www.Sarsen.org
A Contrarian’s Obsessive Guide to Stonehenge’s Latest Research
Wednesday, 15 October 2025
New Experimental Study Sheds Light on Prehistoric Sarsen Working Techniques at Stonehenge
Using a single 54kg block of saccharoidal sarsen, Harding tested the processes of splitting, flaking, and pecking through controlled experiments. Hammers comparable to prehistoric tools—including flint and quartzite examples, a ball pein hammer, and a 3kg sledgehammer—were employed to assess fracture mechanics and the effects of heat. The results show that repeated, accurate blows using direct percussion could progressively open controlled fractures, adapting methods familiar from flint knapping. Flaking produced broad trimming flakes but proved “unsuited for thinning or shaping monoliths,” while peck dressing, though effective, was laborious and slow. Heating the stone to around 400°C offered no advantage, and higher temperatures “shatter the structure of sarsen, rendering it unworkable.”
The findings suggest that controlled splitting by percussion was the principal technique for reducing large sarsen blocks, with flaking and pecking serving more limited roles in finishing surfaces. Harding concludes that while the experiments cannot “comprehensively resolve the complex technological challenges linked to this stone,” they “reawaken understanding and appreciation of the potential provided by direct percussion” and “admiration for the skill and persistence of the prehistoric workers in the process.” Together, these results strengthen the case that Neolithic builders of Stonehenge relied on carefully applied shock and precision rather than wedges or heat to master the “unbreakable” stone.
Harding, P. (2025) ‘DEMYSTIFYING SARSEN: BREAKING THE UNBREAKABLE’, The Antiquaries Journal, pp. 1–21. doi:10.1017/S0003581525100309.
Tuesday, 14 October 2025
Castilly Henge Update
Since my visit and post about the excavations at Castilly Henge the dig has been concluded and the results and finds are being analysed.
The dating results of the henge bank and ditch have not been revealed yet but the key question whether there is evidence of the remains of a now-removed stone circle at the centre of the henge has some answers.
Dr Olaf Bayer, Historic England’s Senior Archaeological Investigator and Nicola Hembrey, Historic England Archaeological Excavation Principal at the Castilly Henge excavation. © Historic England. Image reference DP572335. Click to enlarge
Correcting the Record on Cunnington's Rock Samples and Slides
Ah, the latest dispatch from the front lines of Stonehenge petrology: Robert Ixer's and Richard Bevins's catalogue of William Cunnington's Victorian-era thin sections and hand specimens, now gracing Academia.edu like a long-lost gem from Devizes. For those not in the weeds, this is a meticulous archive of 33 slides and their parent rocks from Cunnington's haul of 460 "foreign rock" fragments, scooped up between 1878 and 1881 from turf scrapes, wagon ruts, barrows, and even a few cheeky digs inside the circle itself. Sarsens? Wisely binned, as we're chasing the bluestones' secrets here. As inevitable as the Ancient Mariner waylaying yet another wedding guest with his watery woes, Brian John has slunk back to cast his jaundiced eye over the catalogue. John gets this bit spot-on in his review, bless him—it's a tidy summary of the collection's scope and its unbiased charm as a snapshot of surface debitage. Credit where due: he even flags the pyrite/marcasite oddity (unanalysed, alas) and the general lithological lineup, which does indeed mirror other collections in its "correct" proportions. One might almost think he's read the thing.
