10th Meeting of the Implement Petrology Group
held at the Oxford Archaeology North Offices in Lancaster
Vin Davis (Chairman); Tom Clare (Treasurer) Torben Ballin, Kate Barrs, C. Stephen Briggs, Jon Clatworthy, Gabriel Cooney, Frances Lynch (Minute Secretary), Mik Markham, Jamie Quartermaine, Alison Sheridan, Rosemary Stewart, Gill Varndell.
2. Apologies were received from
Steve Burrow (Secretary), Tim Darvill, David Dawson, Allison Fox, Mike Heyworth, Mark Edmonds, Dave Field, David Jenkins, Steve Mandall, Fiona Roe, Joan Taylor, Pete Topping, Dave Weddle, John Williams.
3. The Chairman welcomed Kate Barrs to the meeting.
She has a geology degree from Edinburgh and is currently working for an MA in Manx Studies in Douglas for which she is planning a dissertation which will update the Manx information on stone axes and concentrate on the late Neolithic Ronaldsway axes.
4. The Minutes of the Ballycastle meeting
Agreed to be an accurate record.
5. Matters arising from the Minutes
Prof Mark Edmonds was now working part-time in York and had concentrated his teaching into a limited period of the year to allow him to live and write in Orkney. This would mean that IPG could no longer use the King’s Manor for the Winter Meeting. It was suggested that we might hire the meeting room at the CBA’s York office instead. It was judged that the funds would allow this.
6. Chairman’s Report (Circulated in advance. Please read these Minutes in association with that document).
i. The Chairman tabled several off-prints of articles relating to implement petrology (listed in his written report), the publication Materialitas edited by Gabriel Cooney, and one or two other publications brought by members.
ii. He reviewed his written report and there was discussion of some of the points.
AHRC Grant Application. It was explained that this was a grant for work to revisit, and more, all the petrological data gathered since 1988 from the Irish Sea area using XPRF technology to attempt to resolve some remaining uncertainties. Alison Sheridan said that there might be a risk of overlap with the work being done by the SW Committee at the Camborne School of Mines, but it was thought that this could be resolved.
iii. IPC York Conference Proceedings. The editors were warmly congratulated on this internet publication.
iv. Stone Axe Studies III. This book would now be published by Oxbow at the cost of around £6,000 since Mark Edmonds would be doing the page-setting. It would be a hard back book, with colour. VD agreed to circulate the contents list with these Minutes (to follow); he said that the cost would probably be met from private donations and Prof Cooney offered to look for some grant aid from Ireland. It was hoped that it would be launched at the May meeting, and, if not, it would certainly be out by summer 2010.
v. St Buryan Hoard of 22 axe heads Gill Varndell said that further enquiry by the BM about these axes revealed that they were not a hoard, but a group purchased from a collector (at 3rd hand) in St Buryan.
7. Secretary’s Report
Steve Burrow had sent up examples of his initial work on the IPG website. As requested, members agreed the format. He invited members to provide some paragraphs (as indicated). The temporary address is www:steve.burrow.nameipg and the password is York. You will need to enter the details twice.
8. Treasurer’s Report
Tom Clare reported that there was £553 .00 in the bank and perhaps another £50 would be coming in from Standing Orders. The annual subscription was £5.00 but he wondered whether all the people (about 35) on the IPG e-mail list had been asked to subscribe. If all paid the annual income would be c. £175.00. It was agreed that a subscription reminder should be circulated.
9. Rosemary Stewart was doing a PhD at Reading looking at Mesolithic and Neolithic use of chert and hoping to differentiate regional sources and also to decide whether people were using chert from choice or necessity.
10. Torben Ballin had just published his work on Arran pitchstone and was now looking at baked mudstone from Skye and felsite from Shetland as well as Yorkshire flint from southern Scotland where he was working on identification criteria. Quartz waste found around cup and ring marked boulders was judged to be the remains of chisels used to create the art, rather than ritual deposits. He was concerned about over-optimistic identifications of pitchstone suggested by students working in Cumbria. Supervisors should be reminded that experienced professional advice could be obtained from IPG members.
11. Gabriel Cooney reported that the Irish Stone Axe Project was ready for publication once the Irish OS had agreed the use of townland identifiers. He mentioned the complexity of porcellanite distributions on Rathlin Island emerging from NMI work. Steve Briggs advised caution in relation to the Hewson Collection from Rathlin since many were likely to be recent fakes. Emmett O’Keefe was working for a PhD on the Mesolithic in the Irish Sea area and looking at stone axe heads in genuinely Mesolithic contexts.
12. Tom Clare was looking at the geology of the Cumbrian Stone Circles. He suggested that there was a need for a database of glacial erratics.
13. Gill Varndell reported that Vol 6 of the Grimes Graves series was due out soon. Future scholarly publications by the BM would be published electronically. She said that recent work on the BM building had meant that the reserve collections were very difficult to access but this situation was gradually being improved.
14. Steve Briggs said that he was currently working on the history of archaeological recording.
15. Jon Clatworthy of the Lapworth Museum said that they had recently received thin sections from Russell Coupe. This raised a general discussion on the matter of the thin section collections and the primary card record collections. Currently the thin sections were housed at the Lapworth Museum, Taunton Museum, the Department of Mineralogy at the Natural History Museum, National Museum of Scotland and National Museum of Wales or the Natural History Museum in London (according to the region from which the axes came) because of the provision of geological curation in these museums and the availability of petrological microscopes for enquirers. There was some discussion about whether Coupe’s Isle of Man material should go to Douglas, but there was not petrological microscope there. [Later in the meeting it was announced that the Open University was selling off small polarising microscopes for £200, which might help the Isle of Man situation]
The location of the primary card records was more uncertain. It was decided that IPG should write to all museums asking them whether they had any of these records. Alison Sheridan agreed to draft the letter and to consult with others about whom to send it to. It was suggested that the IPG website should list the location of the thin section collections and of the primary card collections when these were known.
