Mike Pitts on the Bluestones

Below I have pasted the article which is causing a great hullaballoo (how does one spell that word?) in archaeological circles. It was written by the Editor of British Archaeology. Mike Pitts, and was based in part of information provided by geologists Rob Ixer and Richard Bevins. Sadly, like all "popular" articles, it contains inaccuracies. Jim Scourse and Chris Green are geomorphologists, not geologists. Geoff Kellaway's Christian name is Geoffrey, not George. The "shift" of the key spotted dolerite location from Carnmeini (Carnmenyn) to Carngoedog is not new -- this was proposed long ago by the OU team which published its big report on the bluestones in 1991. And I will beg to differ with whoever said that the problem of how the stones were moved from their source areas to their locations on Salisbury Plain is "an archaeological problem." From where I stand, this is a problem that needs to be sorted by geomorphologists, glaciologists and geologists -- and this is increasingly apparent from the new evidence of multiple sources and multiple lithologies being represented in the bluestone assemblage of Salisbury Plain.

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Missing Stonehenge circle did not come from Preselis
British Archaeology
November December 2009|7

A new theory about the Stonehenge
bluestones is set to divide geologists
and archaeologists, and open new
inquiries into how and why the famous
stones reached Stonehenge.
The site’s megaliths are traditionally
classed into two groups, sarsens (a local
sandstone) and bluestones. While the
former, at an estimated total weight of
1,700–1,800 tonnes, outscale the 250-
odd tonnes of the latter, the bluestones
have dominated debate. The issues of
where they came from and how they
reached Stonehenge, have polarised
into two widely divergent views:

•Most derive from the Preseli Hills
in Pembrokeshire, south-east Wales,
and were taken to Wiltshire by the
builders of Stonehenge around
3000–2500bc

•Alternatively, they come from a
variety of sources in south Wales, and
reached Salisbury Plain as glacial
erratics during the ice age, thousands of
years before Stonehenge was built.

Most prehistorians believe people
moved the stones. This was what
geologist Herbert Thomas proposed,
when he first identified the Preselis as
the origin in 1920: a view endorsed by
geologists including Christopher
Green and James Scourse, and recently
by archaeologists Timothy Darvill and
Geoffrey Wainwright, who claim to
have found quarry outcrops and “sacred
springs” at the source of the megaliths
around Carnmenyn.

Geologist George Kellaway
proposed in 1971, by contrast, that the
bluestones had been transported by a
glacier. This view has been supported
by archaeologist Aubrey Burl, and (in a
differing glacial interpretation) an
Open University team of geologists
including Olwen Williams-Thorpe.
Last year the latter wrote on a BBC
Timewatch blog that the bluestones
“are a rag-bag mix… from all over south
Wales”, and Brian John published The
Bluestone Enigma (see Books, page 55).

Now geologists Rob Ixer (University
of Leicester) and Richard Bevins
(National Museum of Wales) are
proposing a third option. They say
many bluestones came not from
Pembrokeshire, but from “a far wider
and, as yet, unrecognised area or more
likely areas” – perhaps north Wales
(Snowdonia, the Llyn Peninsula and
Anglesey), or even beyond. The wellknown
spotted dolerite, is a Preseli
rock, they say – but Carngoedog was
the likely source, not Carnmenyn.

These conclusions derive from a new
study of thousands of Stonehenge rock
specimens: from near the west end of
the Cursus earthwork (where a lost
bluestone circle has been proposed),
collected in 1947 and excavated by the
Stonehenge Riverside Project in
2006/08; and from Stonehenge,
excavated by Mike Pitts in 1979/80 and
Darvill and Wainwright in 2008.

The geologists also found the Cursus
bluestones, which are all rhyolitic and
mainly tuffaceous (with no Stonehenge
dolerites), had significant mineralogical
differences from visually similar rocks
at Stonehenge. The Darvill and
Wainwright excavation produced
significant amounts of a type of
rhyolite or rhyolitic tuff “not recorded
in north Pembrokeshire and noticeably
absent in the Mynydd Preseli area”.

How the stones were moved, Ixer
told British Archaeology, “is an
archaeological problem”, though he
wondered if “different groups [of
people] brought different stones?”
Ixer and Bevins’s detailed study will
be published in the 2009 Wiltshire
Studies. In WS 2006, Ixer and Peter
Turner suggested that the Stonehenge
Altar Stone (the largest bluestone)
came from an unidentified source far
from Milford Haven – the traditional
attribution said to indicate where the
Preseli stones were taken downriver
and out to sea by neolithic gangs.