RARE KEY 2012 US Mint Silver Proof Set; Hard to get, low mintage 14 pcs – about 1 ½ ounces of pure silver.. 2012-s United States Mint Silver Proof Set with 14 coins. Produced at the San Francisco Mint, this proof sets contain a Lincoln Cent, Jefferson Nickel, Roosevelt Dime, Kennedy Half Dollar, Sacagawea Dollar, 4 Presidential Dollars and 5 America the Beautiful Quarters. The quarters are El Yunque National Forest, Chaco Culture National Historical Park, Acadia National Park, Hawaii Volcanoes National Park and Denali National Park. The Presidents are Chester Arthur, Grover Cleveland (1st Term), Grover Cleveland (2nd Term), and Benjamin Harrison. The Roosevelt 10c, all five Quarters, and Kennedy 50c piece are 90% silver.