The story
Congress answered the Krugerrand era with a bullion coin wrapped in Saint-Gaudens' 1907 Liberty. The Gold Eagle became the standard US retail gold unit: legal tender at a nominal $50, IRA-eligible, and backed by law requiring its gold be newly mined in America. At current prices one coin carries about $4,600 of metal — 92 times its face value.
The alloy recipe — 3% silver, ~5.3% copper — is a deliberate echo of the historic US 'coin gold' standard, chosen so the coins wear like their 1907 ancestors.