Newall's ignimbrite boulder (update)

 

I have come across a number of references to a strange boulder of Ordovician ignimbrite which was found during Col Hawley's excavations at Stonehenge in the 1920's, together with "other striated erratics." These were assumed to be metamorphic rocks of Welsh origin. Apparently some of the archaeologists at the time of excavation thought the stones were glacially derived, although Hawley would have none of it. According to legend, the stones were shaped by ice, faceted, and some had striations on them. James Scourse discusses this on pp 285 and 287 of his chapter in the "Science and Stonehenge" book, and tends to dismiss the evidence as unreliable. But I'm not so sure, and tend to be more trusting of the word of Newall and Kellaway....... not to mention the apparent agreement of Dale and Engleheart with reference to a glacial origin for this material.

Newall kept the "boulder" and other material for almost half a century, and then passed it on to Geoffrey Kellaway around 1969-71. Kellaway took photos of the boulder and published them here in 1991: "The older Plio-Pleistocene glaciations of the region around Bath." In Kellaway, GA (ed) Hot Springs of Bath, pp 243-41. I have not seen this article or the photos, but Scourse describes the boulder in question as a "sub-angular to sub-rounded, faceted and bleached clast". Scourse also says that the signs of striae are not clear enough to be convincing.

Thorpe et al tried to trace this boulder, but could not find it. So what happened to this little Newall collection? Geoffrey Kellaway sadly died in 2013 -- is the boulder still in the possession of his family, or has it ended up somewhere else?

Anyway, thanks to Philip for scanning the two images from Kellaway's paper.  They are BGS photos, which means that he took them during the course of his official work.  I have no reason to doubt Kellaway's word on the "erratics" found by Hawley, or the existence of the "Newall boulder", or the authenticity of the photos.  The boulder recorded here wasn't very big, maybe c 25 cm x 12 cms and weighing in at c 10 kg.  

If Kellway says the boulder was an "ignimbritic tuff-lava" probably of Ordovician age and possibly originating in North Wales, I am prepared to accept that until somebody comes up with a more accurate piece of provenancing.  His comments about weathering are also quite sensible, as are those on the striations -- he says they "may be" of glacial origin.  The images are not clear enough to pick up detailed surface markings.

It would be disrespectful of a good scientist to simply dismiss this evidence out of hand, and unless anybody has a better explanation for its presence at Stonehenge, embedded in chalky rubble,  I think we are duty bound to accept it as evidence of glaciation at Stonehenge.

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Click to expand.  RSN-18 is presumably Newall's sample number.

PS.  Thanks to Philip, here is the text relating to the boulder.  In spite of a somewhat convoluted discussion of its origins, it seems to be carefully thought out.  We can forget about the "Pliocene glaciation" which was one of Kellaway's pet theories and concentrate on the provenancing discussion and on the "context" of the erratic.  The fact that the stone was not found in "a secure archaeological context" will no doubt be used in some quarters as an argument for simply forgetting about it, or pretending that it is simply "adventitious."  I do not accept that for a moment.  It was certainly not carted to Stonehenge as a piece of roadstone.   All that we know from the context is that somebody foolishly thought the stone was of no interest, and threw it out.  That was a silly thing to do, since its presence at Stonehenge might actually be rather important.

Glacial landscape effects in Pembrokeshire

 

Glacially eroded and sculptured landscape on the cliffs of Pencaer.  The Strumble Head lighthouse can be seen in the distance.  In the foreground, overriding ice (during the LGM) has removed almost all of the superficial deposits, leaving expansive areas of bare rock exposed.  I have never quite worked out why sediment removal has been more efficient here than in other coastal locations.......

The coastline at Pem Morfa (Morfa Head) on the north side of Newport Bay.  The left embayment seems to have been modified by meltwater flow exploiting a fault line, but the one in the centre of the photo has been dramatically modified through landsliding and slumping processes.  As on other sections of the coast between Newport and Ceibwr, I suspect that this might be due to pressure release following the wastage of Irish Sea ice along the cliffline. 

A very unstable coastline at Cell Howell, SW of Ceibwr.  Here, for a distance of almost 2 km, the whole cliffline is subject to large-scale slumping, causing the frequent realignment of the coastal footpath.

A more or less semi-circular landslide scar at Cell Howell.  Landsliding and sediment flowage processes are still very active.

Another active semi-circular landslide scar at Cell Howell.  There have been multiple phases of movement.

