The doubled die coin is “a variety created during the die making process,” according to NGC. “As a result, the doubling will appear on every coin struck from that die. If the hub (a steel ...

This doubled die nickel is unique. According to PCGS, doubling is when there is a mistake during the minting process. For example, the date might be doubled on the coin. There is a difference ...

Mint errors, such as off-center strikes or double dies, can significantly increase a coin's worth because of their rarity and unique value as a collectible. This first-year issue is highly sought ...

A rare "double eagle" coin was recently sold at an auction in California for over $1 million. Enthusiastic coin collectors eagerly vied for the rare $20 "double eagle" gold coin during the auction ...