A small gold coin from 1808 called a quarter eagle sold for $2.25 million at Tuesday's auction.
Auctioneers Sotheby's and Stack's Bowers Galleries say the price was a world record for any coin of the quarter eagle denomination.
The coins were part of the collection of D. Brent Pogue.
Pogue spent decades amassing a collection of American coins from 1792 to the 1830s.
Each steel die used to strike coins in this era was produced by hand, creating variations that are prized by collectors.
Stack's Bowers and Sotheby's are planning six more auctions of coins from Pogue's collection over the next three years.