This error or mule penny has been tested (see 3rd photo) and verified to be a CuNi coin rather than the standard copper Cu one. The composition (82% copper, 16% nickel, 2% zinc) is in keeping with a copper-nickel coin. The 1961 penny, however, has a much higher copper content (95% copper, 4% tin, 1% zinc). Such CuNi rarities have previously sold at auction for hundreds of pounds (see 4th photo) but mine has been scratched in the past, presumably to test for simple nickel plating. My reduced price reflects this scratching. Thanks for taking the time to read!
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