Palladium joined gold, silver and platinum in the American Eagle family through the American Eagle Palladium Bullion Coin Act of 2010, Public Law 111-303, signed December 14, 2010. The act added a $25 coin of one troy ounce of .9995 fine palladium to 31 U.S.C. 5112 and told the Mint what it should show: Adolph Weinman's Winged Liberty from the Mercury dime and the eagle of the gold medal he designed for the American Institute of Architects in 1907, both in high relief. Unlike the platinum law, it allows only the one-ounce size.
As first written, the act made the coin wait on an independent market study showing enough demand. Public Law 114-94, signed December 4, 2015, dropped that condition, and the Mint began selling bullion coins to its authorized purchasers on September 25, 2017. The first 15,000 sold out that day, according to CoinNews.
The Mint offers the bullion version only in some years: 2017 and 2021 so far. The collector version, sold by the Mint directly, has appeared every year since 2018, each time in a different finish, because the law asks that each year's proof or uncirculated surface differ in some material way from the last.
