The oblique photos above are stills from an S4C film  -- very relaxing it is -- which follows the whole coast of Wales, filmed from a light aircraft. If you want to watch the whole film, set aside 4 hours of your time and enjoy it in a gently meditative state.........

https://www.youtube.com/watch?v=iQw3o-uuhiI

 

Senams in Libya

 

Just for fun, this is one of the megalithic structures (age unknown, but apparently pre-Roman) called "senams" in Libya.   Apparently in some of the strange structures (there are hundreds of them) the builders used woodworking methods, as at Stonehenge. Looks familiar?  Was Stonehenge built by an itinerant group of Arab senam builders?

 

Link:

https://archive.org/details/hillgracesareco01cowpgoog/page/n176/mode/2up

The Bluestone Stumps

This is a very useful page for reference from Simon Banton's excellent "Stones of Stonehenge" web site.   It covers the 11 stumps which for one reason or another are not visible at the surface.  Some have been sampled and studied, and others not.........

The map above is from Anthony Johnson's book, annotated by Simon.  Link:

 http://www.stonesofstonehenge.org.uk/search/label/Stumps

Salisbury Plain -- no traces of ice action? Think again......

It's a standard tactic used by archaeologists, when one talks of the glacial transport of monoliths from West Wales to Salisbury Plain, to say "There are no traces of glaciation anywhere in Wiltshire.  Therefore, even if glaciation was possible, it did not happen."  That is a bit disingenuous, given that there are abundant "inconvenient stones" whose presence is only explicable, in my view, by reference to the work of ice.  For a start there are the Stonehenge bluestones themselves -- in the bluestone circle, as fine a collection of weathered and abraded glacial erratics as you are likely to find anywhere in the world.  (Admittedly those in the bluestone horseshoe are shaped into pillars, but one does not have a problem with that.)  Then we have the thousands of fragments of stones of many types in the Stonehenge debitage, some of which have been examined by the geologists and found to have come from many exotic locations.  Since only about 50% of the surface area of the stone monument has been excavated, logic dictates that there must be many thousands more exotic fragments, as yet undiscovered.

Then there are all the stones further afield.  This is an extract from my book "The Stonehenge Bluestones",  written in 2018.  Some bits of the text have been overtaken by events, but even if some of the "finds" recorded are not now thought to be bluestone fragments and cobbles, there have been other finds to expand the list -- many of these already dealt with on this blog.

It is true that there are no confirmed morainic mounds or exotic monoliths littering the ground surface, but the argument that Stonehenge was built (or partly built) with stones of all sizes that were littered across the landscape is perfectly valid.  So what is there still to be discovered within the Salisbury Plain sediments?  To say that there are no foreign stones on the chalklands, when probably less than 1% of the surface has ever been investigated, is patently absurd..........

And if the "human importation" hypothesis is your thing, did the local Neolithic tribes import "rubbish stone" from here and there (and always in the west) just to scatter it about at random?

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Salisbury Plain and the Inconvenient stones

Ever since the days of Judd, Hawley and the geologists brought in to advise on stone types and provenance, it has been known that Salisbury Plain is littered with foreign stones and fragments. In 2009 Tim Darvill said: “Beyond the Stonehenge Landscape there are pieces of bluestone scattered across central southern England......”   Because most of the digging into the soil horizons has been done in the course of archaeological investigations, most of the discoveries have been assumed to be linked in some way with human activity. This again might involve circular reasoning, since small stones and boulders might have been in place in a locality prior to the ground disturbance associated with the building of Neolithic barrows or ritual features, and might simply have been moved about prior to incorporation in these man-made structures. They might even have been a nuisance. There is often a tendency to assume that all finds (for example, of bluestone fragments) are significant -- but they may equally well be insignificant in the sense that they are not actually associated with stone working of any sort. There is a need to differentiate between worked fragments and natural or locally-occurring fragments -- and this is not always done.

That having been said, we can learn a lot from the occurrence of foreign stones found in long barrow and other excavations. We have already seen how the presence of a spotted dolerite boulder in Boles Barrow caused confusion in archaeological ranks, on the basis that in terms of chronology and “human motivation”, it was not supposed to be there. The Jurassic Limestone blocks in Berwick St James are also “inconvenient” in the same sense. Richard Thorpe and his colleagues assembled information in 1991 relating to other intriguing stone finds: for example, a piece of rhyolite found near Avebury, a spotted dolerite stone from near Lake, a piece of rhyolite from a very early Neolithic pit fill on King Barrow Ridge (associated with pre-grooved pottery fragments and probably more than 4500 years old), and fragments of quartz diorite, hornblende diorite and granidiorite in the long barrow numbered Amesbury 39. There are also assemblages of foreign stones at Windmill Hill. Maskelyne and Judd were also quite certain of the presence of sedimentary rock fragments including greywackes, flagstones and shales, and metamorphic rocks including slates -- all discovered in the spoil from archaeological digs. Dolerites (spotted and unspotted), rhyolites and sandstones “of the Altar Stone type” were also recorded by Cunnington, Colt Hoare and other early workers, and by archaeologists including Julian Richards in more recent times. At least twenty “bluestones” have been listed by the Wessex Archaeological Trust in the Stonehenge environs but outside the monument itself. There are thousands of bluestone fragments in the old collections and in the sediments within the Aubrey Holes.

