Help with this lincoln cent please

[tarpon192]

What could have caused this? It may be nothing, but I never seen one like it
Thanks.

 

[TypeCoin971793]

That is a common mint error (though not worth anything). There are bubbles underneath the copper plating from an imperfect plating job in the mint process. Someone else would probably be able to explain this in better detail than I could. Since the process was relatively new (introduced in 1982), imperfections such as this were bound to happen. It is one of the more severe of this type that I have seen, but still not worth anything.