October 27-28—SACRAMENTO, CALIFORNIA: 82nd Annual Gem, Jewelry, Mineral and Rock Show; Sacramento Mineral Society; Sat. 10-5, Sun. 10-4
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 Post subject: Gold plated tungsten core metal concern
PostPosted: Thu Sep 20, 2012 4:44 pm 
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Joined: Sun Jul 22, 2007 5:58 pm
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Location: California desert
On a numismatic forum there was a post of a URL that showed a jeweler dissecting a gold plated tungsten core bar.

http://www.myfoxny.com/story/19578206/fake-gold-bars-turn-up-in-manhattan

Since tungsten has a high density 19.25 compared to gold 19.30 , it is difficult to differentiate by this characteristic. Since Tungsten has such a high melting temperature, it is usually used as a powdered chemical precipitate, rather than melted and molded. A link was given to that forum of Chinese produced coins that have tungsten cores. I happened to notice that jewelry was also listed.

http://www.tungsten-alloy.com/tungsten-alloy-fake-gold-application.html

and of course they provide this phrase " Here we declare: Please do not use our tungsten heavy alloy fake gold products for any illegal purpose."

There seems to be a waveform detector similar to an ultrascan unit that can determine a difference from the wave passing through a solid metal and through one mainly metal particles held together by an "adhesive" soft metal or epoxy.

I don't know how many use such for their work from China, but it seems this will escalate, especially from Ebay, CL, and Local auctions.

Jim


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