But then, inevitably, Brian John lurches into his familiar refrain, that weary old dirge about the "limited range of rock types" being a "tired old point" peddled by Ixer and Bevins to prop up their human-transport heresy. Oh, Brian—it's like watching a man clutch at straws in a gale, insisting the wind's just a myth because he hasn't dug up every sodden acre of Salisbury Plain. Yes, the catalogue quotes it proudly: all major groups (spotted dolerites, Rhyolite C, Andesite A, and the rest) tally up nicely, debunking the notion of "random glacial erratics" with a polite but firm wave of obsolete nomenclature. John concedes the proportions are "comparable," yet sneers that the duo have "over and again demonstrated... outliers and exceptions" in their own work, proving "multiple provenances." How deliciously selective! Those "outliers"—like the rare Dacite Group D in S57, now elevated to genuine bluestone status via Aubrey Hole finds, or the Greensand in S61—are precisely what the catalogue folds in with scholarly grace, not the chaotic scatter John dreams of for his ice-age fantasy. And his parting shot? That 50% of the monument's turf remains unexcavated, rendering all claims "very unwise"? Pure vapour—hand-wringing from a chap whose glacial hobbyhorse has been lamed by a generation of sediment cores, till fabrics, and isotopic dead-ends. It's not unwise; it's science, Brian. Do try keeping up.
Take the seven rhyolitic tuffs, all neatly slotted into Rhyolite Group C from Craig Rhos-y-felin, complete with their Jovian, Snowflake, and Zebra textures. John, ever the contrarian, brands this "wishful thinking rather than science," scoffing that Harrison et al. (1979) saw a "range" the authors blithely ignore. "No way that this claim can be accepted," he thunders. How droll—like a flat-Earther mocking satellite photos because they don't show the ice wall. The catalogue doesn't ignore Harrison; it updates him, with tight petrography (titanite clusters, chlorite infills, the lot) tying every variant back to Rhos-y-felin's outcrop. John's "pretence" jibe? That's the projection talking, a last gasp from a theory as threadbare as his patience for peer review. Fair play, though: he does nod to the appendices' "useful photos" and full descriptions—small mercies in the bile.
Then there's Table 1, that paragon of evolutionary nomenclature, tracing Cunnington's "Diabase" through Teall's ophitic musings to modern precision. John spies "clear evidence of 'forcing' lithologically different samples into predetermined groups," with some appendices showing "reasonable 'fits'" and others... well, not so much. Evidence? One might ask for a microscope, but no—it's all in the eye of the glacial beholder. Borderline calls like S74 ("volcanic with sub-planar texture," covering "a multitude of sins") or S57's anomalous Dacite D get flagged transparently as "ODD" or provisional, with calls for re-sectioning in the "Further Work" bit. No forcing here, just rigour; John's conspiracy of categories crumbles under its own weight. He scores a point on S52's heft (over 74g, cobble or chip?), rightly noting the orthostat ambiguity the authors "traditionally ignore." Touché—though the catalogue matches slides to specimens with forensic care, including fresh orthostat firsts like Stones 32c and 61a. Progress, Brian; it's unbecoming to sulk.
The Lower Palaeozoic sandstones fare better in his crosshairs: S1's hefty lump (500g, five pieces) from Barrow 41 (or 42—labelling's a muddle, as admitted), a mile off, and S69's broad-brush tag encompassing "many thousands of different lithologies." Spot-on reportage, and a reminder of these as the heavy hitters among non-dolerites (cf. that 8.5kg Roman shaft beast). But John's "S74... multitude of sins" and Greensand "inconvenien[ces]"? Derisory twaddle—these are the very anomalies that enrich the tale, not torpedo it, with S61's glauconite and foraminifera screaming local Cretaceous, not Welsh wanderlust.
And lo, the Altar Stone in Appendix 6—S45's dusky yellow, carbonate-cemented glory, with its limonite stains, stylolites, and that tantalising garnet in the heavy minerals. John quotes the microscopical description verbatim (muscovite laths, twinned plagioclase, the works), and even flags the "garnet problem" and Wilts 277's murky slide origins via his blogs. Hats off: this is John at his best, distilling the specialist stuff without the snark, nodding to the Scottish provenance buzz (Clarke et al., 2024) and prior harmonies (Ixer & Turner, 2006, et al.). It's a crumb he earns, linking micaceous debitage to Cunnington's own hunch.
