable between 100 and 150 °C. Above 210 °C, the metal becomes brittle again and can be pulverized by beating. Zinc is a fair conductor of electricity . For a metal, zinc has relatively low melting (419.5 °C) and boiling point (907 °C). The melting point is the lowest of all the d-block metals aside from mercury and cadmium ; for this reason among others, zinc, cadmium, and mercury are often not considered to be transition metals like

2470-464: Is implicated by the formation of a yellow diamagnetic glass by dissolving metallic zinc in molten ZnCl 2 . The [Zn 2 ] core would be analogous to the [Hg 2 ] cation present in mercury (I) compounds. The diamagnetic nature of the ion confirms its dimeric structure. The first zinc(I) compound containing the Zn–Zn bond, (η -C 5 Me 5 ) 2 Zn 2 . Binary compounds of zinc are known for most of

2565-410: Is known as Special High Grade, often abbreviated SHG , and is 99.995% pure. Worldwide, 95% of new zinc is mined from sulfidic ore deposits, in which sphalerite (ZnS) is nearly always mixed with the sulfides of copper, lead and iron. Zinc mines are scattered throughout the world, with the main areas being China, Australia, and Peru. China produced 38% of the global zinc output in 2014. Zinc metal

2660-524: Is necessary for the leaching process. If deposits of zinc carbonate , zinc silicate , or zinc-spinel (like the Skorpion Deposit in Namibia ) are used for zinc production, the roasting can be omitted. For further processing two basic methods are used: pyrometallurgy or electrowinning . Pyrometallurgy reduces zinc oxide with carbon or carbon monoxide at 950 °C (1,740 °F) into

2755-437: Is produced using extractive metallurgy . The ore is finely ground, then put through froth flotation to separate minerals from gangue (on the property of hydrophobicity ), to get a zinc sulfide ore concentrate consisting of about 50% zinc, 32% sulfur, 13% iron, and 5% SiO 2 . Roasting converts the zinc sulfide concentrate to zinc oxide: The sulfur dioxide is used for the production of sulfuric acid, which

2850-562: 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,

2945-528: 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

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3040-589: Is the most heavily mined zinc-containing ore because its concentrate contains 60–62% zinc. Other source minerals for zinc include smithsonite (zinc carbonate ), hemimorphite (zinc silicate ), wurtzite (another zinc sulfide), and sometimes hydrozincite (basic zinc carbonate ). With the exception of wurtzite, all these other minerals were formed by weathering of the primordial zinc sulfides. Identified world zinc resources total about 1.9–2.8 billion tonnes . Large deposits are in Australia, Canada and

3135-443: 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

3230-642: 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

3325-425: 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

3420-473: 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 is widely used for food packaging as " tin cans ". Some organotin compounds can be extremely toxic. Tin

3515-505: 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

3610-469: The metalloids and all the nonmetals except the noble gases . The oxide ZnO is a white powder that is nearly insoluble in neutral aqueous solutions, but is amphoteric , dissolving in both strong basic and acidic solutions. The other chalcogenides ( ZnS , ZnSe , and ZnTe ) have varied applications in electronics and optics. Pnictogenides ( Zn 3 N 2 , Zn 3 P 2 , Zn 3 As 2 and Zn 3 Sb 2 ),

3705-608: 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

3800-518: The spinal cord of a freshly dissected frog to an iron rail attached by a brass hook caused the frog's leg to twitch. He incorrectly thought he had discovered an ability of nerves and muscles to create electricity and called the effect " animal electricity ". The galvanic cell and the process of galvanization were both named for Luigi Galvani, and his discoveries paved the way for electrical batteries , galvanization, and cathodic protection . Galvani's friend, Alessandro Volta , continued researching

3895-403: The 12th to 16th centuries. Another estimate gives a total production of 60,000 tonnes of metallic zinc over this period. The Rasaratna Samuccaya , written in approximately the 13th century AD, mentions two types of zinc-containing ores: one used for metal extraction and another used for medicinal purposes. Zinc was distinctly recognized as a metal under the designation of Yasada or Jasada in

