Thallium metal has not been produced in the United States since , when a sulfide smelter in Colorado stopped recovering it from flue dusts. According to industry sources, China and Kazakhstan are leading producers of thallium metal. In , a Brazilian minerals exploration company discovered a substantial thallium-rich deposit in northwest Bahia, Brazil. According to the company, the deposit is unique because it is the only known occurrence of thallium with cobalt and manganese.
The feasibility of economic production of thallium from the site has not yet been confirmed. Thallium metal is sold in various shapes and with purities ranging from Prices have recently increased substantially — at least three-fold from to — owing to relatively limited world supply.
It alloys well with other metals to form materials that feature desirable properties, such as low coefficients of friction and acid resistance. Thallium alloys are used in bearings, contact points and solders, and an alloy of thallium and mercury is used in switches and seals designed for low-temperature applications in the polar regions and in space.
Thallium compounds are used in glass lenses for digital cameras, prisms, windows for infrared detection equipment, and in repeaters used in fiber-optic networks. In recent years, thallium compounds have also been used in the development of high-temperature superconductive films, tapes and wires for magnetic energy storage, imaging and propulsion applications. Thallium is used as a dopant to increase the performance of thermoelectric materials that convert heat to electricity, and thallium isotopes are used in cardiovascular imaging.
In addition, research activity with thallium is ongoing to develop high-temperature superconducting materials for such applications as magnetic resonance imaging, storage of magnetic energy, magnetic propulsion, and electric power generation and transmission.
Also, the use of radioactive thallium compounds for medical purposes in cardiovascular imaging to detect heart disease is increasing. Subscribe to receive an email notification when a publication is added to this page.
Mineral Commodity Summaries. Skip to main content. Search Search. The raw material on which both Crookes and Lamy worked came from waste products deposited during the manufacture of sulphuric acid.
The commercial production of thallium today is not dissimilar, with the metal mostly recovered as a by-product of smelting iron, zinc or lead sulphides to make sulphur dioxide. Owing to its toxic properties, thallium has been used as a rodenticide, though there are safer ways to kill rats and the use of this chemical in the environment is now banned in many countries. Today, thallium is of greatest use to the electronics industry.
In particular, the conductivity of thallium sulphide alters on exposure to infrared light, making it an important compound in photocells. Thallium bromide-iodide crystals have also been used in infrared detectors. The addition of metals like thallium to glass can also reduce its melting point to as low as degrees centigrade. As such low-melting point glasses do not shatter like normal glasses, they are particularly useful for the manufacture of electronic parts. Thallium is also being tested in high-temperature ceramic superconductors.
Alongside the two stable isotopes, there are a further 23 radioisotopes, though most of them with fleeting half lives. One of them, thallium , is useful in nuclear medicine. This can then reveal to the clinician any part of the body not bathed in blood or where the membrane transporter is not working properly.
In particular, it is used to image the blood flow to heart muscle in patients suspected of coronary artery disease. Thankfully, with a suitably short half-life of just In The Pale Horse, Agatha Christie was not as explicit about the treatment for thallium poisoning as she was about its symptoms. That's a relief, she was OK, although you've totally blown the ending Henry! That was science writer Henry Nicholls with the story of Thallium. Next time, to the element that suits someone who doesn't want to blow up the world, maybe just a small bit of it.
When it comes to practical uses, this silvery substance is an excellent neutron emitter. This makes it handy for kick-starting nuclear reactors, where a high neutron flow is required to get the chain reaction going. It also means that, in principle, californium would make effective small scale nuclear weapons, requiring as little as five kilograms of californium to achieve critical mass - about half the amount of plutonium required for a bomb.
That's the story of Californium, which apart from its use potentially as a nuclear weapon is also useful for finding gold and striking oil. And you can join us on next week's Chemistry in its element to find out how.
I'm Chris Smith, thank you for listening and goodbye! Chemistry in its element is brought to you by the Royal Society of Chemistry and produced by thenakedscientists. There's more information and other episodes of Chemistry in its element on our website at chemistryworld. Click here to view videos about Thallium. View videos about. Help Text. Learn Chemistry : Your single route to hundreds of free-to-access chemistry teaching resources. We hope that you enjoy your visit to this Site.
We welcome your feedback. Data W. Haynes, ed. Version 1. Coursey, D. Schwab, J. Tsai, and R. Dragoset, Atomic Weights and Isotopic Compositions version 4. Periodic Table of Videos , accessed December Podcasts Produced by The Naked Scientists. Download our free Periodic Table app for mobile phones and tablets. Explore all elements. D Dysprosium Dubnium Darmstadtium.
E Europium Erbium Einsteinium. F Fluorine Francium Fermium Flerovium. G Gallium Germanium Gadolinium Gold. I Iron Indium Iodine Iridium. K Krypton. O Oxygen Osmium Oganesson.
U Uranium. V Vanadium. X Xenon. Y Yttrium Ytterbium. Z Zinc Zirconium. Membership Become a member Connect with others Supporting individuals Supporting organisations Manage my membership. Facebook Twitter LinkedIn Youtube.
Discovery date. Discovered by. William Crookes. Origin of the name. Thallium is derived from the Greek 'thallos', meaning a green twig. Melting point. Boiling point. Atomic number. Relative atomic mass. Key isotopes. Electron configuration. CAS number. ChemSpider ID. ChemSpider is a free chemical structure database. Electronegativity Pauling scale. Common oxidation states. Atomic mass. Half life. Mode of decay. Relative supply risk.
Crustal abundance ppm.
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