Mint Silver Proof Set In Original Box Complete w/COA – 14 Coins. Mint Silver Proof Set is a complete collection of 14 coins, 7 struck in 0.9 fineness silver. The set includes a mix of denominations. Sacagawea Dollar & More. The coins are uncirculated and come with a Certificate of Authenticity. This set is a must-have for any coin collector or enthusiast. Feel free to ask questions or let us know if you need more scans. RATED A+ by THE BETTER BUSINESS BUREAU. Coin Appraisals Pittsburgh, Connellsville, Indiana PA, Monroeville, Altoona, State College, Uniontown, Johnstown, Greensburg.