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Tungsten is a chemical element; it has symbol W (from ) "wolfram" on Merriam-Webster.
target="_blank" rel="nofollow"> "wolfram" on Oxford Dictionaries. and atomic number 74. It is a metal found naturally on Earth almost exclusively in compounds with other elements. It was identified as a distinct element in 1781 and first isolated as a metal in 1783. Its important include scheelite and wolframite, the latter lending the element its alternative name.
The free element is remarkable for its robustness, especially the fact that it has the highest melting point of all known elements, at . It also has the highest boiling point, at . Its density is 19.254 g/cm3, comparable with that of uranium and gold, and much higher (about 1.7 times) than that of lead. Polycrystalline tungsten is an intrinsically brittle and hardness material (under standard conditions, when uncombined), making it difficult to metalworking. However, pure single-crystalline tungsten is more ductility and can be cut with a hard-steel hacksaw.
Tungsten occurs in many alloys, which have numerous applications, including incandescent light bulb filaments, , electrodes in gas tungsten arc welding, , and radiation shielding. Tungsten's hardness and high density make it suitable for military applications in penetrating projectiles. Tungsten compounds are often used as industrial . Its largest use is in tungsten carbide, a wear-resistant material used in metalworking, mining, and construction. About 50% of tungsten is used in tungsten carbide, with the remaining major use being alloys and steels: less than 10% is used in other compounds.
Tungsten is the only metal in the third Transition metal series that is known to occur in , found in a few species of bacteria and archaea. However, tungsten interferes with molybdenum and copper metabolism and is somewhat toxic to most forms of animal life.
Of all metals in pure form, tungsten has the highest melting point (), lowest vapor pressure (at temperatures above ), and the highest tensile strength. Although carbon remains solid at higher temperatures than tungsten, carbon sublimes at atmospheric pressure instead of melting, so it has no melting point. Moreover, tungsten's most stable crystal phase does not exhibit any high-pressure-induced structural transformations for pressures up to at least 364 gigapascals. Tungsten has the lowest coefficient of thermal expansion of any pure metal. The low thermal expansion and high melting point and tensile strength of tungsten originate from strong formed between tungsten atoms by the 5d electrons. Alloying small quantities of tungsten with steel greatly increases its toughness.
Tungsten exists in two major crystallinity forms: α and β. The former has a body-centered cubic structure and is the more stable form. The structure of the beta-tungsten is called A15 cubic; it is metastable, but can coexist with the α phase at ambient conditions owing to non-equilibrium synthesis or stabilization by impurities. Contrary to the α phase which crystallizes in isometric grains, the β form exhibits a columnar Crystal habit. The α phase has one third of the electrical resistivityBean, Heather (October 19, 1998). Material Properties and Analysis Techniques for Tungsten Thin Films. frii.com and a much lower superconducting transition temperature Tc relative to the β phase: ca. 0.015 K vs. 1–4 K; mixing the two phases allows obtaining intermediate Tc values. The Tc value can also be raised by tungsten with another metal (e.g. 7.9 K for W-technetium). Such tungsten alloys are sometimes used in low-temperature superconducting circuits.
Another 34 artificial of tungsten have been characterized, the most stable of which are W with a half-life of 121.2 days, W with a half-life of 75.1 days, W with a half-life of 69.4 days, W with a half-life of 21.6 days, and W with a half-life of 23.72 h. All of the remaining radioactive isotopes have half-lives of less than 3 hours, and most of these have half-lives below 8 minutes. Tungsten also has 12 , with the most stable being W ( t½ 6.4 minutes).
The most common formal oxidation state of tungsten is +6, but it exhibits all oxidation states from −2 to +6. Tungsten typically combines with oxygen to form the yellow tungstic oxide, , which dissolves in aqueous alkaline solutions to form tungstate ions, .
( and WC) are produced by heating powdered tungsten with carbon. is resistant to chemical attack, although it reacts strongly with chlorine to form tungsten hexachloride ().
In aqueous solution, tungstate gives the and polyoxometalate under neutral and acidic conditions. As tungstate is progressively treated with acid, it first yields the soluble, metastable "paratungstate A" anion, , which over time converts to the less soluble "paratungstate B" anion, . Further acidification produces the very soluble metatungstate anion, , after which equilibrium is reached. The metatungstate ion exists as a symmetric cluster of twelve tungsten-oxygen octahedron known as the Keggin structure anion. Many other polyoxometalate anions exist as metastable species. The inclusion of a different atom such as phosphorus in place of the two central in metatungstate produces a wide variety of heteropoly acids, such as phosphotungstic acid . (2026). 9781118744994 ISBN 9781118744994
Tungsten trioxide can form intercalation compounds with alkali metals. These are known as bronzes, and have the general formula of MWO, where M is an alkali metal; an example is sodium tungsten bronze. Tungsten trioxide is also intercalated with hydrogen ions in Electrochromism devices, that is, devices that store a charge and change color.
