LONDON — A missing piece of Stonehenge has been returned to Britain 60 years after it was taken, and the piece is likely to provide clues to the origins of the prehistoric monument, said English Heritage, the organization that takes care of the site, on Wednesday.
The missing stone — roughly the size and shape of a broomstick — was taken by a Briton, Robert Phillips, who worked with a diamond-cutting business at the time and emigrated to the United States around three decades ago.
Mr. Phillips took part in repair works at Stonehenge in 1958 to raise one of the trilithons, the iconic three-piece standing stones, that had fallen to the ground. The work included drilling ring-shaped holes into the stone, and it produced three-foot cylinders.
He retired to Aventura, Fla., north of Miami, according to the BBC, and kept the polished-looking stone in his office for decades. But on the eve of his 90th birthday last year, he decided to return the piece to England.
“The last thing we ever expected was to get a call from someone in America telling us they had a piece of Stonehenge,” Heather Sebire, a curator with English Heritage, said in an emailed statement. “We are very grateful to the Phillips family for bringing this intriguing piece of Stonehenge back home.”
His sons returned the stone last May, the statement said, but English Heritage did not make an announcement until the stone’s significance was understood.
The piece is expected to provide clues to a team of researchers that had been looking into the origin of the giant stones, which stand in Southern England at about 13 feet high and 7 feet wide.
So far, researchers at the University of Brighton have analyzed the chemical composition of the stones in an effort to find out where the roughly 22-ton blocks came from. They recently received permission to analyze small pieces of the recovered stone without having to drill into it. They hope to present results late this year.
“To my knowledge, it’s the only piece of sarsen stone that we can definitively link to Stonehenge,” David Nash, a professor of physical geography at the University of Brighton, who leads the research, said in a phone interview on Wednesday. (Sarsen is a term for the type of sandstone used at Stonehenge.)
According to the professor, lumps of Stonehenge can be found in museums around Britain, but the just-returned cylinder is the only one that researchers can say with any certainty came from a particular block of stone.
“Conventional wisdom suggests that the big sarsen stones are local to Stonehenge,” Professor Nash said, considering that they had to be transported to the site and laid out in a circle. Some historians believe that the circle in Wiltshire, England, may have been built for some sort of ritual more than 4,000 years ago, using sarsen for the bigger blocks and bluestone for the smaller ones. In 2015, researchers confirmed the source of the bluestone to be a quarry in Wales, but the provenance of the sarsen has not yet been identified.
These days, it would be an offense to take even the smallest piece of stone from Stonehenge. But Professor Nash said the approach to conservation was different in the 1950s.
“Normally, pieces from there would have been thrown out,” he said, referring to the work Mr. Phillips had carried out. “Nowadays, we would have kept it.”
After the return of the stone, English Heritage appealed to anyone who might be keeping other pieces of Stonehenge.
“The other two Stonehenge cores may still be out there somewhere, and if anyone has any information, we’d love to hear from them,” Ms. Sebire, of English Heritage, said in Wednesday’s statement.
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