Will cannonball discovery lead to lost galleon's sunken 'treasure'?

Underwater archaeologists in Japan have found a cannonball that could lead to the sunken remains of a treasure-laden Spanish galleon.

The cannonball is believed to be from the wreck of the San Francisco, a Spanish galleon that sank in a storm off the coast of Japan in 1609, the BBC reports. Experts from the University of New England in Australia, Tokai University in Japan and the U.S. are involved in the project, which is funded by the Japanese government.

Researcher Ian McCann, a graduate student at the University of New England, told Fox News that the cannonball was found during the final seconds of the team’s deepest dive, at a depth of 40 meters (131 feet).

“We were just about to head up the shot line when I noticed a round shaped concretion about 5 meters from the line, something about it looked a little different so I quickly swam across to it, scooped it up and headed up the line,” he explained via email. “As soon as I felt the weight, I knew it was something important.”