MEDITERRANEAN SEA, Italy (KFOR/Storyful) – Sunken treasure is often the topic of fictional books and movies, but an ancient treasure was just discovered in the Mediterranean Sea, near the Italian island of Sardinia.

A private diver spotted something metallic in the shallow waters near the island.

The diver went in for a closer look and found roughly 50,000 bronze coins, which were all produced between 324 A.D. and 340 A.D. across the Roman Empire.

A team of archaeologists, trained for underwater digs, removed the remaining coins.

Due to their shallow location, researchers believe the treasure was the result of a shipwreck.

The Italian Ministry of Culture is working to restore the coins and will eventually put them on display. Officials did not disclose their value.

A similar discovery was made in Seaton, England, where more than 22,000 bronze coins were found on dry land in 2013.

In that case, someone using a metal detector came across the Roman coins, which dated back to 260 A.D.