A first edition of the music to the US national anthem, "The Star Spangled Banner", has fetched $506,500 at a Christie's auction.
The copy is one of only 11 known copies of the first edition of the hymn written by Francis Scott Key.
The price was twice what had been estimated, Christie's said after the auction on Friday night.
Key was a lawyer and poet who wrote the patriotic music as he watched the British bombardment of Fort McHenry, near Baltimore, Maryland, during the War of 1812.
The first edition of the music is identified by a missing "T" in the title: "The Star Spangled Banner: A Pariotic (instead of Patriotic) Song".