Stonehenge in Wiltshire, England, has puzzled the world for centuries, yet scientists think they have finally solved at least one of its ancient mysteries—the exact site of origin of many of the huge stones that comprise it.
And its all thanks to a core sample that had been kept in the United States for decades.
The results of the two-year investigation indicate that the giant stones, known as sarsens, came from a spot about 15 miles north from where they now stand on Salisbury Plain in the ancient stone circle.
The story of the new discovery began when a core sample of one of the sarsens—“stone 58”—was extracted during conservation work in the late 1950s when metal rods were inserted to stabilize a cracked megalith.
The core sample was given as a souvenir to Robert Phillips, who was involved in the work on the iconic monument.
Phillips took it with him when he emigrated to the United States in 1977, where it stayed until, in 2018, he returned it for research to English Heritage, the conservation organization that looks after the site.
The sandstone core sample provided crucial information, enabling researchers to study the chemical make-up of the stone and compare it to similar rocks from across Southern England.
The new geochemical findings, published in the journal Science Advances, indicate that 50 of Stonehenges 52 pale-gray megaliths come from a place called West Woods on the edge of Wiltshires Marlborough Downs.
According to Timothy Darvill, a professor of Archaeology at Bournemouth University, who was involved in the study, the science involved was quite straight forward, but it was establishing provenance for the stones that was difficult because the material they are made of is very common.
“What were doing is a simple case of finger-printing. Were taking some stones at Stonehenge itself and were working out the geochemistry of them. For that, we measure all the little trace elements which are in the stone. Now, sarsens are really difficult stone to work with because its 99 percent silica and silica is a pretty ubiquitous mineral,” Darvill told Reuters.
Fifteen of Stonehenges huge sarsen stones, weighing on average 20 tonnes and standing up to 23 feet (7 meters) tall, form the monuments central horseshoe configuration. The upright and cross-stones in its outer circle, and the famous Heel Stone, Slaughter Stone, and the Station Stones are also sarsens.
There are 52 of the estimated 80 original sarsens still in place at Stonehenge. Preseli Hills in Wales, some 150 miles away, are where the other smaller “bluestones” forming its inner circle are thought to have originated.
However, “the sarsens—more homogenous in composition—have been impossible to identify until now,” English Heritage said in a statement.
“Archaeologists and geologists have been debating where the sarsen stones used to build Stonehenge came from for more than four centuries,” study lead author David Nash, professor of physical geography at the University of Brighton, said in a statement.
“This significant new data will help explain more of hRead More – Source