1960-D Copper-Clad Cent?

Hello Everyone!

I have a mystery for you! Perhaps you can help me figure this coin out.

I have a 1960-D Lincoln Cent that appears to be struck on a copper-clad planchet. It has the same diameter and thickness as a regular cent and it weighs 3.1g. Interestingly, the coin is magnetic, but not very strongly (strong enough to be picked up by a powerful magnet).

I understand that the US mint did not strike US copper-clad coins until 1965. Did the Denver mint stike any copper-clad foreign coins of similar size to US cents? Could this be a cent struck on a foreign planchet?

I'm sorry that I don't have any pictures to upload yet, since I am currently at work and technically the coin isn't mine, thus I can't take it home to photograph (technically because I hope to purchase it soon). The cent has a copper core with a layer of silver-colored metal on both sides of significant thickness. At first I though it was just a plated cent but the "plating" is thick enough that you can catch your fingernail on the edge of it where it meets the copper core. The "plating" does not exhibit any toning or corrosion but there are signs of wear and some heavy scratches, none of which penetrate the "plating". I considered the possibility that the piece was a complete forgery but I couldn't find any evidence for it. The details appear sharp like that of a genuine cent.

Any ideas?

Thanks.

~Sir Popalot