The coins, discovered by the 'Capitana' boat crew over the weekend, are believed to be those aboard 11 Spanish ships that broke apart in 1715.
Bounds and his crew found the gold approximately 200 feet off the coastline, 'New York Daily News' reported.
"You go out every day, hoping that it's gonna happen, and a lot of times it doesn't," dive boat Captain Greg Bounds told WPTV news channel.
"Eleven Spanish galleons, loaded with treasure, were sunk along the coastline out here by a hurricane (in 1715). That's what gives us the Treasure Coast," said Brent Brisben, whose company owns salvage rights.
"To see [Bounds] come up out of the water, and over the rail, I'll never forget, he waves us in.
"He says, 'I think I got one more', and he drops about 15 in my hand," Brisben added.