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3990-619: The 16th century. The word is probably derived from the German zinke , and supposedly meant "tooth-like, pointed or jagged" (metallic zinc crystals have a needle-like appearance). Zink could also imply "tin-like" because of its relation to German zinn meaning tin. Yet another possibility is that the word is derived from the Persian word سنگ seng meaning stone. The metal was also called Indian tin , tutanego , calamine , and spinter . German metallurgist Andreas Libavius received

4085-422: The 24th most abundant element. It also makes up 312 ppm of the solar system, where it is the 22nd most abundant element. Typical background concentrations of zinc do not exceed 1 μg/m in the atmosphere; 300 mg/kg in soil; 100 mg/kg in vegetation; 20 μg/L in freshwater and 5 μg/L in seawater. The element is normally found in association with other base metals such as copper and lead in ores . Zinc

4180-443: The 9th century AD when a distillation process was employed to make pure zinc. Alchemists burned zinc in air to form what they called " philosopher's wool " or "white snow". The element was probably named by the alchemist Paracelsus after the German word Zinke (prong, tooth). German chemist Andreas Sigismund Marggraf is credited with discovering pure metallic zinc in 1746. Work by Luigi Galvani and Alessandro Volta uncovered

4275-570: The Christian era are made of what is probably calamine brass. The oldest known pills were made of the zinc carbonates hydrozincite and smithsonite. The pills were used for sore eyes and were found aboard the Roman ship Relitto del Pozzino , wrecked in 140 BC. The Berne zinc tablet is a votive plaque dating to Roman Gaul made of an alloy that is mostly zinc. The Charaka Samhita , thought to have been written between 300 and 500 AD, mentions

4370-464: 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,

4465-654: 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

4560-478: The United States, with the largest reserves in Iran . The most recent estimate of reserve base for zinc (meets specified minimum physical criteria related to current mining and production practices) was made in 2009 and calculated to be roughly 480 Mt. Zinc reserves, on the other hand, are geologically identified ore bodies whose suitability for recovery is economically based (location, grade, quality, and quantity) at

4655-525: The Zn and Mg ions are of similar size. Zinc is the 24th most abundant element in Earth's crust and has five stable isotopes . The most common zinc ore is sphalerite (zinc blende), a zinc sulfide mineral. The largest workable lodes are in Australia, Asia, and the United States. Zinc is refined by froth flotation of the ore, roasting , and final extraction using electricity ( electrowinning ). Zinc

4750-496: 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

4845-435: The arts to stain porcelain . Zinc Zinc is a chemical element with the symbol Zn and atomic number 30. It is a slightly brittle metal at room temperature and has a shiny-greyish appearance when oxidation is removed. It is the first element in group 12 (IIB) of the periodic table . In some respects, zinc is chemically similar to magnesium : both elements exhibit only one normal oxidation state (+2), and

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4940-419: The basic zinc carbonate , Zn 5 (OH) 6 (CO 3 ) 2 , by reaction with atmospheric carbon dioxide . Zinc burns in air with a bright bluish-green flame, giving off fumes of zinc oxide . Zinc reacts readily with acids , alkalis and other non-metals. Extremely pure zinc reacts only slowly at room temperature with acids. Strong acids, such as hydrochloric or sulfuric acid , can remove

5035-420: The chromate ZnCrO 4 (one of the few colored zinc compounds) are a few examples of other common inorganic compounds of zinc. Organozinc compounds are those that contain zinc– carbon covalent bonds. Diethylzinc ( (C 2 H 5 ) 2 Zn ) is a reagent in synthetic chemistry. It was first reported in 1848 from the reaction of zinc and ethyl iodide , and was the first compound known to contain

5130-604: 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

5225-440: The developing world and is associated with many diseases. In children, deficiency causes growth retardation, delayed sexual maturation, infection susceptibility, and diarrhea . Enzymes with a zinc atom in the reactive center are widespread in biochemistry, such as alcohol dehydrogenase in humans. Consumption of excess zinc may cause ataxia , lethargy , and copper deficiency . In marine biomes, notably within polar regions,

5320-569: The effect and invented the Voltaic pile in 1800. Volta's pile consisted of a stack of simplified galvanic cells , each being one plate of copper and one of zinc connected by an electrolyte . By stacking these units in series, the Voltaic pile (or "battery") as a whole had a higher voltage, which could be used more easily than single cells. Electricity is produced because the Volta potential between

