gxseries Posted January 29, 2007 Report Share Posted January 29, 2007 Getting bored with precious metals? Copper, nickel, brass alloys etc are too common? Niobium is getting boring as well? Well there is another new type of metal that I believe is never used in any other coinages. Something caught my eye when I was looking though. http://cgi.ebay.com/ws/eBayISAPI.dll?ViewI...em=160077942695 I didn't even know what tantalum is Too bad that's way too pricy else it would have been one in my list. Here is a link from the Kazak bank: http://www.nationalbank.kz/?docid=432&...19CC5C45A1D2256 Link to comment Share on other sites More sharing options...
akdrv Posted January 29, 2007 Report Share Posted January 29, 2007 Quote from Wiki: Compounds containing tantalum are rarely encountered, and the metal does not normally cause problems in the laboratory, but it should still be handled with care, taking the usual laboratory precautions. There is some evidence that tantalum compounds can cause tumors, and its metal dust is a fire and explosion hazard. I wonder where Kazakhstan got tantalum and who minted this coin... Could be an inventive way to smuggle some rare metals out of the country. Link to comment Share on other sites More sharing options...
gxseries Posted January 29, 2007 Author Report Share Posted January 29, 2007 This metal seems quite interesting: Tantalum is a greyish silver, heavy, and very hard metal. When pure, it is ductile and can be drawn into fine wire, which can be used as a filament for evaporating metals such as aluminium. Tantalum is almost completely immune to chemical attack at temperatures below 150°C, and is attacked only by hydrofluoric acid, acidic solutions containing the fluoride ion, and free sulphur trioxide. The element has a melting point exceeded only by tungsten and rhenium. Isolation Here is a brief summary of the isolation of tantalum. Isolation of tantalum appears to be complicated. Tantalum minerals usually contain both niobium and tantalum. Since they are so similar chemically, it is difficult to separate them. Tantalum can be extracted from the ores by first fusing the ore with alkali, and then extracting the resultant mixture into hydrofluoric acid, HF. Current methodology involves the separation of tantalum from these acid solutions using a liquid-liquid extraction technique. In this process tantalum salts are extracted into the ketone MIBK (methyl isobutyl ketone, 4-methyl pentan-2-one). The niobium remains in the HF solution. After conversion to the oxide, metallic tantalum can be made by reduction with sodium or carbon. Electrolysis of molten fluorides is also used. Sources:Chiefly occurs in the mineral tantalite. Always found with niobium. Annual world production is around 840 tons. Primary mining areas are Australia, Zaire, Brazil, Russia, Norway, Canada and Madagascar. Uses: Used in metal alloys. Tantalum pentoxide is used in capacitors, condensers, cutting tools, vacuum tube filaments and in camera lenses to increase refracting power. I guess the mineral was mined from Russia? I highly doubt that Kazak coins are minted in Russia. They seem to have a mint of their own. Link to comment Share on other sites More sharing options...
Scottishmoney Posted January 29, 2007 Report Share Posted January 29, 2007 I wonder that the Austrian Mint could have manufactured these coins with materials that came in from either Kazakhstan or Russia? Link to comment Share on other sites More sharing options...
gxseries Posted January 29, 2007 Author Report Share Posted January 29, 2007 Nope, I managed to track the Kazak mint: http://www.kmd.kz/eng/ Took a bit of effort to look. Link to comment Share on other sites More sharing options...
tabbs Posted January 29, 2007 Report Share Posted January 29, 2007 Nope, I managed to track the Kazak mint: http://www.kmd.kz/eng/ Took a bit of effort to look. Hehe, funny - just a few days ago I posted this message about the World Money Fair http://www.coinpeople.com/index.php?showtopic=13492 and wrote that "this year's guest of honor is Kazakhstan; the Kazakhstan Mint will for example present a bimetallic silver-tantalium coin." That is also why the current (Feb-2007) issue of MünzenRevue has that coin (and two others from the country) on its front page, and a six-page article about Kazakhstan and its mint. The very first coins (20 tenge) were even made right here in North Rhine Westphalia, by Gräbener in Netphen. Christian Link to comment Share on other sites More sharing options...