In gaseous form, tungsten forms the diatomic species . These molecules feature a sextuple bond between tungsten atoms — the highest known bond order among radioactivity atoms.
The strategic value of tungsten came to notice in the early 20th century. British authorities acted in 1912 to free the Carrock Fell from the German owned Cumbrian Mining Company and, during World War I, restrict German access elsewhere. In World War II, tungsten played a more significant role in Wolfram Crisis Portugal, as the main European source of the element, was put under pressure from both sides because of its deposits of wolframite ore at Panasqueira. Tungsten's desirable properties such as resistance to high temperatures, its hardness and density, and its strengthening of alloys made it an important raw material for the arms industry, both as a constituent of weapons and equipment and employed in production itself, e.g., in tungsten carbide cutting tools for machining steel. (2026). 9780081004067 ISBN 9780081004067 Elemental tungsten is mostly used in the 21st century to make the alloy tungsten steel, but it also finds uses in the filaments of incandescent lamps as well as turbine blades.
Tungsten is unique amongst the elements in that it has been the subject of patent proceedings. In 1928, a US court rejected General Electric's attempt to patent it, overturning granted in 1913 to William D. Coolidge.General Electric Co. v. De Forest Radio Co., 28 F.2d 641, 643 (3rd Cir. 1928)
It is suggested that remnants of wolfram have been found in what may have been the garden of the astronomer and alchemist Tycho Brahe.
The name wolfram was accepted by the International Union of Pure and Applied Chemistry in 1949; this decision was disputed by English-speaking scientists, and the next year it was revised to reflect the widespread use of the name tungsten in that region, though the symbol W was kept. In Germany and several other European countries, the name wolfram is still preferred, while tungsten remains more common in Britain and the United States.
Even though minerals such as wolframite and scheelite are considered tungsten's main ores, their composition is rarely more than 1.5% tungsten oxide. Tungsten is separated from scheelite ore by froth flotation or gravity separation, since the crystals have a tendency to break apart into fine particles; wolfram is weakly magnetic, and so can be separated by a combination of gravity and magnetic separation methods.
The broad range of of tungsten is reflected in its various chlorides:
Organotungsten compounds are numerous and also span a range of oxidation states. Notable examples include the trigonal prismatic and octahedral , with an oxidation state of 0.
In 2025, China, Vietnam and Kazakhstan were the leading suppliers with 67,000, 3,000, and 2,400 tonnes, respectively. China is the world's leader not only in production but in export and consumption of tungsten products, and its use is strictly regulated by the Chinese government. Tungsten. Mineral Commodity Summaries. USGS (2018)
Within the European Union, the Felbertal scheelite deposit is one of the few producing tungsten mines. Portugal is one of Europe's main tungsten producers, with 121 kt of contained tungsten in mineral concentrates from 1910 to 2020, accounting for roughly 3.3% of global production. Deposits in Austria are still considered the most important throughout Europe, though operations have been repeatedly suspended due to the metal's low price.
Tungsten is considered to be a conflict mineral due to the unethical mining practices observed in the Democratic Republic of the Congo.
South Korea's Sangdong mine, one of the world's largest tungsten mines with 7,890 tonnes of High grading tungsten reportedly buried, was closed in 1994 due to low profitability but has since re-registered mining rights and resumed activities in 2026.
There is a large deposit of tungsten ore on the edge of Dartmoor in the United Kingdom, which was exploited during World War I and World War II as the Hemerdon Mine. Following increases in tungsten prices, this mine was reactivated in 2014, but ceased activities in 2018.
Tungsten can also be extracted by hydrogen reduction of , which is a common technique used to form thin films of tungsten on integrated circuits:
or pyrolysis:
Tungsten is not traded as a futures contract and cannot be tracked on exchanges like the London Metal Exchange. The tungsten industry often uses independent pricing references such as Argus Media or Metal Bulletin as a basis for contracts. The prices are usually quoted for tungsten concentrate or .Shedd, Kim B. (December 2018) Tungsten. 2016 Minerals Yearbook. USGS
The jewelry industry makes rings of sintered tungsten carbide, tungsten carbide/metal composites, and also metallic tungsten. Tungsten: The Element, History, Uses and Wedding Bands.tungstenworld.com WC/metal composite rings use nickel as the metal matrix in place of cobalt because it takes a higher luster when polished. Sometimes manufacturers or retailers refer to tungsten carbide as a metal, but it is a ceramic. Because of tungsten carbide's hardness, rings made of this material are extremely abrasion resistant, and will hold a burnished finish longer than rings made of metallic tungsten. Tungsten carbide rings are brittle, however, and may crack under a sharp blow.