5415-533: The electrochemical properties of zinc by 1800. Corrosion -resistant zinc plating of iron ( hot-dip galvanizing ) is the major application for zinc. Other applications are in electrical batteries , small non-structural castings, and alloys such as brass. A variety of zinc compounds are commonly used, such as zinc carbonate and zinc gluconate (as dietary supplements), zinc chloride (in deodorants), zinc pyrithione (anti- dandruff shampoos), zinc sulfide (in luminescent paints), and dimethylzinc or diethylzinc in

5510-439: The formation of Zn 2 Cl 2 , a zinc compound with a +1 oxidation state. No compounds of zinc in positive oxidation states other than +1 or +2 are known. Calculations indicate that a zinc compound with the oxidation state of +4 is unlikely to exist. Zn(III) is predicted to exist in the presence of strongly electronegative trianions; however, there exists some doubt around this possibility. But in 2021 another compound

5605-591: 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

5700-439: 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

5795-461: The hydroxide Zn(OH) 2 forms as a white precipitate . In stronger alkaline solutions, this hydroxide is dissolved to form zincates ( [Zn(OH) 4 ] ). The nitrate Zn(NO 3 ) 2 , chlorate Zn(ClO 3 ) 2 , sulfate ZnSO 4 , phosphate Zn 3 (PO 4 ) 2 , molybdate ZnMoO 4 , cyanide Zn(CN) 2 , arsenite Zn(AsO 2 ) 2 , arsenate Zn(AsO 4 ) 2 ·8H 2 O and

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5890-411: 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 the diamond cubic structure. Metallic tin does not easily oxidize in air and water. The first tin alloy used on a large scale

5985-451: 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,

6080-403: 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

6175-459: The medical Lexicon ascribed to the Hindu king Madanapala (of Taka dynasty) and written about the year 1374. Smelting and extraction of impure zinc by reducing calamine with wool and other organic substances was accomplished in the 13th century in India. The Chinese did not learn of the technique until the 17th century. Alchemists burned zinc metal in air and collected the resulting zinc oxide on

6270-412: 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

6365-420: The organic laboratory. Zinc is a bluish-white, lustrous, diamagnetic metal, though most common commercial grades of the metal have a dull finish. It is somewhat less dense than iron and has a hexagonal crystal structure , with a distorted form of hexagonal close packing , in which each atom has six nearest neighbors (at 265.9 pm) in its own plane and six others at a greater distance of 290.6 pm. The metal

6460-525: The passivating layer and the subsequent reaction with the acid releases hydrogen gas. The chemistry of zinc is dominated by the +2 oxidation state. When compounds in this oxidation state are formed, the outer shell s electrons are lost, yielding a bare zinc ion with the electronic configuration [Ar]3d . In aqueous solution an octahedral complex, [Zn(H 2 O) 6 ] is the predominant species. The volatilization of zinc in combination with zinc chloride at temperatures above 285 °C indicates

6555-406: The peroxide ( ZnO 2 ), the hydride ( ZnH 2 ), and the carbide ( ZnC 2 ) are also known. Of the four halides , ZnF 2 has the most ionic character, while the others ( ZnCl 2 , ZnBr 2 , and ZnI 2 ) have relatively low melting points and are considered to have more covalent character. In weak basic solutions containing Zn ions,

6650-613: 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

6745-472: 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

6840-399: The remainder, have been found that are 2,500 years old. A possibly prehistoric statuette containing 87.5% zinc was found in a Dacian archaeological site. Strabo writing in the 1st century BC (but quoting a now lost work of the 4th century BC historian Theopompus ) mentions "drops of false silver" which when mixed with copper make brass. This may refer to small quantities of zinc that is

6935-541: The reserve lifetime for zinc has remained unchanged. About 346 million tonnes have been extracted throughout history to 2002, and scholars have estimated that about 109–305 million tonnes are in use. Five stable isotopes of zinc occur in nature, with Zn being the most abundant isotope (49.17% natural abundance ). The other isotopes found in nature are Zn (27.73%), Zn (4.04%), Zn (18.45%), and Zn (0.61%). Several dozen radioisotopes have been characterized. Zn , which has