Scottishmoney Posted January 29, 2007 Report Share Posted January 29, 2007 Nope, I managed to track the Kazak mint: http://www.kmd.kz/eng/ Took a bit of effort to look. Zhinqui - Borat would be proud Link to comment Share on other sites More sharing options...
rittenhouse Posted January 29, 2007 Report Share Posted January 29, 2007 I the late 70s I worked for a company that produced tantalum, niobium and other non-ferrous metals. Tantalum is a high temp, corrosion-resistant industrial metal used primarily in the chemical industry, heat exchangers, capacitors, and as an alloy in specialty high-strength steels.. There are several large producers in the world, two in the US. The ore principally comes from Australia, Brazil, Canada, Congo, Ethiopia, and Rwanda. Waste tailings from certain tin mines are also high in tantalum. The metal is rather soft and is a real pain to work. I wouldn't want to strike it. IMHO, coins struck in "exotic" metals are nothing more than marketing. Get collectors excited about some no-value NCLT or "commem" issue in exotic-sounding metals and separate them from their money. YAWN. Link to comment Share on other sites More sharing options...
gxseries Posted January 29, 2007 Author Report Share Posted January 29, 2007 Using Mohs scale, tantalum is at 6.5. Silver at 2.5, nickel at 4.0, Iron at 4.0. Probably something harder is Tungsten at 7.5. Other metals are probably way too expensive. I don't see how tantalum is a soft metal. Or is there something I didn't take account of??? Link to comment Share on other sites More sharing options...
bobh Posted January 29, 2007 Report Share Posted January 29, 2007 Using Mohs scale, tantalum is at 6.5. Silver at 2.5, nickel at 4.0, Iron at 4.0. Probably something harder is Tungsten at 7.5. Other metals are probably way too expensive. I don't see how tantalum is a soft metal. Or is there something I didn't take account of??? As long as the Russians don't start issuing proof sets in radioactive Pollonium ... Link to comment Share on other sites More sharing options...
Tiffibunny Posted January 30, 2007 Report Share Posted January 30, 2007 GX... you're such a metalhead. Link to comment Share on other sites More sharing options...
Mila_cent Posted January 30, 2007 Report Share Posted January 30, 2007 Here's what I found about Tantalum http://en.wikipedia.org/wiki/Tantalum Link to comment Share on other sites More sharing options...
just carl Posted January 31, 2007 Report Share Posted January 31, 2007 However, back to the original question, how about many other metals and mixtures of them or completely different materials altogether. Now what was wrong with the 43 steel cent. With a little Zinc coating they have lasted over 60 years. With modern machinery they could now be made of Stainless Steel. If the coins were made of AlNiCo for example, they would not get lost easily. Cobalt mixed with a little Radium would not be hard to find in the dark. Pure Chromium coins would stop people from wanting to clean them because they would always be nice and shinning. Coins made with a Gold/Arsenic compound would help get rid of people that put money in thier mouths. Link to comment Share on other sites More sharing options...
gxseries Posted February 23, 2008 Author Report Share Posted February 23, 2008 Got the silver-tantalum bimetal coin as a gift All I got to say is, tantalum has a wierd color look to it More information can be seen here: http://www.nationalbank.kz/index.cfm?docid...FFD1F068B2F982F Link to comment Share on other sites More sharing options...
banivechi Posted February 23, 2008 Report Share Posted February 23, 2008 I don't know much about the tantalum, but the design of this coin is much over many NCLT's. I like it! Link to comment Share on other sites More sharing options...
YeOldeCollector Posted February 23, 2008 Report Share Posted February 23, 2008 I like it! Link to comment Share on other sites More sharing options...
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