In the end, John's review is a curate's egg: the shell's cracked with envy, but the yolk—those factual nuggets—nourishes. Yet it's vinegar strokes all the way down, a lonely obsession flogging a discredited glacial nag long after the field's moved on to quarries and causeways. Ixer and Bevins don't "fail to see the obvious"—they chase it with data, not daydreams. Multiple provenances? Aye, but sacred Welsh ones, not a slurry of ice-rafted odds and sods. The exceptions scream intentional transport, not random dump; John's "obvious conclusion" is the mirage he mistakes for an oasis. Welcome addition indeed—this catalogue polishes another facet of Stonehenge's human story, outliers and all. Brian, old chap, time to thaw that theory out for good.
Saturday, 11 October 2025
Charity Run from Preseli to Stonehenge
https://www.justgiving.com/page/alex-bance-10
A Salisbury runner is retracing the journey of Stonehenge’s stones in a 300-mile charity challenge for Julia’s House Children’s Hospice.
Alex Bance, 45, set off from the Preseli Hills in west Wales, where the monument’s bluestones were quarried. Along the route — which passes via West Woods near Marlborough, the source of the sarsen stones — he plans to gather small stones from key locations and carry them to the ancient site. Bance will take brief 20-minute naps during the run and has already raised more than £1,800 to support the Wiltshire and Dorset hospice.
Tracker - https://track.trail.live/event/path-of-the-past
Social Media - http://www.facebook.com/spireinjuryclinic
http://instagram.com/spireinjuryclinic
Wednesday, 8 October 2025
Stonehenge and Avebury Setting Study - Approved by Cabinet
Wiltshire Council's Cabinet approves plan to help mitigate the potential impact of development on Stonehenge and Avebury World Heritage Site
Stonehenge and Avebury WHS Setting Study SPD - Draft for adoption
Supporting documents:
- StonehengeandAveburyWHSSettingStudySPD_251007 , item 19.PDF 166 KB
- WHSSettingStudyAppendix1_251007 , item 19.PDF 2 MB
- Stonehenge and Avebury SPD 15.09.2025 c , item 19.PDF 17 MB
Decision:
Resolved:
That Cabinet:
1. notes the response to the consultation on the draft WHS Setting Study Supplementary Planning Document (the Setting Study) set out in the Consultation Statement at Appendix 1.
2. endorses the amended Setting Study as set out in Appendix 2.
That Cabinet recommends that Council:
3. Adopts the Setting Study (Appendix 2) to Council as a supplementary planning document at its meeting on 21 October 2025.
4. Delegates to the Corporate Director, Place, in consultation with the Cabinet Member for Strategic Planning, Development Management and Housing, the authority to undertake the final stages associated with the formal adoption and publication of the Setting Study, including any minor textual changes in the interests of clarity and accuracy.
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A summary of the Consultation concerns and responses:
Statutory/Advisory Bodies
Historic England
UNESCO World Heritage Centre/ICOMOS
Natural England
National Highways
Local Interest Groups
Druid Groups
CPRE South Wilts
Cycling Opportunities Group for Salisbury
Avebury Society
Wiltshire Archaeological & NH Society
Stonehenge Alliance
Town and Parish Councils
Amesbury Town Council
Marlborough Town Council
Preshute Parish Council
Developers/Consultants
General (two developers/planning consultants)
Members of the Public
General (varied comments)
Farmers/Landowners
General
Overall Summary
- Consultation responses welcomed; amendments enhanced clarity/precision without altering substance.
- Key partners (e.g., National Trust, English Heritage) pre-consulted, no further input needed.
- Final SPD strengthened for better planning assessments near WHS.