The recent excavations at Durrington Walls, Windmill Hill and the Cursus have been particularly revealing, throwing up bits of bluestone with alarming frequency. Many of these occurrences have been listed on Stonehenge blog sites and on other segments of Stonehenge cyberspace -- and while some fragments have undoubtedly been misidentified and while others may truly be “adventitious”, many of them have come from meaningful archaeological contexts. For example, bluestone fragments from the Cursus are now being found and identified. Rob Ixer has identified some of JF Stone’s 1947 finds from the Cursus and Fargo Wood as “acid volcanics and tuffs” and also spotted dolerite. Some seemed to be calcareous ashes. In 2008 a further “bluestone” from the fill of the Cursus pit was identified as identical to one of the sandstone stumps in the Stonehenge bluestone circle. That is potentially very significant, since it means the lump of (Ordovician?) sandstone was present before 5,200 BP in this very early earthwork. Just like the Boles Barrow spotted dolerite boulder, that is very inconvenient indeed if you happen to subscribe to the human transport theory, but not at all inconvenient if you happen to think that the bluestones on Salisbury Plain are glacial erratics……….

And in addition to these recorded finds there are the rumours. One rumour was that Richard Atkinson found a lump of bluestone on Silbury Hill when he was working there. The find is unrecorded in the published literature, and attempts to verify it through English Heritage in 2008 got nowhere. But suddenly it has appeared in the Alexander Keiller Museum in Avebury, with a note that it was found in 1970. It would be natural enough for Atkinson to be considerably embarrassed by such a find, since it would have been wildly out of context according to his view of the Neolithic world. But when one digs into the literature, one finds that at least 1300 bluestone fragments are reputed to have been found on or inside the hill! Have they all been misidentified? That’s very unlikely.  In an article published in 1991 Geoffrey Kellaway claimed to have in his possession a boulder of Ordovician ignimbrite (a highly brecciated rock resulting from an explosive volcanic eruption) found at Stonehenge during Howley’s excavations during the 1920‘s. Robert Newall kept possession of the boulder for more than half a century before passing it to Kellaway -- but it has now disappeared. Other rumours involve a cluster of bluestones in a garden and a strange boulder in a hedge somewhere else on Salisbury Plain. Delicate negotiations are necessary with a view to these stones being examined and identified as to rock type. They may or may not be significant. Bluestone monoliths were indeed taken from Stonehenge and used for ornamental or building purposes -- and in these cases the shapes of the stones may prove to be more revealing than their lithology.

When people say (as they often do) that the bluestones cannot be glacial erratics because there are no others anywhere on Salisbury Plain, they are clearly wrong. It is true that there are no large bluestone monoliths known on the chalklands, but there are certainly quite abundant smaller bluestones, and we should always bear in mind the old dictum that absence of evidence is not evidence of absence. Who knows what might still turn up, maybe on the extensive terrains currently occupied by the armed forces and inadequately explored?

The Cunnington slides -- and some andesite

Andesite from Trefgarn Gorge

Thanks to Tony for drawing attention to this small item about the 34 lost Cunnington slides, the analyses of which are of course of interest to some geologists and some bloggers.  Here is the item from the Wiltshire Museum:

Museum stores shine light on Stonehenge

16TH FEBRUARY 2022 NEWS

A rediscovery in our Museum stores featured in the February 2022 British Archaeology Magazine with an article by Mike Pitts.

Stonehenge must be as thoroughly researched as any ancient site in the world. Yet important evidence can still be found in museum archives.

The discovery identified in the Wiltshire Museum, Devizes by director David Dawson, consists of three wallets containing 34 geological thin sections, made for William Cunnington III from specimens collected “from under the turf within the area of the [Stonehenge] building” between 1876 and 1881. Though known to have been made, they were thought lost. They are of considerable interest to geologists, as few such early collections remain extant. They also hold important new clues about the nature of the bluestones, the small megaliths at Stonehenge mostly sourced in Wales.

