United States Mint Limited Edition 2019 Silver Proof Set. The 2019 United States Mint Limited Edition Silver Proof Set contains eight coins with stunning proof finishes. The coins included in this set are. (1) American Eagle One Ounce Silver Proof Coin with the “S” mint mark. (5) Quarters from the America the Beautiful Quarters® Program honoring. Lowell National Historical Park in Massachusetts. American Memorial Park in the Northern Mariana Islands. War in the Pacific National Historical Park in Guam. San Antonio Missions National Historical Park in Texas. Frank Church River of No Return Wilderness in Idaho. (1) Kennedy half dollar. Coins are struck in 99.9 percent fine silver.