The United States Mint 2011 Silver Proof Set includes a total of 1.338 oz of silver coins, all struck with a proof finish in San Francisco. This set is uncirculated and comes with a Certificate of Authenticity from the U. Mint, making it a desirable collector’s item for those interested in American coins. The coins are composed of. 9 fineness silver, adding to their value and quality for numismatists.