Now well over 40 years old, this set had a mintage lower than some later issues that sell for more today. This was the second proof set of the San Francisco Mint, which came to specialize in the minting of exquisite U.S. proof coins. Its mintage of 2.9 million was the second lowest for U.S. proof sets of the 1960s. Included in the set is one of the last 40% silver Kennedy half dollar proofs, together with the cent, nickel, dime and quarter. The U.S. Mint case displays and protects both sides of each coin.