Following the success of the State Quarters commemorative coins, the U.S. Mint decided on a new program of special commemorative designs for the quarter dollar coin when the State Quarters series ended in 2009. The new designs were created under the America the Beautiful (ATB) series, which celebrated the country's various national parks. In the same way that the State Quarters were released in the order that each state was admitted into the United States, the different national sites featured on the America the Beautiful quarters are released in the order that they became an official or protected national site.
The ATB series of quarters is slated to run until 2021, marking a second consecutive decade of commemorative themes gracing America's circulating quarter dollar coins. In addition to these business strike quarters, the designs from the ATB series are always struck on much larger 5-ounce silver bullion coins in order for precious metal investors to purchase U.S. legal tender silver in bulk amounts. With 5 troy ounces of pure silver, these giant coins carry the same 25-cent denomination as their regular counterparts, but are struck from .999 fine silver.
Each 5 oz ATB quarter measures an impressive 3 inches (76.2 mm) in diameter, and features edge lettering that contains the coin's weight and purity specifications rather than the standard reeding or plain edge designs seen on most coins. In addition to their fine silver content, these 5-ounce coins are still legal tender, even if their face value of 25 Cents is only symbolic. By giving these silver coins a legal tender denomination, it affords them the full faith guarantee of the United States government for the weight and purity of their underlying precious metal content.
In addition to the standard 5 oz America the Beautiful Silver Bullion Coins™, the mint also produces special Uncirculated collector's editions of these coins. They still contain the same 5 troy ounces of pure silver and .999 fine silver purity, but feature a satin finish and bear the "W" mintmark for the West Point branch of the U.S. Mint. These America the Beautiful Five Ounce Silver Uncirculated Coins™ are intended expressly for collectors, and are offered each year along with the bullion versions of the 5-ounce silver ATB quarters.