Nice pictures! LIBE[RT]Y looks interesting, too. The consensus is that your coin is the result of Post Mint Damage (PMD). @Fred Weinberg, the foremost authority on error coins, says it's 100% NOT a Mint error. I would keep it in case you run into another coin with damage like that...for comparison. It's certainly an interesting conversation piece!
@Carlw89. Thanks for posting the new photos. IMO the new pics validate @Fred Weinberg's opinion of PMD.
I think it looks like a piece of copper was added to the coin after it left the mint. I’m going with FW on this one.