British family learns their flower planter is a $150,000 Roman sarcophagus

For almost a century, a British family has been using a 7-foot Roman white marble coffin as a flower planter at their home in Dorset, England.

They had no idea their rectangular "garden trough" could bring in£96,000 ($150,680 CAD) at auction.

Auction valuer Guy Schwinge, of Duke's in Dorchester, was overseeing a routine assessment of the family's property when he noticed the ancient casket.

"As I drew closer I realized I was looking at a Roman sarcophagus of exceptional quality," Schwinge told the BBC.

British Museum experts believe the 1,900-year-old sarcophagus belonged to a high-ranking official in the 2nd century, the BBC reported.

"This is a very important item. It is, to my mind, late 2nd or early 3rd century AD with carving of the highest quality," Art expert Laurence Keen OBE told the DailyMail. "The undecorated back probably suggests that it came from a private mausoleum of a high status individual where the tomb was placed against a wall."

Schwinge learned that the family acquired the coffin at a Duke's auction in 1913 — the same auction house he works for — but, over the years, the family "had come to lose the knowledge of what it was," the DailyMail reported.

Schwinge told the BBC that the family was "utterly delighted" with the sale of their flower planter. It sold for £96,000 ($150,680 CAD) at Duke's auction on September 28.