"If ice carried bluestones from west Wales to the Stonehenge neighbourhood, why are there no other bits of bluestone debris anywhere else besides Stonehenge?"
Well, Olwen Williams-Thorpe and her colleagues itemised abundant known occurrences more than 20 years ago, and if you want some info from a senior archaeologist, perhaps Tim Darvill will do.
Here is an extract:
Everybody Must Get Stones
Timothy Darvill
Timothy Darvill
in
Internet Archaeology, Issue 26 (2009). Implement Petrology theme
URL: http://intarch.ac.uk/journal/issue26/6/4.html May 27 2009
Internet Archaeology, Issue 26 (2009). Implement Petrology theme
URL: http://intarch.ac.uk/journal/issue26/6/4.html May 27 2009
..............there are numerous flakes and chips in what has become known as the Stonehenge Layer right across the interior of the monument (Atkinson 1979, 63-4). Colonel Hawley was astonished to find that bluestone fragments exceeded sarsen by a factor of four to one in the areas he sampled between 1921 and 1926 (Hawley 1921; 1922; 1923; 1924; 1925, 21-2; 1926; 1928). A piece of spotted dolerite was found in the ditch of the Heelstone in 1979, perhaps part of a shaped monolith (Pitts 1982, fig. 25), and more than a dozen pieces of bluestone have been found in the surrounding landscape (see Stone 1948; 1950; Pitts 1982, 125-6; and Thorpe et al. 1991 for lists). Deliberate placement of bluestone chips and fragments with burials, perhaps to help sustain life, are recorded with the Beaker burial in the ditch at Stonehenge and nearby at Amesbury 4 (Engleheart 1932) and Amesbury 51 (Ashbee 1978), while unstratified pieces have been found at three local round barrows: Winterbourne Stoke 28 (Cunnington 1929, 226), Winterbourne Stoke 29 (Cunnington 1884, 143), and Wilsford 35-36e (Hoare 1812, 206).
Beyond the Stonehenge Landscape there are pieces of bluestone scattered across central southern England and these are often assumed to have come direct from the Preseli Hills as part of the 'axe-trade'. In fact most can be more economically explained as souvenirs from the break-up of Stonehenge. The large fragment found by William Cunnington inside the long barrow known as Boles Barrow some 19km to the north-west of Stonehenge is often cited as evidence for the early arrival of spotted dolerite in Wiltshire. As I have argued elsewhere, however, this piece most likely lay within a deliberate blocking deposit within the chamber, a practice common across Britain in the late third millennium cal BC and wholly consistent with the early destruction of Stonehenge (Darvill 2006, 126). The same might apply to the fragment of Group XIII stone in the upper fill of Middle Ditch segment IB at Windmill Hill, which was described by Isobel Smith as 'difficult to interpret as part of an axe' (1979, 19; see also Smith 1965, 114 and Whittle et al. 1999, 340). A piece of rhyolite similar to that in the Bluestone Circle at Stonehenge was found on the top of Silbury Hill during excavations in 1969 (Atkinson 1970, 314; Whittle 1997, 21), and a piece of spotted dolerite found near the West Kennet long barrow (Williams-Thorpe et al. 2004, 373) was perhaps lost en route to the ceremonies that must have accompanied the filling of the chamber at this well-known barrow.
Beyond the Stonehenge Landscape there are pieces of bluestone scattered across central southern England and these are often assumed to have come direct from the Preseli Hills as part of the 'axe-trade'. In fact most can be more economically explained as souvenirs from the break-up of Stonehenge. The large fragment found by William Cunnington inside the long barrow known as Boles Barrow some 19km to the north-west of Stonehenge is often cited as evidence for the early arrival of spotted dolerite in Wiltshire. As I have argued elsewhere, however, this piece most likely lay within a deliberate blocking deposit within the chamber, a practice common across Britain in the late third millennium cal BC and wholly consistent with the early destruction of Stonehenge (Darvill 2006, 126). The same might apply to the fragment of Group XIII stone in the upper fill of Middle Ditch segment IB at Windmill Hill, which was described by Isobel Smith as 'difficult to interpret as part of an axe' (1979, 19; see also Smith 1965, 114 and Whittle et al. 1999, 340). A piece of rhyolite similar to that in the Bluestone Circle at Stonehenge was found on the top of Silbury Hill during excavations in 1969 (Atkinson 1970, 314; Whittle 1997, 21), and a piece of spotted dolerite found near the West Kennet long barrow (Williams-Thorpe et al. 2004, 373) was perhaps lost en route to the ceremonies that must have accompanied the filling of the chamber at this well-known barrow.
Of course, in the above extract the assumption that all bluestone bits and pieces were transported by humans is adhered to with almost religious conviction by Tim, but no evidence of any kind is brought forward to contradict the hypothesis that many if not all of these fragments were present in the Stonehenge landscape -- and further afield -- well before the Neolithic, and that glacier ice may well have had something to do with it.
