2003 d error Need HELP. Found this quarter and need help identifying. 1 1

[Jsquab37]

It's a 2003 D Illinois quarter but it has a crazy look to it and the reverse side has a large mass that looks as if it were stamped over. Please help me identify what kind of error this is and it's rarity. Thank you 

[Coinbuf]

It's been damaged by heat, not an error and worth face value of 25 cents.

[The Neophyte Numismatist]

I can feel the heat from here.  You may be lucky to find a merchant who will take it.

[Greenstang]

It is only an error if it happens during the striking of the coin. Anything that happens after that,    
such as your coin, is considered damage and adds no value.   
Still worth 25 cents, even with the damage.