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What metal are US coins plated with?

Hi.

I'm hoping you can settle a bet for me.

A few nights ago in a bar conversation someone said our coins are plated with something called cupro. I bet him he was wrong.  I bet him a round of drinks that they're plated with nickel.

Which is it? Cupro or nickel? And what the heck is cupro?

Thank you,

Mina Farah
- Las Vegas, Nevada
2004

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2004

Cupronickel is an alloy that is mostly copper, and the rest mostly nickel. Some sources say it needs to be 30 percent nickel or less to be called cupronickel. According to the US Mint, dimes and quarters are cupronickel with a nickel content of 8-1/2 percent (basically 91.5 percent copper). They appear to be clad, with a higher concentration of copper in the center. So, although the Mint's site doesn't say, the core is probably mostly copper and the skins are probably higher than 8-1/2 percent nickel--as a guess, about 25 or 30 percent.

Sounds to me like either no rounds must be drank, or two rounds, with each of you buying one. I vote for two; let me know where and when.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey