The finest known example of the 1787 New York Brasher Doubloon will be offered at Heritage Auctions with a minimum bid of $650,000 at the January 8-12 US Coin Signature Auction in Orlando.
Ephraim Brasher was a talented gold and silversmith who famously lived on the same New York street as George Washington - who was a regular customer.
Due to the lack of a unified US currency prior to the issuing of the first dollar in 1795, there were a bewildering array of foreign coins in circulation.
Having worked for some years as an assayer (or valuer) of coinage, Brasher submitted a proposal to design a set of copper coins specifically for use in the United States.
He was turned down, but he proceeded to produce a small number of gold coins - the first pre-federal examples ever made, which have gone on to become immensely valuable.
In 2011 the famous "chest punch" doubloon, the only example featuring Brasher's hallmark on the centre of the eagle, sold for $7.4m - currently the third biggest coin auction in history.
The doubloon offered in the sale is the Perschke, Newlyn, Davis specimen and has been classified MS63 - making it the highest graded of the seven known.
Jim Halperin, co-chairman of Heritage Auctions, explained: "It will be offered without reserve during our Platinum Night auction session on January 8, 2014.
"We expect it will bring $5 million or more and set a new record as the most valuable early American gold coin ever sold at auction."
The world record for the most valuable coin at auction was set in January of this year by a 1794 Flowing Hair silver dollar - one of the first coins ever struck by the fledgling US Mint.
We have a range of rare coins available to purchase.
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