Tungsten's heat resistance makes it useful in arc welding applications when combined with another highly-conductive metal such as silver or copper. The silver or copper provides the necessary conductivity and the tungsten allows the welding rod to withstand the high temperatures of the arc welding environment.
Tungsten has also been used in dense inert metal explosives, which use it as dense powder to reduce collateral damage while increasing the lethality of explosives within a small radius. Dense Inert Metal Explosive (DIME). Defense-update.com. Retrieved on 2011-08-07.
Tungsten are used in ceramic glazes and calcium/magnesium tungstates are used widely in fluorescent lighting. Crystal are used as scintillator in nuclear physics and nuclear medicine. Other salts that contain tungsten are used in the chemical and tanning industries. Tungsten oxide () is incorporated into selective catalytic reduction (SCR) catalysts found in coal-fired power plants. These catalysts convert () to nitrogen () and water () using ammonia (). The tungsten oxide helps with the physical strength of the catalyst and extends catalyst life. Tungsten containing catalysts are promising for epoxidation, oxidation, and hydrogenolysis reactions. Tungsten heteropoly acids are key component of multifunctional catalysts. Tungstates can be used as photocatalyst, while the tungsten sulfide as electrocatalyst.
Because tungsten is only 0.36% less dense than gold, and costs about a thousand times less, tungsten can also be used in counterfeiting of , such as by plating a tungsten bar with gold," Zinc Dimes, Tungsten Gold & Lost Respect ", Jim Willie, Nov 18 2009 which has been observed since the 1980s, or by taking an existing gold bar, drilling holes, and replacing the removed gold with tungsten rods. Tungsten filled Gold bars , ABC Bullion, Thursday, March 22, 2012 The densities are not exactly the same, and other properties of gold and tungsten differ, but gold-plated tungsten will pass superficial tests.
Because of its conductive properties and relative chemical inertness, tungsten is also used in , and in the emitter tips in electron-beam instruments that use field emission guns, such as electron microscopes. In electronics, tungsten is used as an interconnect material in integrated circuits, between the silicon dioxide dielectric material and the transistors. It is used in metallic films, which replace the wiring used in conventional electronics with a coat of tungsten (or molybdenum) on silicon.
The electronic structure of tungsten makes it one of the main sources for X-ray targets,Hasz, Wayne Charles et al. (August 6, 2002) "X-ray target" and also for shielding from high-energy (such as in the radiopharmaceutical industry for shielding radioactive samples of FDG). It is also used in gamma imaging as a material from which coded apertures are made, due to its excellent shielding properties. Tungsten powder is used as a filler material in plastic composites, which are used as a nontoxic substitute for lead in , lead shot, and radiation shields. Since this element's thermal expansion is similar to borosilicate glass, it is used for making glass-to-metal seals. In addition to its high melting point, when tungsten is doped with potassium, it leads to an increased shape stability (compared with non-doped tungsten). This ensures that the filament does not sag, and no undesired changes occur.
Tungsten is used in producing vibration motors, also known as mobile vibrators. These motors are integral components that provide tactile feedback to users, alerting them to incoming calls, messages, and notifications. Tungsten's high density, hardness, and wear resistance property help to endure the high-speed rotational vibrations these motors generate. (2026). 9789811567797, Springer Singapore. ISBN 9789811567797
In soil, tungsten metal oxidizes to the tungstate anion. It can be selectively or non-selectively imported by some Prokaryote and may substitute for molybdenum in certain . Its effect on the action of these enzymes is in some cases inhibitory and in others positive. The soil's chemistry determines how the tungsten polymerizes; alkaline soils cause monomeric tungstates; acidic soils cause polymeric tungstates.
Sodium tungstate and lead have been studied for their effect on . Lead was found to be lethal at low levels and sodium tungstate was much less toxic, but the tungstate completely inhibited their Reproduction.
Tungsten has been studied as a biological copper metabolic antagonist, in a role similar to the action of molybdenum. It has been found that salts may be used as biological copper chelation chemicals, similar to the tetrathiomolybdates.
It was at first believed to be a relatively inert and only slightly toxic metal, but beginning in the year 2000, tungsten alloys and their dusts and particulates were found to induce cancer and several other adverse effects in animals and humans in both in vitro and in vivo experiments.
The median lethal dose LD50 depends strongly on the animal and the method of administration and varies between 59 mg/kg (intravenous, rabbits) (2026). 9780824707651 ISBN 9780824707651 also reported in and 5000 mg/kg (tungsten metal powder, intraperitoneal, rats).
People can be exposed to tungsten in the workplace by breathing it in, swallowing it, skin contact, or eye contact. The National Institute for Occupational Safety and Health (NIOSH) has set a recommended exposure limit (REL) of 5 mg/m3 over an 8-hour workday and a short term limit of 10 mg/m3.
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