A British man who unearthed an estimated 670-year-old medieval ring in the late 1970s recently rediscovered it hidden in storage boxes — and learned the forgotten treasure is reportedly worth thousands of dollars.

Tom Clark, 81, who is retired, told SWNS he found the ring using a metal detector while treasure-hunting on farmland near Aylesbury, England, in 1979.

MYSTERIOUS MEDIEVAL SKELETON AT PRAGUE CASTLE REVEALS ITS SECRETS

He kept the find, placing it in a metal tin and stowing it away in his mother’s garage. He forgot about the ring for decades — until recently, when Clark was rummaging through some boxes that he once kept at his mother’s house.

“At the time, I’d only been metal-detecting for 10 years and didn’t realize the ring was anything special,” Clark told SWNS. “It was all twisted and broken when I dug it up.”

Using his now more than 50 years of treasure-hunting experience, when he rediscovered the historic jewelry item Clark estimated the ring was hundreds of years old.

“I knew straight away it was a seal ring dating back to around 1350. I had the shank of the ring mended, luckily the head was intact,” he said.

His hunch was seemingly spot on. Clark confirmed the ring dates back to the Middle Ages and is made with the “highest carat gold and would have belonged to someone of importance due to its decoration and quality,” he said.

“The dark green intaglio features the god Mars holding a spear and trophy. It’s rare and elegant. I’d love to know who it belonged to.”

A Latin inscription, NVNCIE.VERA.TEGO, is engraved on the ring. According to SWNS, the words may translate to “I hide the true message.”

“This could relate to the role of a seal ring in securing correspondence,” Mark Becher, Historica expert at Hansons Auctioneers, a U.K.-based auction house that is selling the ring, said of the inscription.

FEMALE VIKING WARRIOR'S REMARKABLE GRAVE SHEDS NEW LIGHT ON ANCIENT SOCIETY

"It’s a fascinating piece of medieval jewelry and I’m delighted Tom rediscovered again after all these years,” he added.

The ring will be auctioned off on Aug. 27 and is expected to sell for an estimated $10,000 to $12,000.