1999 United States Silver Proof Set about 1 1/2 ounces of pure silver KEY TO THE SERIES!!. 1999-s United States Mint Silver Proof Set with 9 coins. Produced at the San Francisco Mint, this proof sets contain a Lincoln Cent, Jefferson Nickel, Roosevelt Dime, Kennedy Half Dollar, and 5 State Quarters. The states are Delaware, Pennsylvania, New Jersey, Goergia and Connecticut. All Denominations above the Nickel are 90% Silver.