Atocha Spanish Silver

In 1985, the wreck of Spanish ship Atocha was found, still loaded with silver and gold. A man from Georgia was a diver on that legendary find, and received two silver bars as compensation. He's long wondered about a strange mark on one of the bars. In Key West, host Tukufu Zuberi translates 300-year-old documents to crack a unique code of communication among ship captains of that era