Of all the coins in circulation when America was a brassy, young country, only 20 have achieved a valuation of a million dollars or more. Of those 20, the most highly valued are the Brasher Doubloons. According to the PCGS Million Dollar Coin Club, the seven known Brasher (pronounced bray-zher) Doubloons, plus a Brasher Half-doubloon, could fetch between a million and five million dollars depending on the individual coin. What makes these gold pieces so rare and extraordinary?