A mule in the animal kingdom is the result of mating a male donkey with a female horse, but a mule in the coin and currency world is the result of the pairing of two dies or printing plates that were ...

A rare 2001-D Lincoln cent, a "mule error" coin with a dime reverse, has fetched over $100,000 at auction. This unique coin, created by a minting mistake in Denver, features Abraham Lincoln on the ...

There used to be a saying — “pennies make dimes and dimes make dollars” — that stressed the importance of saving your money (the phrase later showed up in a country song). Today, some Lincoln pennies ...