The site is believed to be a Byzantine shipwreck, with the vessel dating to the seventh or eighth century. Researchers discovered the wreck near Mljet more than a decade ago and began systematic excavation in 2015.
Recovered items include a gold buckle set with rubies, emeralds, and pearls; a gold signet ring depicting an emperor; and coins from four Heraclian dynasty emperors.
According to researchers, the jewellery suggests the vessel was not a typical merchant ship and likely carried a wealthy, influential passenger and entourage. Pavle Dugonjic, head of Underwater Archaeology at the Croatian Conservation Institute, believes the signet ring likely belonged to someone of high status.
"This is an impressive amount of gold, the largest ever found on a shipwreck in the entire Mediterranean. It weighs over 600 grams when weighed after cleaning and restoration," he said.
The discovery offers insight into Byzantine maritime networks and the sea routes that connected the Mediterranean during the transition from the late Roman to the medieval period.
A similar Byzantine-era discovery in Israel last year uncovered 97 gold coins and fragments of gold earrings with pearls, colour gemstones, and glass.
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