An 1808 quarter eagle led Stack's Bowers and Sotheby's sale of the Brent D Pogue collection in New York on May 20.
The lot sold for $2.3m, setting world records for both a US quarter eagle and a 19th century US coin at auction.
It's the finest known specimen of this one year only type extant.
A 1796 quarter dollar made $1.5m, as did a 1797 half dollar - making it the most valuable half dollar ever sold.
Brian Kendrella, president of Stack's Bowers Galleries, commented: "World-class quality set new world records tonight.
"While collector interest is high in all coins across the board, we saw tonight that collectors were willing to compete strongly to own the very best condition coins in existence.
"The D. Brent Pogue Collection was built with the very highest quality as the goal, so it's no surprise that the modern generation of collectors was willing to set new world record prices to acquire them."
There will be six more auctions of pieces from the Pogue collection between now and 2017.
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