The Catalogue of the Wessex Museum Stonehenge Rock Thin Sections
William Cunnington Stonehenge rock thin sections - Catalogue
Rob Ixer and Richard Bevins
https://www.academia.edu/144337293/Cunningtons_Stonehenge_rocks_an_archive_of_the_thin_section_data
This catalogue, compiled by Rob Ixer and Richard Bevins in February 2025, documents 33 Victorian-era thin sections of Stonehenge rock fragments collected by William Cunnington between 1878 and 1881. These samples, primarily surface finds from within the Stonehenge circle and nearby excavations, represent an unbiased assortment of 'foreign rocks' (bluestones), excluding sarsens, and include the last known surface fragments from the monument's interior. The authors pair the thin sections—housed at the Wiltshire Museum—with corresponding hand specimens at the Salisbury Museum, providing macroscopic and microscopic petrographic descriptions. Historical identifications from researchers like Thomas Davies in Cunnington (1884), J.J.H. Teall (1894), and John Judd (1903), alongside later work by A.C. Harrison et al. (1979), are reconciled with modern nomenclature from Ixer and Bevins' ongoing studies (2010–2024). This reveals strong consistency in lithological groupings, such as spotted dolerites, rhyolitic tuffs from Craig Rhos-y-felin, and carbonate-bearing andesites, while debunking outdated names that have exaggerated the diversity of bluestone types to support glacial erratic theories. The collection's representativeness allows direct comparison with other Stonehenge debitage assemblages, affirming a restricted suite of Welsh-sourced volcanics and sandstones and the Scottish Altar Stone.
The detailed analyses in the appendices cover eight dolerites (including first petrographic descriptions of orthostats SH32 and SH61a), seven Rhyolite Group C tuffs, five Andesite Group A samples (with SH32c as type material), six Dacite Group B tuffs (type from SH38), one each of Dacite Group D, Altar Stone sandstone, and Greensand, plus three Lower Palaeozoic Sandstones. No novel rock types emerge, but the work highlights challenges like slide thickness and discolouration, which complicate observations. Appendices provide exhaustive microscopic descriptions, noting alterations (e.g., epidotisation, chloritisation) and key minerals (e.g., clinopyroxene, plagioclase, titanite). The authors advocate re-preparing polished thin sections for rarer lithologies and undescribed orthostats to enable advanced techniques like automated mineralogy.
Key Takeaways
- Representativeness and Consistency: The Cunnington collection mirrors other bluestone debitage from the Stonehenge landscape, comprising a narrow range of lithologies (e.g., dolerites, rhyolites, andesites, sandstones), reinforcing human transport from Wales over glacial deposition models.
- Nomenclature Updates: Modern reclassifications eliminate obsolete terms, clarifying that the bluestone suite is far less diverse than previously suggested, with most of the rhyolites tracing to Craig Rhos-y-felin and dacites distinguishing clearly in thin section.
- New Insights on Orthostats: First-time petrographic data for stones SH32, SH32c (type for Andesite Group A), SH49, and SH61a, plus expanded recognition of Dacite Group B debitage from SH38, potentially indicating wider distribution.
- Validation of Rare Groups: Confirms Dacite Group D as a legitimate bluestone lithology, based on this and prior finds, challenging its prior dismissal as non-monumental.
- Recommendations for Future Work: Re-sectioning key samples for polished slides is urged to support geochemical and mineralogical provenance studies.
Tuesday, 7 October 2025
Review: Bluestone Fragments at Silbury Hill – Resolving Provenance and Prehistoric Significance
(Dolerite Chip in the
Alexander Keiller Museum - Tim Daw)
The discovery of Stonehenge bluestone fragments from the top
of Silbury Hill has provoked enduring debate, amid stratigraphic and
petrological ambiguities. In the latest WANHM, Wiltshire Archaeological and
Natural History Magazine, Ixer, Bevins, and Pollard (2025), https://www.academia.edu/144003051/Slbury_Hill_lithics
, provide a meticulous reappraisal,
synthesising archival data with advanced microscopy to affirm these as
deliberate human-transported debitage. A pivotal contribution lies in
clarifying the corpus's fraught discovery history, particularly the discrepancy
between Atkinson's published account—mentioning only a volcanic tuff—and the
separate archival identification of a spotted dolerite via a museum label, a
mismatch that has long muddled interpretations.
