S Mint Limited Edition Silver Proof Set OGP COA SKU:CPC6157. This official eight-coin 2020 Limited Edition Silver Proof Set from the U. Mint includes a Kennedy half dollar, Roosevelt dime, and all five America the Beautiful quarters struck in 90% silver with a proof finish. The set also includes a 1 oz American Eagle proof coin struck in 99.9% silver. All coins were struck at San Francisco and bear the “S” mint mark. Comes with the original government packaging, including a certificate of authenticity. The images you see are for the exact item you will receive. Mint Limited Edition Silver Proof Set.