7030-497: The rest of the d-block metals. Many alloys contain zinc, including brass. Other metals long known to form binary alloys with zinc are aluminium , antimony , bismuth , gold , iron, lead , mercury, silver , tin , magnesium , cobalt , nickel , tellurium , and sodium . Although neither zinc nor zirconium is ferromagnetic , their alloy, ZrZn 2 , exhibits ferromagnetism below 35  K . Zinc makes up about 75  ppm  (0.0075%) of Earth's crust , making it

7125-456: 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

7220-529: The same crystal structure , and in other circumstances where ionic radius is a determining factor, the chemistry of zinc has much in common with that of magnesium. In other respects, there is little similarity with the late first-row transition metals. Zinc tends to form bonds with a greater degree of covalency and much more stable complexes with N - and S - donors. Complexes of zinc are mostly 4- or 6- coordinate , although 5-coordinate complexes are known. Zinc(I) compounds are very rare. The [Zn 2 ] ion

7315-598: The second known zinc-containing enzyme in 1955. Zinc is the fourth most common metal in use, trailing only iron , aluminium , and copper with an annual production of about 13 million tonnes. The world's largest zinc producer is Nyrstar , a merger of the Australian OZ Minerals and the Belgian Umicore . About 70% of the world's zinc originates from mining, while the remaining 30% comes from recycling secondary zinc. Commercially pure zinc

7410-415: 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 , is the nonmetallic form. It

7505-516: The second millennium BC it was used in the regions currently including West India , Uzbekistan , Iran , Syria , Iraq, and Israel . Zinc metal was not produced on a large scale until the 12th century in India, though it was known to the ancient Romans and Greeks. The mines of Rajasthan have given definite evidence of zinc production going back to the 6th century BC. The oldest evidence of pure zinc comes from Zawar, in Rajasthan, as early as

7600-586: 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

7695-678: 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

7790-420: 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

7885-523: 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

7980-533: The time of determination. Since exploration and mine development is an ongoing process, the amount of zinc reserves is not a fixed number and sustainability of zinc ore supplies cannot be judged by simply extrapolating the combined mine life of today's zinc mines. This concept is well supported by data from the United States Geological Survey (USGS), which illustrates that although refined zinc production increased 80% between 1990 and 2010,

8075-588: 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

8170-423: The two metal plates makes electrons flow from the zinc to the copper and corrode the zinc. The non-magnetic character of zinc and its lack of color in solution delayed discovery of its importance to biochemistry and nutrition. This changed in 1940 when carbonic anhydrase , an enzyme that scrubs carbon dioxide from blood, was shown to have zinc in its active site . The digestive enzyme carboxypeptidase became

8265-498: The use of impure zinc in ancient times have been discovered. Zinc ores were used to make the zinc–copper alloy brass thousands of years prior to the discovery of zinc as a separate element. Judean brass from the 14th to 10th centuries BC contains 23% zinc. Knowledge of how to produce brass spread to Ancient Greece by the 7th century BC, but few varieties were made. Ornaments made of alloys containing 80–90% zinc, with lead, iron, antimony , and other metals making up

8360-606: 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

8455-473: 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 the Bronze Age . In modern times, tin

8550-458: 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

8645-593: Was isolated in Europe, it was imported from India in about 1600 CE. Postlewayt 's Universal Dictionary , a contemporary source giving technological information in Europe, did not mention zinc before 1751 but the element was studied before then. Flemish metallurgist and alchemist P. M. de Respour reported that he had extracted metallic zinc from zinc oxide in 1668. By the start of the 18th century, Étienne François Geoffroy described how zinc oxide condenses as yellow crystals on bars of iron placed above zinc ore that

8740-549: 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

8835-421: Was reported with more evidence that had the oxidation state of +3 with the formula ZnBeB 11 (CN) 12 . Zinc chemistry is similar to the chemistry of the late first-row transition metals, nickel and copper, though it has a filled d-shell and compounds are diamagnetic and mostly colorless. The ionic radii of zinc and magnesium happen to be nearly identical. Because of this some of the equivalent salts have

8930-415: 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

9025-507: Was used through 1851. German chemist Andreas Marggraf normally gets credit for isolating pure metallic zinc in the West, even though Swedish chemist Anton von Swab had distilled zinc from calamine four years previously. In his 1746 experiment, Marggraf heated a mixture of calamine and charcoal in a closed vessel without copper to obtain a metal. This procedure became commercially practical by 1752. William Champion's brother, John, patented

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