A graphic from p 37 of the article, purporting to show the modal mineralogy of the Stonehenge volcanic bluestones. It actually shows the data for selected samples
from the Stonehenge debitage.
Rob Ixer, Richard Bevins and Duncan Pirrie
Current Archaeology 336, pp 34-41
I suppose that duty compels me to mention this article, but it's one of those that says nothing new. It is really just a summary, in a glossy format, of work already published but with the addition of some X-ray images and other graphics -- and its justification seems to be that if you repeat fallacies and fantasies often enough, they have a sporting chance of becoming "the truth."
There is no archaeological input into this paper -- the three authors are all geologists, so it is all the more disappointing that the article is packed with unproven assumptions to the extent that any "good research" contained within it is seriously devalued.
The article is supposed to be a description of a "second-generation" examination of the Stonehenge bluestones, using "new mineralogical, petrographical, and geochemical techniques" to complement older work based on established technologies including thin-section petrography and geochemistry. The automated SEM-EDS images for rhyolite and spotted dolerite point the way to more accurate provenancing in the future, but there has been no new sampling here, and until the geologists extend the range of their fieldwork they are never going to convince other specialists that they have actually found the precise locations from which much of the Stonehenge debitage has come. They still do not know how extensive the outcrops of "Carn Goedog spotted dolerite" and "Rhosyfelin foliated rhyolite" are, and they seem obsessed by the idea that the Stonehenge material has come from two quarries, because that is what Prof Mike Parker Pearson has told them. So this article has huge built-in bias. A little more independent scientific thought might not have come amiss.
The bias is apparent right from the start. In the blurb at the head of the article the authors ask "Where did the Stonehenge bluestones come from?" and then claim "Scientific advances are allowing us to pinpoint the outcrops that they were quarried from with ever-greater accuracy." In the caption of the photo at the top of page 35 we read" Excavations at the Craig Rhos-y-felin Neolithic quarry-face lie in the foreground....." So it goes on. The assumption of quarrying runs right through the article, and if that assumption is deemed (by people like me who bother to scrutinize things) to be unproven, why should one take at all seriously anything else that is contained in the text?
It gets worse. The authors say that the Rhyolite Group C debitage "only seems to match one of the buried orthostats (standing stones)." There is no physical evidence for that, apart from photos of a bluestone stump that looks as if it might be made of "laminated" rhyolite. They say that the Stonehenge Group C rhyolite debitage has "an established origin at Craig Rhos-y-felin". That is not so. An origin at that site is postulated, but not established, since the researchers have no idea how extensive the outcrop is across the landscape. They say that a Neolithic quarry site was "recognized" at Carn Goedog by Parker Pearson. The authors fail to mention that this claim is far from proven to a satisfactory scientific level, and is indeed hotly disputed. I'm mystified by the graphic caption that reads "Modal mineralogy for the Stonehenge Volcanic bluestones" because all of the data appears to come from fragments or debitage, and not from the standing or fallen monoliths themselves.
An illustration from the article, showing an automated SEM-EDS image illustrating
the fine-grained lensoidal fabric of the foliated rhyolite at Rhosyfelin. We do
not know which sampling point the sample was collected from.
Then there is talk of a prospect of "provenancing on a decimetre scale" across the "Rhosyfelin "quarry-face" and one wonders whether the authors are completely out with the fairies, given the heavy criticism already flung at them when they claimed to have done successful provenancing at Rhosyfelin "to within a few square metres" without any convincing supporting evidence and without any perfect matching of samples. This criticism has come not just from me, but from other senior earth science academics.
This is a weird statement (p 38) about Rhosyfelin: " ........there appears to be a mismatch between the quarry size and the number of orthostats removed from it – the present working surface (albeit formed by a combination of prehistoric and historical stone extraction) appears far too big for the removal of the Rhyolite Group C orthostat believed to be buried within the circle." It's the first recognition that I can recall from the geologists that there is evidence of modern stone extraction towards the top end of the exposed rock face (probably for the extraction of road-building hardcore) -- but maybe it's a first admission by the geologists that most of the quarrying at Rhosyfelin has been done by the archaeologists under the leadership of Prof MPP!
This is another weird statement on p 38, regarding the Rhyolite Group D debitage at Stonehenge: ".......it was initially thought not to be a bluestone at all; it was instead considered to be a stray rock that had little to do with Stonehenge." Since when are there "proper" bluestones and "improper bluestones" at Stonehenge? I'm not the only one to have noted that there are stones and debris from a very large number of locations (quite possibly 30 or more) at Stonehenge. If they are not sarsen stones, and if we have to used the word "bluestone" to describe them, they are foreign and they have somehow or other found their way onto the site. Or is it now only deemed proper to refer to something as a "bluestone" if it is deemed to have been quarried by our heroic ancestors? This seems to be the suggestion: "Rhyolite Group D is an entirely new and separate bluestone, quite different from any other volcanic bluestone, and therefore needs its own orthostat(s) and provenance." Why does it "need" its own orthostat? Has it not occurred to these geologists that some -- and possibly quite a lot -- of the debris at Stonehenge might have come from broken up cobbles, pebbles and small boulders rather than from the monoliths included in the Stonehenge numbering system?
A glimpse of the Altar Stone (EH photo). Never sampled........
When the authors move on from igneous rocks to sedimentaries, the text does not become any more reliable. The authors make the point that the Altar Stone and the Lower Palaeozoic sandstones are not from the Mynydd Preseli area. To quote: "......knowing their provenance has much to tell us. If they were ‘picked up’ along the way – making them ‘a secondary bluestone’ – while transporting the stones from Wales to Salisbury Plain, it informs us about possible bluestone movement routes. Conversely, if they were intentionally collected – ‘a primary bluestone’ – as a ‘cultural signifier’ somewhere far away from the Mynydd Preseli, then that vastly expands the provenance catchment area and potentially the people involved in the construction of the monument." What is extraordinary about this little extract is that it comes from three geologists -- without any archaeology input -- who appear to be in a complete state of denial about the possibility of stone movement by natural processes including glaciation.
The authors are good enough to admit that the Altar Stone has not been sampled, but in the text they still presume to know (for example in the graphic on p 39) what its geological characteristics are, and approximately where it has come from. The discussion of sedimentary sources gets tangled up in yet another piece of assumptive analysis, underpinned by the all-powerful assumptions that there had to be quarries and that the "selected monoliths" had to be shipped, rolled or dragged from Wales to Stonehenge. Again, there is no mention of ice action and ice movement directions as alternative -- and perfectly credible -- explanations for the gathering, transport and deposition of large stones and smaller debris. Are these three geologists really completely unaware of the operations of natural processes within the landscape?
On page 41, the authors conclude the article by referring to potential provenancing "hotspots" in eastern Wales, and pretend that all they have to do to solve the remaining mystery of "sandstone sources" is to find two more precise locations for the extraction of suitable monoliths. Again, there is no mention at all of natural processes even though it is known from modelling and field research that ice from eastern mid-Wales did flow southwards and south-eastwards, in exactly the right directions for the glacial transport of erratics.
I am amazed, and seriously disappointed by the poor quality of this article. But there are some signs of light. The geologists seem to have realised that most of the quarrying at Rhosyfelin has been done by Parker Pearson and his team; they have recognized that the Stonehenge bluestone monoliths and debitage have come from multiple sources, some of which are still unknown; and while the quarrying obsession persists (and may require medical intervention or a miracle vaccine to bring about a good recovery) they have at least said this: "The idea that a couple of quarries satisfied the needs of the Stonehenge builders is becoming increasingly untenable."
It's a slow process, but the geologists will get there in the end........
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