Minting coins isn't exactly an exact science. Even though most coins are perfect and uniform, small mistakes can result in error coins that are super valuable and ...

Some of the rarest and most valuable coins in U.S. history owe their worth to minting errors that slipped through unnoticed. Coins like the 1943 Copper Penny, struck in copper instead of wartime steel ...

Check your pockets: one of a rare batch of 1970 quarters could be worth a fortune. One of the quarters is for sale on eBayfor $35,000. The listing says it was part of a group of proof-coin errors that ...