TANTALUM (Chemical symbol ‘Ta’)
Tantalum is a grey, very heavy, and hard metal with high corrosion resistance and the highest known ability of all metals to store electricity. It is very rare, averaging 2 ppm in the earth’s crust and is remarkable for its unsurpassed performance in the diverse end uses that it serves. Only three metals have higher melting points, its tensile strength is approximately twice that of high strength alloy steels, and tantalum carbide is the harder than tungsten carbides. Tantalum metal is virtually untouched by most acids and alkalis.
Tantalum is mostly found in specialized or highly fractionated granitic rocks and their related pegmatites. It also occurs in placer deposits along with tin minerals and historically processed tin slags have been an important source of the metal.
APPLICATIONS OF TANTALUM
- Electronics: About 2/3 of all the tantalum produced is used in the construction of electronic capacitors which are fundamental to all electronic products. Its ability to store electricity in small capacitors has allowed the miniaturization of aviation electronics, miniaturization of computers to desktop and laptops, and the miniaturization of all hand held electronic devices such as cell phones, Blackberries and radios.
- Specialized Uses: Tantalum carbides are significantly harder than tungsten carbides and as such, is the preferred carbide in high-speed machine tool bits, cutting tools, and teeth for construction, mining equipment and drill bits. Its high strength, high temperature alloys find service in jet engines and other high temperature applications, and it is used directly to coat equipment that functions in highly corrosive and high temperature environments such as chemical processing plants. A new product, tantalum carbide graphite composite may be the hardest material made by man and has a melting temperature of 3738° C. Of interest, tantalum was originally used in incandescent light filaments, however its rarity and cost led to it replacement by tungsten.
- Glass: Tantalum oxide added to glass greatly increases its transparency and refractive index making possible lighter eyeglass, camera and camcorder lenses.
- Medical: Tantalum’s inertness or immunity to attack by chemicals and its non-allergenic character lend to its use in surgical appliances and prosthetic implants.
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cutting tools
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electronic components
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camera lenses
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Avalon’s Activities
Tantalum occurs in a number of minerals usually containing varied amounts of niobium, manganese, iron and tin. Avalon holds a tantalum bearing granitic pegmatite property at Separation Rapids in Northwestern Ontario in which the tantalum is found with other valuable commodities such as lithium, cesium, and rubidium. At Avalon’s Thor Lake Project in the North West Territories, tantalum is found in the heavy rare earth element bearing mineral fergusonite. Thor Lake may well be North America’s, and the world’s largest undeveloped source of tantalum.
LINKS
www.tanb.org
www.webelements.com
www.minerals.usgs.gov/minerals/pubs/commodity/tantalum
