THE search for the source of Stonehenge’s iconic Altar Stone has “intensified” as new academic research has ruled out Orkney as its original home.
The findings follow last month’s discovery that the largest “bluestone” at the heart of Stonehenge came from the Orcadian Basin of north-eastern Scotland, and not from Wales as previously thought.
When the news broke last month Orkney seemed a likely candidate for the source of the Altar Stone as the island has many Neolithic monuments and the right geological features.
However, new research examined both the five exposed Neolithic-age stones at the Stones of Stenness and seven others at the Ring of Brodgar on mainland Orkney, which are similar in size and rock type to the Altar Stone.
Researchers have concluded that the six-tonne Altar Stone at the heart of the ancient site was not sourced from Mainland Orkney but elsewhere within north-eastern Scotland.
Professor Richard Bevins from Aberystwyth University, the lead author of the new study, has been investigating Stonehenge for the last 15 years and said the research has “radically” changed his thinking about the origin of the stone.
He said: “The mystery of where the stone came from is becoming clearer and clearer as we begin to rule out specific areas in north-east Scotland. This research is radically changing our thinking about the origins of the Altar Stone. It’s thrilling to know that our chemical analysis and dating work is slowly unlocking this great mystery.
“The Altar Stone is anomalous in many ways to both the bluestones and the sarsens at Stonehenge. Whilst, at six tonnes, it is nowhere near the size of the sarsens, it is substantially larger than the bluestones, with which it has previously been classed. It lies in an unusual position at the monument, occupying a near central location and not within either the Bluestone Circle or the Bluestone Horseshoe. It is also grey-green sandstone, unlike all the other bluestone rock types.
“As an academic, I have been fascinated by Stonehenge for decades. I and my other colleagues in the team will continue to work to pin down where exactly in the north-east of Scotland the Altar Stone came from.”
Stonehenge was constructed around 5000 years ago and although it is unclear when the Altar Stone arrived at the site it is believed to have been placed within the central horseshoe of stones during the second construction phase at around 2620 – 2480 BC.
It is also not known whether the now horizontal and partially buried stone once stood upright.
The research contributes to the findings by Aberystwyth University and other UK and Australian scientists published last month which stated that the Altar Stone came from north-eastern Scotland.
It also reinforced previous research that ruled out the stones' Welsh origins and suggested that it should no longer be classified as a bluestone.
The stones' Scottish origins were originally discovered by Bevins and researchers at Aberystwyth University last month.
