A hard lesson for a treasure hunter by Caitlin Keating @FortuneMagazine March 19, 2012, 9:22 AM EDT E-mail Tweet Facebook Google Plus Linkedin Share icons Odyssey CEO Greg Stemm with a gold coin recovered from a shipwreck Last month two C-130 transports flew a mission from Spain to Florida to retrieve the 594,000 silver coins and other artifacts that a treasure-hunting company called Odyssey Marine Exploration OMEX recovered from a shipwreck site off the Portuguese coast in 2007 and transported to Tampa. A U.S. federal judge ordered that the treasure — perhaps the largest find in history and thought to be from a Spanish galleon sunk in 1804 by British warships — be returned to Spain. That was a blow to Odyssey, which had spent $2.6 million recovering the booty. Despite the bad news, Odyssey’s stock, which was hammered during the financial crisis, has climbed back this year largely on the prospect of new finds. The company will soon excavate the HMS Victory, which sank in the English Channel and could hold as much as three tons of gold coins. It will also — with the cooperation of the U.K. government (it seems Odyssey has learned its lesson) — forage two British ships. –Caitlin Keating This article is from the March 19, 2012 issue of Fortune.