The samples allow new descriptions of three stones. Numbers 32 and 61a are dolerite. Because thin sections cannot be analysed geochemically, the slides add to existing characterisations without changing them. Stone 32c, however, had not been scientifically studied before. It can now be allocated to “Andesite Group A”, say Rob Ixer and Richard Bevins, which they had previously defined using broken debris alone. It is the first megalith – and the slide is now the type specimen – to be scientifically assigned to this large group of material to which four other stones had been attributed by eye. Its source is thought to be somewhere in north Pembrokeshire. In addition, one of Cunnington’s samples proved to be an example of Ixer and Bevins’s “Dacite Group D”, one of only two known instances of this rock type from the Stonehenge monument.

Mike Pitts, British Archaeology magazine February 2022

The microscope and slides will be displayed at the Museum later in the Spring.

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No doubt there will be another paper from Ixer and Bevins in due course, and while there are no earth-shattering revelations here, I'm interested to see the references to dacite and andesite.  There's dacite on Carningli near Newport, and in other locations.  There are many references to dacite fragments in the Stonehenge debitage, but andesite is rather more interesting.  There isn't any andesite, to the best of my knowledge, in Mynydd Preseli, but there are outcrops which were quarried for many years in the Trefgarn Gorge.  Has some of the debris at Stonehenge come from Trefgarn?  All will be revealed.......  but as the list of bluestone provenances inexorably builds up, for how much longer will MPP and his merry gang be able to maintain the fantasy of the bluestone quarries?

Ref:  

A re-appraisal of the petrogenesis and tectonic setting of the Ordovician Fishguard Volcanic Group, SW Wales

Published online by Cambridge University Press: 28 July 2015
BETHAN A. PHILLIPS, ANDREW C. KERR and RICHARD BEVINS

(behind a paywall)

The Stonehenge phenomenon: red alert

This is an interesting article which deserves to be taken seriously by archaeologists and maybe sociologists as well.........

Opinion: “Stonehenge is no longer a Neolithic monument – it is a pop culture phenomenon”

Dr Kenny Brophy

BBC History Extra
Feb 17, 2022

Viewing all of Neolithic Britain through the lens of one monument shuts down an understanding of the diversity of the period, writes Dr Kenny Brophy, head of the archaeology department at the University of Glasgow.

https://www.historyextra.com/period/21st-century/opinion-stonehenge-monument-celebrity-fame-how-we-understand-neolithic-britain/

What interests me particularly about the article is not so much the status of Stonehenge as an icon, or an EH cash cow, or even a "pop culture phenomenon", but the manner in which "the Stonehenge story" (or myth as we should really call it) has been turned into a belief system.  Large numbers of people have been drawn to the narrative not just at an intellectual level but at a spiritual or almost religious level -- and that is more than a little frightening.  There is a Stonehenge cult out there -- and of course this is encouraged by the style of EH marketing, with the high point being the "midsummer sunrise" event which attracts thousands of "believers"(and not just the druids)  to the old ruin every year, very early in the morning.    

Some members of the public are so attached to the narrative or the "Stonehenge belief system" that they actually feel that any criticism or questioning of it is equivalent to an attack upon themselves.  Comments that fly about on social media suggest that some actually feel personally wounded.  On a couple of occasions on Twitter, when I have questioned some of the "astonishing discoveries" made by certain Stonehenge experts, and the post-processual methods employed in British archaeology, there has been a furious response from loose groups of individuals who seem to think I have been attacking, demeaning or patronising them personally.  It's really rather bizarre -- until one realises that large groups of people spend much of their time flagging up and blowing the trumpet for the latest Stonehenge discoveries, retweeting messages, congratulating the archaeologists involved and generally getting a nice rosy glow from the whole process.  They are the members of an informal club, obtaining some sort of personal validation and pleasure from these social media interactions.   And I can understand that, as a member of my own little Facebook group!

But when somebody comes along and says "Hang on a minute!  Has anybody actually read this particular article and scrutunized the evidence?  Has it occurred to you that this might all be much ado about nothing?" they feel personally threatened, and out come their daggers in self-defence..........

And there is another level too, involving an archaeological establishment which protects itself, and its senior members who promote one Stonehenge "astonishing discovery" after another, by making sure that mavericks are given short shrift.  Poor Geoffrey Kellaway discovered that many years ago, when he had the effrontery to question the bluestone "human transport" myth and was dealt with on the telly by an assortment of thugs in dark suits.  And similar things have happened since, generally behind the scenes, as some who may read this post will know to their cost.

Some of the blame for the current situation rests with media outlets who are obsessed with Stonehenge, as Kenny Brophy points out.  And those who manage and promote Stonehenge may or may not be aware of the social and psychological impact of their high pressure marketing campaigns, but when a powerful myth is adopted by a cult, the results are not always benign.