Garn Turne excavation report

Adam Stanford's photo of the Garn Turne excavation 2012.   If you can't read the annotations, the large rock in the foreground is the Foss Stone, the one on which the diggers are sitting is GT Major, and the big one to the right of that is GT Minor.

This is an interesting excavation report (as required by RAI funding) describing the history of the "megalithic" occupation of this site.  I remain sceptical about all this "quarrying and moving" stuff, since it seems to me that the large stones have effectively been used where they were found, having been levered up to allow their use as cap-stones.  That does not, it seems to me, entitle the archaeologists to use the word "quarrying."  There is also reference to the big capstone having been quarried and "flaked into shape" through the use of "massive hammerstones"........  How big can hammerstones be before they become too heavy to manage?  Not very big, I suggest...... unless the Neolithics were mighty powerful muscular specimens of manhood.  30 cms in diameter?  About 15 kg? Does anybody know of hammerstones heavier than this actually being used?

And what's the evidence for the flaking or shaping of the big capstone reputed to weigh 80 tonnes?

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Building the Great Dolmens: Excavations at Garn Turne, Pembrokeshire
Vicki Cummings and Colin Richards
http://www.royalarchinst.org/sites/royalarchinst.org/files/Newsletter_47.pdf

Our second season at Garn Turne (GT) has
revealed multi-phase activity at this extra ordinary
site, including remains of at least two dolmen
monuments. There had appeared to be a natural
outcrop in the middle of the forecourt, unpar -
alleled at other dolmen sites in Britain or Ireland.
Excavations revealed that this is not an outcrop but
a quarried stone — the Floss Stone — sitting on
the edge of a pit, probably its source, which had
evidence of intense burning in one area. It was also
partly set on a rammed-stone platform, cut by the
digging of a large pit (probably the pit for the main
capstone at the site) so we know that its quarrying
and moving predates the main dolmen (GT
Major).

Also pre-dating it are remains of a smaller
dolmen (GT Minor) directly to north-west of the
main site. Before excavation only the capstone was
visible above ground. In our trenches, though, we
found collapsed orthostats alongside the large
prostrate capstone. This monument once stood in
a large pit, much like Arthur’s Stone on the Gower.
At a later date, and once the monument had col -
lapsed, the dolmen was surrounded by a platform
of stones and soil so that the pit and collapsed
uprights were no longer visible. We were able to
explore this dolmen in only one small area because
after construction of the platform, smaller stand -
ing stones were added around the collapsed cap -
stone.

The main monument (GT Major) was con -
structed after both the quarrying of the Floss Stone
and the construction of GT Minor. A large pit in
the forecourt was almost certainly the original
location of the 80-tonne capstone for GT Major. It
was quarried, flaked into shape using massive
hammer stones, and the pit from where it was dug
partly backfilled. It was then elevated onto its
supporting uprights, before collapsing, presum -
ably due to sheer weight. Later, a forecourt of sorts
was constructed, partly in the remains of the
massive quarry pit. We also identified a series of
standing stones nearby, demonstrating that this
entire landscape had seen monumental construc -
tion.