No such thing as a 1993 copper penny. All were just copper plated. Yours appears to be one where the plating didn't take or was removed for the fun of it.
It looks like the enlarged coin that was posted a while back. http://www.cointalk.org/showthread.php?t=10845
Also, could you take a picture of the coin standing on end and next to the other Cent for comparison of thickness? If it is about the same thickness as a normal Cent, then it more than likely was struck on an unplated Zinc planchet. Since the Zinc planchet is much softer without the Copper plating, the Cent spreads out to a larger diameter when struck with the Dies. If the coin is quite a bit thicker than a normal Cent, then it may be a Cent struck on a Nickel planchet. However, the color doesn't look right for a Nickel planchet! Frank
Since a nickel planchet can't fit into a cent collor or such....its not that....it would have to be either helped by a mintworker or faked...and either one is a fake no matter how you look at it. Speedy