Dacites and the fictional orthostat

 Ixer and Bevins keep on publishing at a furious rate in conjunction with assorted colleagues-- I am not sure what the beloved WANHM magazine would do without them! The latest article is entitled "Stonehenge Dacite Group D -- fact or fiction?". WANHM Vol 115, pp xx - xx. Strange title, since if the group is a fiction it is fiction of their own inventing. It's like putting up an Aunt Sally in order to have the satisfaction of knocking it down.......

Anyway, the article is available via Academia for those who want to check it out.

We are all (and that includes the authors of this latest piece) confused by the sheer abundance of fragments (the authors never differentiate between "fragments" and pebbles or stones) of widely differing lithologies scattered across the Stonehenge landscape.  Most geologists, in their shoes, would have long since abandoned the very idea of bluestone quarries, since both monoliths and fragments are so hugely variable in their characteristics that they must have come from multiple locations in West Wales and further afield. But they insist on seeking to gather their samples into groups in an attempt to minimise the number of "provenences" because that is the only way they can maintain the human transport hypothesis;  it makes no sense at all for Neolithic tribesment to have wandered all over West West collecting up stones from here, there and everywhere just to cart them off to Stonehenge and then throw them away or break them up.

Anyway, here we go again, with 8 rather inconvenient fragments analysed and found not to match up with anything in particular.  They do seem to match with one another.  The authors do not know where they came from, and assume (without any foundation) that they must have come from a missing orthostat, and that they have most probably come from North Pembrokeshire.   They also consider that the fragmants are "true bluestones", whatever that may mean.

For the sake of completeness, here is the latest classification:

Hmmm -- just as we were getting used to Volcanic Group B, it's disappeared into thin air, to be replaced by Dacite Group B.  Whatever next?

In their conclusion the authors do consider the possibility that the unassigned dacite fragments might have been introduced to the area as glacial erratics, but they dismiss that option on the grounds that no other "unequivocal" glacial erratic has ever been found in the Stonehenge landscape.  One might ask: "What about all those bluestone boulders that make up the bluestone circle?"  And one might also ask: "What about Newall's ignimbrite boulder?"  Of which more anon.

And who gets to decide what is equivocal and what is unequivocal?  Are the famous bluestone quarries "unequivocal"?   Is MPP's "lost circle" unequivocal"?  Ixer and his friends may think so, but there are very many of us who beg to differ.