This 2018 S U. Mint Limited Edition Silver Proof Set is a must-have for any coin collector. 25 coins made of 0.999 and 0.900 silver, all struck with proof quality. The coins were minted in San Francisco and come with a U. The set also includes an Original Government Packaging (OGP) box and a Certificate of Authenticity (COA) to ensure the authenticity of the coins. This limited edition set is perfect for those interested in collecting unique and valuable coins, and it makes for a great addition to any coin collection. Add one to your collection today!