The U.S. Presidential Coin Act of 2005 mandated the production of a one-ounce 24-karat gold bullion coin with a face value of $50.
June 2006: enter the American Buffalo Gold Coin, 99.99% pure gold!
In 2006 and 2007, Buffalo coins were only issued in a 1oz version. In 2008, Buffalo coins were minted with 1/10 oz ($5 face value), 1/4 oz ($10), and 1/2 oz ($25) of gold respectively. [Continue reading here.]