Five fragments comprise the corpus: four flaked spotted
dolerites ('preselite') and one volcanic tuff (initially termed 'volcanic
ash'). Atkinson's 1970 Antiquity note records just one find from an
"undisturbed" summit context: the tuff fragment (Wilts 391),
macroscopically identified as akin to Stonehenge's volcanic ash bluestone and
recovered from clean chalk rubble ~0.7 m below the surface (Atkinson 1970,
314). Its pairing with a 'Windmill Hill ware' sherd—later deemed likely
Anglo-Saxon—hinted at disturbance, undermining claims of Neolithic integrity.
Unmentioned in Atkinson’s account but documented via a bag label in the
Alexander Keiller Museum archive, is a second fragment from the 1969 topsoil: a
spotted dolerite specimen. Three additional spotted dolerites surfaced from
2007 subsoil excavations, all lacking secure prehistoric associations (Ixer
2013). This selective reporting—overlooking the labelled dolerite—has sown
confusion, with the tuff often conflated with the dolerite or dismissed as
intrusive, as noted in subsequent syntheses (Field & Leary 2010, 60–61).
Post-excavation analyses amplified uncertainties. Wilts 391,
the thin section derived from Atkinson's tuff fragment and prepared in the
1970s for the South West Implement Petrology Collection, was erroneously
identified by R. V. Davis as Cornish hornblende schist, emphasising 'decomposed
feldspar' (misread sparry calcite) while disregarding its clastic tuff fabric
and Atkinson's macroscopic assessment (Clough & Cummins 1988, 162). The
original rock specimen vanished, likely consumed in sectioning, prompting
further conflations. Such lapses, compounded by incomplete documentation,
invited speculation of post-Neolithic intrusion—via antiquarian activity or
medieval remodelling (Field & Leary 2010, 60–61).
Ixer et al. (2025) disentangles this 'conundrum' through
rigorous petrography, confirming all five as Stonehenge-sourced debitage and
explicitly resolving the Atkinson-label disconnect by cross-referencing museum
records with fieldwork archives. Wilts 391 exemplifies calcite-bearing Andesite
Group A tuff, with limonite-stained 'rhyolite' clasts (fine-grained white
mica-albite-chlorite-quartz intergrowths), vesicular lava inclusions, and
tension gashes—hallmarks matching buried orthostat 32c from north Pembrokeshire's
Fishguard Volcanic Group (Ixer et al. 2023). The dolerites, including the
labelled 'Museum' piece, exhibit ophitic textures, epidotisation, and spinel
spots diagnostic of 'preselite'. This validates Atkinson's intuition while
exposing Davis's oversights, attributing the sherd to localised disturbance
rather than wholesale rejection of Neolithic deposition.
Crucially, the authors dismiss glacial transport—once
invoked for bluestone dissemination (e.g., Ixer 2009)—citing the flakes'
knapped morphology, sub-centimetre scale, and orthostat-specific matches, which
preclude Ice Age entrainment. Instead, they propose intentional Late Neolithic
conveyance and deposition during Silbury's final phases (~late 24th/early 23rd
century BC; Marshall et al. 2013), likely by Beaker-period groups effecting
ritual fragmentation. This echoes Darvill and Wainwright's (2009) model for
Stonehenge and parallels Cheviot granodiorite at West Kennet palisade (Ixer et
al. 2022), suggesting token exotics as apotropaic or mnemonic elements in a
networked monumental landscape (Richards et al. 2020).
As a review, Ixer et al. excels in transforming archival
detritus into interpretive clarity, elevating these four small dolerite chips
and single tuff flake to evidence of modest Wessex-wide mobility—chiefly by
demystifying the Atkinson-dolerite enigma. Whether the fragments derive from a
single larger piece or multiple orthostats remains unresolved, though their
petrological affinities suggest the four dolerite chips are all off one block.
Only Wilts 391 enjoys unambiguous Neolithic security, however, tempering
conclusions.
My own speculative thought experiment based on the overland
bluestone transport hypothesis positing an A40-aligned route from Preseli, with
a River Severn crossing near Gloucester (Parker Pearson et al. 2015) the
Avebury landscape lies on this natural route to Stonehenge. Are the chips from Stonehenge or souvenirs of a
passing monolith, maybe from initial shaping nearby?
