Progress on the Meaden Cobble

The Meaden Cobble (below) alongside one of the quarried blocks from the Whatley Quarry.  Note the colour difference and the different angularity of edges.

Thanks to Paula and Martin, and thanks to the staff at the Whatley "super quarry", we now have some quarried rock samples to compare with the hand-sized sample found by Terence Meaden near West Kennet. The rock types in the quarry are quite variable:

Organic Dark Beds: The main body of the Black Rock Limestone exposed in the lower benches of the quarry is a deep, dark grey to near-black. This rich pigmentation is caused by a high concentration of organic material from ancient marine plants and algae, mixed with fine terrigenous muds. 

Extensive Top Dolomitisation: Unlike the cleaner, purely blue-black beds found elsewhere, the top of the Black Rock Limestone sequence at Whatley has undergone extensive dolomitisation. Magnesium-rich fluids altered the original limestone, resulting in highly weathered, earthy, brownish-black and buff-coloured zones.

The Angular Unconformity: Directly over the top of this dark, weathered Carboniferous sequence sits a flat, horizontally bedded layer of pale, sandy-buff Jurassic oolitic limestone. This forms a clear unconformity,  highlighting the dramatic boundary between the older, dark, muddy, steeply dipping limestone and the younger Mesozoic rocks. 

We have four dark-coloured samples of quarried rock, and all four of them have a bluish-black colour.  This looks slightly different from the brownish-black colour of the Meaden Cobble.  Because of the well preserved brachiopod imprint in the Meaden Cobble, it might have come from the muddy lower facies of the Black Rock Limestone.  This could have come from low in the Whatley Quarry sequence, or elsewhere in the Nunney valley area.  Other possibilities include Burrington Combe, Three Cliffs Bay and Caswell Bay in the Gower, and the "Zaphrentis" phase rocks around Linney Head. Freshwater West and elsewhere on the South Pembrokeshire Cliffs.

The Meaden Cobble (c 10 cm long) alongside another quarried block.  

The quarried block in this photo approximates more closely in colour to the Meaden Cobble

Crinoid fossils in one of the quarried blocks.

Because of the widespread nature of the Black Rock Limestone outcrops, I don't think we are going to get much closer to a good provenence, at least not for the time being. "Somewhere to the south-west or west" is maybe the best we can do.........

But having been looking again at the characteristics of the cobble, I am struck by the similarities with the infamous Newall Boulder.  There is a rough wedge or bullet shape, with a number of clear facets, a weathered surface patina and multiple sub-angular edges which are very different from those of the freshly quarried rocks from the Whatley Quarry. There are no angular or sharp edges -- wear is apparent everywhere on the surface of the stone.   As readers of this blog will know, I interpreted the surface characteristics of the Newall Boulder as demonstrating glacial transport, and I am convinced of that here too, in the case of the Meaden Cobble.    So -- another glacial erratic in an unexpected context.

If this cobble arrived in the vicinity of West Kennet in recent times as part of a load of roadstone, it would have sharp edges and very different surface characteristics.  As Terence has suggested, it might have moved downslope towards the footpath bit by bit, over many generations of ploughing, harrowing, planting and harvesting.  There are in fact many obvious scratch marks on the cobble surface, but only in one or two small instances have the scratch marks broken across the sub-angular facet edges.

So I am rather convinced, as in the case of the Newall Boulder, that this is a small glacial erratic.  It is not a fluvially transported cobble, or a piece of periglacial debris.  It is not a piece of crushed roadstone or a fragment directly derived from a quarry.  Neither is it a "knock-off" from an imported monolith or standing stone. Neither is it a "joint block" which owes nothing to the processes that operated during entrainment and transport from its source.

Once again the fanciful idea that "there are no glacial erratics on Salisbury Plain and adjoining areas" is directly contradicted by the evidence.

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See also this exchange which demonstrates all to clearly just how desperate the Parker Pearson team is to promote its fantastical bluestone transport narrative, come hell or high water:

Brian S John, 2026. The Newall boulder at Stonehenge: correcting the "corrections". Researchgate pre-publication document, 13 pp.
DOI:
10.13140/RG.2.2.10844.86401

The Newall boulder at Stonehenge: correcting the "corrections". Available from: https://www.researchgate.net/publication/399619799_The_Newall_boulder_at_Stonehenge_correcting_the_corrections[accessed Jan 10 2026].

.....................in response to this disgraceful ad hominem attack on my competence and integrity:

Richard E. Bevins, Nick J.G. Pearce, Rob A. Ixer, James Scourse, Tim Daw, Mike Parker Pearson, Mike Pitts, David Field, Duncan Pirrie, Ian Saunders, Matthew Power. 2025. The enigmatic ‘Newall boulder’ excavated at Stonehenge in 1924: New data and correcting the record, Journal of Archaeological Science: Reports, Volume 66, 105303.