Usually when errors happen during the production process, they lead to a decrease in value of the manufactured item. But when they happen at the U.S. Mint, they could lead to an item ballooning in ...

The error coin market has exploded in ways that would make even seasoned collectors' heads spin. What started as casual treasure hunting through pocket change has evolved into something that resembles ...

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 ...