KINGSTON, R.I. – Jan. 20, 2016 – As an underwater archaeologist in the history department at the University of Rhode Island, Bridget Buxton is trained to search for knowledge, not sunken treasure, but her most recent expedition to Israel dug up plenty of both.

Earlier this month, Buxton, an associate professor, and her colleague, John Hale, a professor at the University of Louisville, presented a poster and lecture about the largest hoard of gold coins ever discovered in Israel to the annual meeting of the Archaeological Institute of America in San Francisco.

Co-authored with Israel Underwater Antiquities Director Jacob Sharvit and scholars at the Israel Antiquities Authority, the report was the first official scholarly presentation in the United States of a discovery that made headlines worldwide last year.

In February 2015 scuba divers in Israel’s eastern Mediterranean spotted the coins, thinking they were toy coins from a game. When they realized what they had found, they alerted the Israel Antiquities Authority, which led to the recovery of 2,580 gold coins inside the ancient Roman port of Caesarea. It was the biggest hoard of gold coins ever discovered in Israel.

At the meeting, Buxton and Hale revealed what happened next. Hundreds of coins were left under the rocks and sand. Before moving anything else, it was important to make a detailed map of the area. “The excavation of a site destroys it,” said Buxton, “so we need to record all possible clues that exist.”

Buxton and the other archaeologists created a site map with the Pladypos robot brought over by the team’s Croatian partners from the Laboratory of Underwater Systems and Technology at the University of Zagreb.

The Pladypos project was funded by a grant from the Office of Naval Research-Global and private donors through Oceangate Foundation, while the excavation was paid for by the Israel Antiquities Authority.

After mapping the site with the Pladypos and removing a layer of rocks from the sea floor, Buxton and her colleagues discovered a second large pocket of coins using a Fisher Pulse 8x metal detector, bringing the total hoard to about 3,000 coins.

The most important discovery, however, was a 10-centimeter iron spike with coins cemented to either end, proof that the gold came from a wooden shipwreck that sank sometime around 1036 AD. The cause of the shipwreck and the story behind the coins remain a mystery.

“We guess that the ship was coming in to Caesarea and struck one of the semi-submerged ruins of the old Roman breakwater,” Buxton said. “What we don’t understand is how such a large amount of gold was never recovered, since the ship sank so close to shore in very shallow water.”

The team’s co-author, Robert Kool of the Israel Antiquities Authority, identified the coins as dinars minted by the Islamic Shia dynasty called the Fatimids, who ruled most of North Africa and the Holy Land on the eve of the First Crusade, which captured Jerusalem from the Fatimids in 1099, Buxton said.

Caesarea Maritima was a strategic city for the Fatimids throughout the 11th century and the gold might have been intended as pay for a local garrison, Buxton said. Salaries in the Fatimid navy ranged from 2 to 20 dinars per month at the time.

Many of the coins are from the reign of a controversial Caliph, al-Hakim, a revered figure in the Druze branch of Shia Islam, she said. The discovery is important to the Druze community, and has many implications for understanding the history of Caesarea and the organization of the Fatimid Empire.

Al-Hakim’s 24-carat gold dinars are on display in Caesarea and Jerusalem, and there are plans for a touring exhibition. Buxton and her Croatian colleagues plan to continue their underwater research with the Israel Antiquities Authority Maritime Unit in May 2016.

Applications are welcome from students and volunteers interested in joining their field program. For more information, please contact Professor Buxton at babuxton@uri.edu.

Pictured above:

Bridget Buxton, associate professor of archaeology at the University of Rhode Island, holds gold coins she retrieved during an underwater archaeological expedition in Israel.

Israel Maritime Antiquities Director Koby Sharvit holds the iron spike found during the URI expedition in July 2015, the first evidence that the gold came from a shipwreck.

Photos courtesy of Bridget Buxton.