An extremely rare, 224-year-old gold doubloon has been sold to a Wall Street investment firm for $7.4 million, reports AP. Minted by Ephraim Brasher, a neighbor of George Washington, the 1787 Brasher doubloon is believed to be the first American-made gold coin issued in dollars. The coin contains 26.66 grams of gold, just less than one ounce, which would make the gold value about $1,500 today. The company behind the deal did not disclose details about the seller or buyer. The US Mint in Philadelphia didn't begin producing coins until the 1790s, notes the AP. (More gold coins stories.)