Mint Proof Set features five coins with a denomination of 050. 01, minted in Philadelphia. The 50, 25, 10 coins are made of 90% silver with a fineness of 0.9 and the 01 and 05 are copper and all coins are in uncirculated condition. The set includes a proof strike type and is ungraded, but comes with certification from the U. The set is a great addition to any coin collection and a piece of history from the United States.