Archaeologists used x-rays to identify the origin of the sarsens, the rocks of up to 30 tons used in the construction of the monument.
The Stonehenge monument, dating from the Neolithic period and located in southern England, has intrigued historians and archaeologists for centuries. How was it built? What was its purpose? Where did the sandstone boulders come from?
The good news is that the last question now has an answer. New research published this week in the journal Science Advances looked at the famous giant stones, also known as sarsens, and found that they were brought from West Woods, an area located 25 km (15 miles) away from the monument with plenty of prehistoric archeological records.
According to the study’s author, David Nash, professor of physical geography at the University of Brighton, he and his team created a new technique for analyzing sarsens.
First, they used x-ray equipment to examine the composition: sarsens are made up of 99% silica, but contain traces of various other elements.
“That showed us that most of the stones have a common chemistry, which led us to identify that we’re looking for one main source here,” Nash said.
Then, they examined two samples obtained during a restoration work carried out in 1958.
The technique used in this process is called mass spectrometry, and it can detect a greater variety of elements with greater precision.
Thus, the result was compared with 20 possible sites that have sediments with the same composition. West Woods, in Wiltshire, was the closest match.
Although scientists claim that the stones were transported by land, it is not yet known how the population at the time managed to build the monument, as sarsens weigh up to 30 tons.
Its significance also remains a mystery. However, according to Nash, Stonehenge is a convergence of materials brought from different places. “I think you’re looking at a very organized society there,” he said.