This is quite embarrassing............

The big boulder just below and to right of centre is the one deemed by TD to be virtually identical in shape to the Newall Boulder............

The same boulder is seen just to left of centre, on the edge of the flooded area.  It is clearly not at all the same shape as claimed by TD.

Embarrassing?   ....... not for me, but for the members of the Bevins /Ixer gang who work with him.   Our old friend Tim Daw, whose trolling behaviour is in itself a source of concern, has demonstrated yet again his complete lack of understanding of the fundamentals of glacial geomorphology.

https://www.sarsen.org/2026/01/the-brian-john-boulder-again.html

https://www.researchgate.net/publication/394390618_Comparative_Analysis_of_the_Brian_John_Boulder_at_Craig_Rhos-y-felin_and_the_Newall_Boulder_from_Stonehenge_Implications_for_the_Origins_and_Transport_of_the_Bluestones?channel=doi&linkId=6894edbbd3c4ac316e2edf77&showFulltext=true

For some time he has had a weird obsession with a boulder at Rhosyfelin which he calls the "Brian John Boulder."  I'm very honoured.  There is nothing inherently fascinating about it, except that it is superficially similar in shape to the Newall Boulder (when seen from one perspective) which has been at the centre of a vigorous debate. It's also somewhat similar in shape to lots of other boulders at Rhosyfelin and elsewhere.  Just look at the photos of the archaeological dig by me and by MPP and his colleagues.  If TDS was so intent on making a big issue of the shapes of certain stones, he should have done some fieldwork and checked his assumptions first..........

I have never claimed that the Newall Boulder has a unique shape, or that the bullet shape is unique to glacially transported clasts.  Wedge or bullet shapes are common in nature, since the basic shape of blocks is determined initially by intersecting fracture patterns or joint planes.  Blocks that are narrower at one end than the other are thus very common;  more common than truly rectangular blocks, since truly rectilinear joint patterns don't occur all that often.  But as all the textbooks will tell  you, the bullet shape is accentuated or exaggerated during glacial transport because of enhanced abrasion or smoothing at the up-glacier end (where the block is under compression) and enhanced breakage at the down-glacier end (where the block is under tension). Pressure enhancement followed by pressure release and plucking or quarrying.  In my articles on the Newall Boulder I have given all the necessary sources in case you want to check this out.

The opinions on the small boulder which were expressed by 11 senior geomorphologists were based not on the bullet shape alone, but on a combination of disgnostic features.  

The TD obsession is very difficult to explain.  As far as I can see, he is obsessed with the idea that because a boulder at Rhosyfelin has a shape that is -- he assumes -- very similar to that of the Newall Boulder, and has not been transported very far, we cannot assume that the Newall Boulder was glacially entrained, transported and deposited.  The problem is that the boulder that he chooses to call the Brian John Boulder is not a glacially transported clast at all, but a locally derived block in a glaciofluvial setting. In a high energy ice wastage environment (such as that which existed at Rhosyfelin at the end of the last glacial episode) large clasts which have not been entrained and removed by true glacial processes tend to be smoothed rather rapidly by large volumes of meltwater flow.  The meltwater is turbulent and contains the silt, sand and gravel particles that are the abrasive tools.  If TD had bothered to read the articles by Dyfed Elis-Gruffydd, John Downes and myself, he would have seen that his favourite boulder sits in the middle of a somewhat discontinuous and chaotic glaciofluvial (or fluvioglacial) horizon that is stratigraphically above the local till and below the thick colluvial horizon.

The boulder which is blessed with my name has clearly had most of its sharp edges smoothed and rounded by meltwater flow. In fact the whole boulder has been affected by meltwater abrasion. Like the other boulders in this horizon, striations (if there were any to start with) have also been removed. There are no man-made features on its surface, and it holds no evidence of human quarrying activity.  It has nothing whatsoever to do with the glacial transport hypothesis, and it tells us nothing whatsoever about the origins and transport of the Newall Boulder.

Bullet-shaped clasts shaped primarily by transport on the wet bed of a glacier in the Darwin Mountains, Antarctica.  Glacier flow was from left to right.  Here the striations have survived because the boulders have not been modified by meltwater action. 

(Storey et al, 2010:  

DOI: 

10.1017/S0954102010000799)

 

Relevant text (2015):

The water-lain sediments in layer 2b are poorly-sorted,gravel-rich, and packed with rounded and sub-rounded cobbles and boulders, some of which are more than 1.5m in diameter.  Some locally-derived and sharp-edged rhyolite fragments are contained, but the erratic suite appears to be similar to that of the Devensian till. The sediments have been laid down by high-velocity, turbulent and sediment-rich streams, and the conclusion is inescapable that they are of fluvioglacial origin. There is no clear stratigraphic junction between the glacial and fluvioglacial sediments, and it is proposed that they are intimately related, having been laid down more or less contemporaneously, in an ice-wastage environment incorporating masses of dead ice. Here conditions would have been perfect for the formationof flow or melt-out tills in close proximity to clay-rich lodgement till -- and this would explain the sedimentological differences in the till exposed on different parts of the site.

OBSERVATIONS ON THE SUPPOSED “NEOLITHIC BLUESTONE QUARRY” AT CRAIG RHOSYFELIN, PEMBROKESHIRE. 

Available from: https://www.researchgate.net/publication/286775899_OBSERVATIONS_ON_THE_SUPPOSED_NEOLITHIC_BLUESTONE_QUARRY_AT_CRAIG_RHOSYFELIN_PEMBROKESHIRE[accessed Jan 15 2026].