References
Atkinson, R.J.C., 1970. Silbury Hill, 1969–70. Antiquity,
44, pp.313–314. Available at: https://doi.org/10.1017/S0003598X00104582
Clough, T.H.McK. & Cummins, W.A. (eds.), 1988. Stone
Axe Studies Volume 2: The petrology of prehistoric stone implements from the
British Isles. Council for British Archaeology Research Report 67, London.
ISBN: 0-906780-52-7. Available at: https://www.cambridge.org/core/journals/antiquity/article/reviews-t-h-mck-clough-w-a-cummins-ed-stone-axe-studies-2-the-petrology-of-prehistoric-stone-implements-from-the-british-isles-279-pages-42-figures-240-tables-3-maps-1988-london-council-for-british-archaeology-research-report-67-isbn-0906780527-paperback-35/4D955A236D2703A06740E01B2E4C44AE
Darvill, T. & Wainwright, G., 2009. Stonehenge
excavations 2008. The Antiquaries Journal, 89, pp.1–19. DOI:
10.1017/S000358150900002x. Available at: https://eprints.bournemouth.ac.uk/11797/
Field, D. & Leary, J., 2010. The Story of
Silbury Hill. English Heritage, Swindon. ISBN: 9781848020467. Available
at: https://books.google.nl/books/about/The_Story_of_Silbury_Hill.html
Ixer, R.A., 2013. The spotted dolerite fragments. In: Leary,
J., Field, D., & Campbell, G. (eds.) Silbury Hill: the largest
prehistoric mound in Europe, pp.60–61. English Heritage, Swindon.
Ixer, R.A., Bevins, R.E., Pirrie, D. & Power, M., 2023.
Treasures in the Attic: Testing Cunnington's assertion that Stone 32c is the
‘type’ sample for Andesite Group A. Wiltshire Archaeological and
Natural History Magazine, 116, pp.40–52. https://pure.southwales.ac.uk/en/publications/treasures-in-the-attic-testing-cunningtons-assertion-that-stone-3
Ixer, R, Bevins, R, Pearce, N, Pirrie, D, Pollard, J,
Finlay, A, Power, M & Patience, I 2025, 'Exotic granodiorite lithics from
Structure 5 at West Kennet, Avebury World Heritage Site, Wiltshire, UK', Wiltshire
Archaeological and Natural History Magazine, vol. 118, pp. 1-18. Available
at: https://www.academia.edu/125773662/West_Kennet_Granodiorites [
Ixer, R.A., Bevins, R.E. & Pollard, J., 2025. Bluestones
from Silbury Hill. Wiltshire Archaeological & Natural History
Magazine, 118, pp.269–278. Available at: https://www.academia.edu/144003051/Slbury_Hill_lithics
Marshall, P., Bayliss, A., Leary, J., Pollard, J.,
Vallender, J. & Young, G., 2013. The Silbury chronology. In: Leary, J.,
Field, D. & Campbell, G. (eds.), Silbury Hill: the largest
prehistoric mound in Europe, pp.97–116. English Heritage, Swindon.
Parker Pearson, M. et al. (2015) ‘Craig
Rhos-y-felin: a Welsh bluestone megalith quarry for Stonehenge’, Antiquity,
89(348), pp. 1331–1352. https://www.cambridge.org/core/journals/antiquity/article/craig-rhosyfelin-a-welsh-bluestone-megalith-quarry-for-stonehenge/D1E66A287D494205D22881CBF1F6DDE8
.
Richards, C., Bayliss, A., Beadsmoore, L., Bronk Ramsey, C.,
Card, N., Dunbar, E., et al., 2009. The date of the Greater Stonehenge
Cursus. Antiquity, 83(319): pp.40–53. DOI:
10.1017/S0003598X00099363. Available at: https://www.researchgate.net/publication/233882913_The_Date_of_the_Greater_Stonehenge_Cursus