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 ...

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

Manufacturing errors might be annoying when it comes to most products, but they can be a massive moneymaker when it comes to collectible money. Errors increase the value of collectibles because a ...