Check the listing for details. 2011 S Proof National Parks ATB Quarter Set. Listed at 7.95 USD. This set features all five 2011 America the Beautiful Quarters with proof finishes. United States Mint proof coins feature sharp relief and a mirror-like background. Their sculpted, frosted foregrounds give them a special cameo effect. Proof blanks are specially treated, polished, and cleaned to ensure high-quality strikes. The blanks are then fed into presses fitted with specially polished dies and struck at least twice to ensure sharp relief. The coins are then packaged in a protective lens to showcase and maintain their exceptional finish. Specifications Denomination: Quarter Composition: 8.33% Nickel, Balance Copper Weight: 5.670 grams Diameter: 0.955 inch (24.26 mm) Edge: Reeded Mint and Mint Mark: San Francisco – S This set includes five America the Beautiful Quarters® Program coins.