This is the 2006 S US Mint 50 State Quarters Silver Proof Set. It contains 90% silver and has never been circulated. With certification from the U.S. Mint, this set includes 50 state quarters, each with a denomination of 25 cents and struck in proof quality. Minted in San Francisco with a fineness of 0.9, this set is a great addition to any coin collection. The set comes in its original government packaging (OGP) and includes a certificate of authenticity (COA). This is a great opportunity to own a piece of United States history.