How can you tell if your 1943 penny is copper or steel with zinc plating?
If the coin has not been re-plated, the difference should be
obvious to look at. The zinc-coated coins will be grayish in color
rather than coppery. However, a lot of people create fake 1943
copper coins by re-plating a steel cent with copper. If you
remember back to elementary school science class, copper is not
attracted to a magnet, but steel is. Use a small magnet to test
your coin. AFAIK all genuine copper 1943 cents are accounted for
and in collections somewhere, so if yours appears to be copper I'm
willing to guess it will turn out to be plated, unfortunately.