Archaeological excavations take place in Stonehenge
Archaeological excavations take place in Stonehenge, Britain 1958, in this handout watercolour image obtained May 7, 2019 by English Heritage. Image Credit: Reuters

London: A piece of Stonehenge that vanished from the ancient site more than 60 years ago during restoration work — and has since travelled across the Atlantic and around the United States with the man who took it as a souvenir — has finally been returned.

The pristine-looking core of one of the giant sarsen stones may now help scientists pin down one of the mysteries of the site — where the imposing hunks of sandstone came from.

During work on the stones in 1958 the tube-shaped core was removed and remained in a display case in the Hampshire office of a worker involved in the project, Robert Phillips, until he retired.

When Phillips emigrated to the United States he took it with him but as he approached his 90th year and wanted to put his affairs in order, he asked his family to make sure the souvenir was taken back to Wiltshire.

It will join English Heritage’s collection of more than 500,000 artefacts but, perhaps even more importantly, may help reveal more about the stone circle’s origins.

It is known that Stonehenge’s smaller bluestones were brought from the Preseli Hills in south-west Wales but the precise origin of the much larger sarsens is unknown.

A project, led by Professor David Nash of the University of Brighton, is investigating the chemical composition of the sarsen stones in order to pinpoint their source.

The project team have already used a hand-held portable spectrometer to investigate the chemistry of the stones using x-ray fluorescence, a non-destructive technique.

However, the core presents the team with an opportunity to analyse the unweathered interior of a stone. Nash has also been given the go-ahead to use destructive testing on a small sample of the returned core.

In 1958, archaeologists raised an entire fallen trilithon — one of the iconic structures consisting of two vertical stones with a third across the top.

Work on the Stonehenge trilithon in 1958. Photograph: The Historic England Archive

During the works, cracks were found in one of the vertical stones and in order to reinforce it, cores were drilled through the stone and metal rods inserted. The repairs were masked by small plugs cut from sarsen fragments found during excavations and are very hard to see today.

The restoration was undertaken by a diamond cutting business called Van Moppes, which had an office in Basingstoke, Hampshire.

Three 32mm holes were drilled horizontally through the one-metre thick stone. An annular drilling machine was used to bore out the holes, which resulted in three cores of approximately 25mm diameter being extracted.

Phillips worked at Van Moppes and kept one of the stone cores. For a number of years this 108cm-long piece of Stonehenge took pride of place in his office in Basingstoke.

When Phillips left the firm in 1976 and emigrated to the US, the core travelled with him. He — and the core — moved from New York to Chicago, then to California and, finally, Florida.

His sons, Robin and Lewis, have now travelled to Stonehenge and presented it to English Heritage curator Heather Sebire.

Lewis said: “Our father has always been interested in archaeology and he recognised the huge importance of the piece of the monument in his care. It was his wish that it be returned to Stonehenge. We are all delighted the core has come home, particularly as it is now being used to further important research.”

Sebire said: “The last thing we ever expected was to get a call from someone in America telling us they had a piece of Stonehenge.

“We are very grateful to the Phillips family for bringing this intriguing piece of Stonehenge back home. Studying the Stonehenge core’s ‘DNA’ could tell us more about where those sarsen stones originated.”

Nash said archaeologists and geologists have been debating where the stones used to build Stonehenge came from for years. “The bluestones have attracted a lot of attention recently, but in contrast little has been done to look at the sources of the larger sarsen stones,” he said.

“Conventional wisdom suggests that they all came from the relatively nearby Marlborough Downs but initial results from our analysis suggest that in fact the sarsens may come from more than one location.

“Our geochemical fingerprinting of the sarsens in situ at Stonehenge, and of the core itself, when compared with samples from areas across southern England, will hopefully tell us where the different stones came from.”