Mint Silver Proof Set Type 2-w/Envelope-Cello Sealed Coins is a must-have for any coin collector. The set includes uncirculated Proof coins of. The Franklin Washington and Roosevelt are struck in 0.9 fineness silver and minted in Philadelphia. The coins come with U. Mint certification and are ungraded. The set is a perfect addition to any collection, with its unique cello design and sealed coins. Don’t miss the chance to own a piece of history with this stunning 1956 U. Mint Silver Proof Set.