Major Mint Errors on Proof U.S. coins are rare. Discovering one on a U.S. Proof Pattern is even rarer. Originally this unique major mint error was certified as a normally struck pattern. Upon further examination it was determined to have been struck on an incomplete punched planchet and was resubmitted to PCGS.
Coins struck on incomplete punched planchets are a rare occurrence. This error occurs when the blanking press only partially punches out the blanks. The sheet of metal shifts improperly. The press then fully punches out the blanks, while overlapping the partially punched ones, creating this mint error.
This pattern was designed by William Barber, who was appointed Chief Engraver of the U.S. Mint upon the death of James Longacre.
Referred to as a Standard Silver Quarter Dollar, this proof off-metal striking has a rarity of L7, was struck with a reeded edge on a copper planchet and is a Major Mint Error since it was struck on an incomplete punched planchet. This unique U.S. proof pattern mint error belongs in a collection of U.S. Patterns or in a collection of Major Mint Errors.
Proof Pattern Errors are featured in the NLG award
winning book, World's Greatest Mint Errors.