"Earth scientists who have worked at a "bluestone monolith quarry" site at Craig Rhosyfelin in Pembrokeshire have suggested that the archaeologists have got it all wrong, and that the so-called "engineering features" on the flank of the crag are entirely natural. Further, it is suggested that members of the digging team have unconsciously created the very features that they have cited in support of their quarrying hypothesis.
In a peer-reviewed paper published on 14th December 2015 in the peer-reviewed journal "Archaeology in Wales" journal Dr Brian John, Dr Dyfed Elis-Gruffydd and John Downes have described a set of Ice Age deposits and landforms at the site of an archaeological dig that was started in 2011, and have determined that there are no traces of human intervention in any of the features that have made the archaeologists so excited.... "
This research can be freely downloaded from Researchgate, and is also available from the journal office in hard copy.
JOHN, B.S., ELIS-GRUFFYDD, D. & DOWNES, J. (2015b). Observations on the supposed ‘Neolithic Bluestone Quarry’ at Craig Rhosyfelin, Pembrokeshire. Archaeology in Wales 54, pp 139-148.