Just back from a cold and grey Stonehenge, talking to an ITV crew about the bluestone story I wrote about in my last blog: there should be something on ITV news bulletins tonight.
As I was driving down thinking about it, it struck me that one of the really interesting aspect of this research is the fact that all the samples of rock matched to Pont Saeson come from chips and flakes (debitage), and not from megaliths. What does this mean?
One of the distinctive features of the rhyolitic rocks is that they are flinty – they have a good conchoidal fracture. That makes them relatively easy to break up, if they are standing as monoliths at Stonehenge. But it also makes them pretty good for making tools, or portable artefacts of some kind. There are plenty of flaked bluestone “tools” in museum collections from Stonehenge (some of them from my own dig, as illustrated above, from my PPS report). Which of these are made from debris created when stones were dressed on site? Which are made from broken up megaliths? And which were made in Wales and brought to Stonehenge by people visiting, perhaps on a pilgrimage of some kind? Clearly the distinction has important implications for how we understand Stonehenge.
These are questions that future research can answer, through excavation in Wales and at Stonehenge and study of the debris – that we can do this is a reflection of the quality and utility of the new research. Ixer and Bevins identified five groups of rock amongst the rhyolitic pieces they studied, of which three (by far the bulk of all they saw) they have matched to the Pont Saeson outcrops. There is one buried stump at Stonehenge (stone 32e) that they say could well be from Pont Saeson (to be confirmed), but the four standing rhyolitic stones are different. One of the latter (stone 48) belongs to one of the two very rare classes that Ixer and Bevins identified, which have yet to be matched to a source. One way excavation at Stonehenge would help us, is in allowing modern identification of the stumps and other bits of megaliths at the site.
Just before I set out to Stonehenge, I emailed Ixer to ask how to pronounce “Pont Saeson”. Was it Sayson or Season? He replied that Bevins always calls it Sigh-son. So now we know. (I got his message after the interview, so I used the more specific Craig Rhos-y-felin!)
One of a few things I said that probably won’t make it on air, but interesting nonetheless, are these figures, which I worked out long ago. If we imagine a complete Stonehenge (itself debatable, especially for the sarsen circle), the total weight of rock at the site would have been around 2,000 tonnes. Most of this (some 85%) was sarsen. But if you calculate tonnes/kilometre, based on assumptions about where the sources were, these two rock categories work out about the same, at 50–60,00 tonne/km. All sorts of factors complicate the issue (the sheer bulk of the big sarsens brings exceptional logistical problems, while the shorter distance would have been far less problematic than having to come from Pembrokeshire; most sarsens are likely to have been brought to the site in one go, while bluestone may – or may not – have arrived in different episodes; etc). But it’s this sort of thinking that we need more of, we need to understand the practical Stonehenge as well as the things that are impossible to know, such as why it’s there.