The Saint Gaudens $20 gold coins are the most heralded of all U.S. gold coins. Minted 1907-1933, St. Gaudens are known as Double Eagles, which means they are $20 gold coins. The only other Double Eagle gold coins are $20 Libertys, minted 1850-1907, which the Saint Gaudens superseded. Double Eagles are .900 fine (90% pure) and contain .9675 oz of gold.