A new study has ruled out a theory that the six-tonne Altar Stone at Stonehenge came from an area of Scotland, after tests in the Orcadian Basin failed to find a location with matching characteristics.
The 4.9-metre sandstone slab, which lies within the famous Wiltshire monument, was initially believed to have come from Wales until a more recent study pointed to north-east Scotland. Scientific tests in the Orcadian Basin area failed to find a location with matching characteristics.
Study lead Professor Duncan Pirrie from the University of South Wales said the latest investigation has left them "far better equipped to focus on the areas most likely to yield an answer." He described the publication as having "built the clearest picture yet" and being "the most comprehensive geological investigation of the Altar Stone ever undertaken."
Professor Nick Pearce from Aberystwyth University, who worked on the previous research, said "ruling out potential source areas is just as important as identifying new ones." The geochemistry expert said: "Every location eliminated narrows the search and brings us closer to discovering where the Altar Stone originated. The stone is unique among those at Stonehenge, and tracing its source would provide valuable new insights into its remarkable journey to Salisbury Plain thousands of years ago."
The world-famous monument was constructed in multiple phases between 3000 and 1600 BC. The smaller bluestones travelled around 225 km from west Wales, with research suggesting a few were taken directly from another circle.
The study combined new observations with analysis of museum fragments, examining structure, minerals and composition. It has been published in the Journal of the Geological Society.
Analysis
Why This Matters
- The Altar Stone is the largest and most distinctive of Stonehenge's non-local stones; tracing its source would reveal the extent and sophistication of Neolithic transport networks across Britain.
- Each elimination of a potential source area builds a clearer picture of the monument's construction history and the movements of its builders.
- The research demonstrates how modern geological techniques can resolve long-standing archaeological mysteries.
Background
Stonehenge, built over thousands of years on Salisbury Plain in Wiltshire, comprises several types of stone. Some, like the massive sarsens, are thought to be local; others, notably the bluestones, were transported from west Wales. The Altar Stone, a flat, six-tonne sandstone slab, has been the subject of debate, with earlier studies suggesting it came from Wales, then more recently from north-east Scotland. The latest study investigates the Orcadian Basin, a geological region spanning parts of northern Scotland.
Key Perspectives
Professor Duncan Pirrie (University of South Wales): says the latest investigation means researchers are "far better equipped to focus on the areas most likely to yield an answer."
Professor Nick Pearce (Aberystwyth University): says ruling out potential source areas is as important as identifying new ones, and that every elimination narrows the search.
What to Watch
- Whether further geological surveys in other parts of Scotland, outside the Orcadian Basin, produce a match for the stone's composition.
- If new museum fragments or analysis techniques emerge that could refine the search.
- Any field investigations at potential source sites identified by the narrowed search area.
Checked
12 claims in this story checked against 1 source: 12 supported.
Show each claim
- SupportedA new study rules out the theory that the Altar Stone came from Scotland.BBC News: “A new study exploring the origins of the six tonne Altar Stone at Stonehenge has ruled out a theory that it came from an area of Scotland.”
- SupportedA geological investigation narrows the search for the source of the six-tonne slab.BBC News: “Every location eliminated narrows the search”
- SupportedThe Altar Stone weighs six tonnes.BBC News: “the six tonne Altar Stone at Stonehenge”
- SupportedThe Altar Stone is a 4.9-metre sandstone slab.BBC News: “The 4.9 metre sandstone slab within the circle”
- SupportedThe stone was initially believed to have come from Wales, while a more recent study pointed to north-east Scotland.BBC News: “The 4.9 metre sandstone slab within the circle was initially believed to have originated in Wales until a more recent study pointed towards it coming from north east Scotland.”
- SupportedTests in Scotland’s Orcadian Basin failed to find a location with the same characteristics as the stone.BBC News: “Scientific tests were carried out in the Orcadian Basin area of Scotland, but researchers failed to find a location with the same characteristics of the stone in that area.”
- SupportedDuncan Pirrie said the investigation left researchers “far better equipped to focus on the areas most likely to yield an answer.”BBC News: “the latest investigation has left them "far better equipped to focus on the areas most likely to yield an answer."”
- SupportedPirrie said the publication had “built the clearest picture yet”.BBC News: “Pirrie said his latest publication on the Altar Stone has "built the clearest picture yet"”
- SupportedPirrie described it as “the most comprehensive geological investigation of the Altar Stone ever undertaken.”BBC News: “was "the most comprehensive geological investigation of the Altar Stone ever undertaken".”
- SupportedNick Pearce, who worked on the previous research, said “ruling out potential source areas is just as important as identifying new ones.”BBC News: “Professor Nick Pearce from Aberystwyth University, who worked on the previous research, said "ruling out potential source areas is just as important as identifying new ones".”
- SupportedThe geochemistry expert said, “Every location eliminated narrows the search and brings us closer to discovering where the Altar Stone originated.”BBC News: “The geochemistry expert said: "Every location eliminated narrows the search and brings us closer to discovering where the Altar Stone originated.”
- SupportedThe geochemistry expert said the stone is unique among Stonehenge’s stones and tracing its source would provide insights into its journey to Salisbury Plain.BBC News: “The stone is unique among those at Stonehenge, and tracing its source would provide valuable new insights into its remarkable journey to Salisbury Plain thousands of years ago.”
