"It's the Klopman Diamond. A rare and priceless gem, as well as a pointless running gag on a Saturday morning cartoon show."
The Klopman Diamond is a legendary diamond said to have a curse on it.
- The Guy of Her Dreams (mentioned only)
- The joke was referenced in Garfield's Pet Force as The Klopman Crystal, a powerful diamond Vetvix was after.
- In a few episodes of The Garfield Show, Garfield watches a documentary named Who Stole The Klopman Diamond.
- The origin of the Klopman Diamond is an old joke usually associated with either Myron Cohen or Johnny Carson. Mark Evanier loved this joke so much that he put a reference in the scripts. According to him, at the recording session, all the actors instantly recognized the joke.