"Carn Alw as a source of the rhyolitic component of the Stonehenge bluestones: a critical reappraisal of the petrographical account of H.H. Thomas".
Richard E. Bevins, Rob A. Ixer
Journal of Archaeological Science, In Press, Accepted Manuscript, Apr 2013
doi:10.1016/j.jas.2013.03.017
http://www.sciencedirect.com/science/article/pii/S0305440313001076
"Retracing the footsteps of H.H. Thomas: a review of his Stonehenge bluestone provenancing study".
Richard Bevins and Rob Ixer
Antiquity, May 2018.
https://doi.org/10.15184/aqy.2018.10
Published online: 31 May 2018
At the time of undertaking his Stonehenge provenancing work (in the period 1920–
1923), Thomas was not actively undertaking fieldwork in the Mynydd Preseli area, and
had to rely predominantly on the set of samples he collected in 1906 (totalling 15
samples from the whole area between Rosebush and Crymych), on 13 samples in the
survey collection from Cunnington, and on the works and specimens of Parkinson and
Part. In essence, Thomas had an incomplete and unrepresentative set of samples from
the Mynydd Preseli, and a limited opportunity to study these rocks systematically in the
field.
Quote:
Our main conclusion is that the provenances for the bluestones as presented by Thomas
are not based on reliable evidence, but appear to have been influenced predominantly by
a set of samples collected during a single field excursion to the Mynydd Preseli in 1906,
14 years before his investigation of Stonehenge. He also had to rely on samples and thin
sections from other sources, which led to a bias in the sample available for comparison;
this was especially the case for Parkinson’s thin sections, which were predominantly
from the outcrop of Carn Alw, reflecting Parkinson’s interest in spherulitic rhyolites.
Hence, Thomas’s claims about the proposed sources of the Stonehenge bluestones are
unreliable.
1923), Thomas was not actively undertaking fieldwork in the Mynydd Preseli area, and
had to rely predominantly on the set of samples he collected in 1906 (totalling 15
samples from the whole area between Rosebush and Crymych), on 13 samples in the
survey collection from Cunnington, and on the works and specimens of Parkinson and
Part. In essence, Thomas had an incomplete and unrepresentative set of samples from
the Mynydd Preseli, and a limited opportunity to study these rocks systematically in the
field.
Quote:
Our main conclusion is that the provenances for the bluestones as presented by Thomas
are not based on reliable evidence, but appear to have been influenced predominantly by
a set of samples collected during a single field excursion to the Mynydd Preseli in 1906,
14 years before his investigation of Stonehenge. He also had to rely on samples and thin
sections from other sources, which led to a bias in the sample available for comparison;
this was especially the case for Parkinson’s thin sections, which were predominantly
from the outcrop of Carn Alw, reflecting Parkinson’s interest in spherulitic rhyolites.
Hence, Thomas’s claims about the proposed sources of the Stonehenge bluestones are
unreliable.
Quote:
Our work also highlights how easy it is to accept published findings as ‘gospel’ without
challenge. This has been the case with Thomas’s paper for over 80 years.
Our work also highlights how easy it is to accept published findings as ‘gospel’ without
challenge. This has been the case with Thomas’s paper for over 80 years.
This is wonderful stuff, coming from two geologists who have produced a flood of papers over the last decade, based on hardly any new fieldwork but on detailed analyses of rock fragments of uncertain provenance and dusty old thin sections from museum collections. They criticise Thomas for depending on "an incomplete and unrepresentative set of samples", for using unreliable evidence, for using samples from the debitage rather than from the monoliths themselves, and for relying on "samples and thin sections from other sources."
They are clearly going after HHT -- and seeking to discredit him -- for failing to do proper fieldwork in which he could collect fully authenticated samples from named localities with accurate grid references..........
This is hypocrisy of the highest order, and for the last decade or so I have been criticising the two geologists and assorted colleagues for basing pretty outrageous claims (about supposedly accurate bluestone provenancing) on extremely old and unreliable samples found in dusty shoeboxes and museum display cabinets. Their sampling programmes have been hugely biased from the very beginning of their research. The argument about the authenticity of Altar Stone samples (including infamous slide 277) has gone on for many years, as outlined on this blog, and is still unresolved.
But they do not seem to learn. Here we go again, with the fiasco of the new Altar Stone provenancing work -- based on hardly any new field sampling and placing huge significance on two unauthenticated "Altar Stone" samples and two other bits of sandstone purchased from a rock shop in Whitby. That is a ludicrous state of affairs. Because of the shortcomings of their sampling programme, they have published two papers within a couple of weeks, with one showing results that are dramatically different from the other. I am not a geologist, but I really do wonder what serious independent geologists make of this palaver......... answers on a postcard please.
In an article today the "Independent" newspaper asks: "What does the latest study say on the Altar Stone?" That's not the right question. They should have asked "What does the latest study tell us about the geologists involved?"
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Interesting that CUNNINGTON is mentioned by the Ixer - Bevins duo as being a source of, I think, 13 samples of N Pembrokeshire bluestones. Down the generations, after the much - rubbished William Cunnington the First who excavated Boles Barrow in 1801, later Cunningtons have had a similar appetite for stones of exotic geological origin. Boles Long Barrow was last week being re - excavated by Richard Osgood's Operation Nightingale's army veterans. I 've been doing my best on Facebook to insist to them they should have eyes like hawks for chips, large or however small, of exotic bluestone originating in Preseli or nearby. Have they listened? Or do they plough the confirmation bias approach??
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