Definitions of some types of Error coins

Clipped Planchet: An incomplete coin that is missing 10-25% of the metal.

Multiple Strike: A coin that has additional image from being struck again off center.

Blank: A blank of metal intended for coinage but never struck with the dies.

Defective Die: A defective die will cause a coin to show raised metal or have a small rim break.

Off Center: A coin that has been struck out of collar and incorrectly centered with part of the design missing.

Broadstrike: A coin that was struck outside of the retaining collar.

Lamination: A flaw with a fragment of metal peeled off the coin's surface.

Brokerage: An error that reflects a mirror image of the design impressed on the opposite side of the same coin.

Wrong Planchet: A coin that is struck on a planchet designed for another denomination or metal.

Overstrike: A new coin produced with a previously struck coin used as the planchet.