16. Alison Sheridan said the Roy Ritchie archive was with the NMS, but that parts relating to Hunterian exhibits would be given back to the Hunterian. She said that the European Jade Project had been immensely stimulating and successful. The final publication was being prepared as 2 very large volumes and the Cardiff lecture would summarise its results. The BM’s History of the World series had included a jade axe; this had prompted previously unknown examples to be reported.
17. Any Other Business
Rosemary Stewart reported the sale of microscopes by the Open University (see above)
Jamie Quartermaine said that Rob Ixer had remarked on the lack of sufficient thin sections of potential source outcrops. In view of the variability of some bedrocks, especially in the Lake District, it was essential that the location of such samples be very precisely recorded. Earlier work of this kind had not been sufficiently precise.
A conference on European flint mining to be held in Budapest in August 2011 was announced.
18. Next Meeting
The summer field meeting is being organised by Vin Davis and Tim Darvill from May 6-9th Meeting 2010 in SW Wales. It may be based in Carmarthen to allow easier access to Cardiff for the Saturday May 8th Europa Lecture conference. The Sunday morning session will focus on glaciation and the potential use of secondary sources , led by Stephen Briggs). Would those intending to come please let Vin Davis know as soon as possible.
19 Presentations by members of Oxford Archaeology North
i. Gill Hey introduced the excavations which were reported on by Paul Clark and Mark Storey
Carlisle Northern Development Road site
ii. The site was on the west side of Carlisle on the edge of a river terrace above a bend in the River Eden and within an area of many old river channels. Attention was directed to the site because of the proximity of Hadrian’s Wall on the other side of the river and two hengiform monuments on the slopes above the development site.
ii. A very large quantity of Mesolithic flint, chert, quartz and tuff waste and microliths was discovered over a wide area (by automated sieving of 24,000 buckets of sand). Just to the west was a deep palaeo-channel containing beaver-chewed fallen wood. After this had filled, another channel was formed in the same place which contained more fallen trees (possibly cut by man). Among these were found 2 large oak tridents similar to those from Ehenside Tarn and one from Armagh. The use of these large, heavy blunt tridents was debateable. Dates for this channel were 38-36,000 cal BC. Four stone axes were also found in this early Neolithic channel.
iv. The axes, which were passed round for inspection, had been examined by Vin Davis and Mark Edmonds. Vin Davis provided the following information to the meeting:
v. Axe 70074.0077
Macroscopically, in thin section, the rock is olive grey 5Y 4/1.
Microscopically, the rock is quartz dolerite, which falls within the description for Group XVIII. This fine grained basic igneous rock is composed mainly of feldspar, augite and magnetite. The mainly colourless labradorite feldspar is fresh, and typically shows twinning, and parallel banding of white, grey or black, between crossed nicols. In unpolarised light, augite appears as colourless aggregates and small, well-formed crystals. Between crossed nicols, the augite, which occurs as broken patches, interstitial grains and long blades, is purplish-brown in colour. often with clear twinning. Magnetite forms the main opaque phase, with some ilmenite; both minerals are black and opaque. Although generally in very small quantities, quartz is widely distributed.
– The axe may have been made from a small cobble or pebble obtained locally from the Glacial Drift. It is more likely to have been made from a glacial erratic rather than a bespoke quarried block.
– The petrology is very similar to axe No C24, which is thought to be in Kendal Museum, but provenance details appear lost.
– Relatively speaking, stone tools manufactured from quartz dolerite rock in northern England are usually associated with large axe hammers. Overall, axes made from similar rock are far less common in the Archaeological Record.
– When coring, the rock is comparatively softer than similar unweathered rock obtained from outcrop, suggesting that the tool was made from rock obtained from a secondary source.
vi. Axe 70070/107
Macroscopically, in thin section, the rock is a light olive grey (5Y 6/1) with faint planar bedding/laminae, and randomly distributed >0.5mm diameter opaque patches in a homogeneous matrix.
Microscopically, this is an epidotised tuff with typical Group VI characteristics. The fine grained, intermediate matrix is composed of minerals with low interference colours, and consist mainly of angular to sub-angular clasts of rock fragments with some plagioclase microliths. Small patches of blue-green pleochroic amphibole are distributed randomly. Epidote rims are formed around some opaque mineral grains, and within larger aggregates; it also occurs as discrete crystals in the matrix or very thin veinlets. Some aggregates contain silica laths, especially those associated with pyrrhotite.
– This polished thin section was compared with 80 thin sections in the IPG Thin Section Slide Collection, all with reasonable secure find spots. A sub-set of thirteen thin sections provided a reasonable petrographic match, of which IPG Slide 432 is fairly typical. Around one half of the slides in the set-set provided a reasonable match with PTS 70070/107. From this comparative evidence, the most likely source area for the rock was within the geographical area bounded between Pike o’Stickle, Harrison Stickle and Thunacar Knot, with a preference westwards. Archaeological Site 123 is located centrally within this area.
– The closest match was provided with IPG slides Nos 556 and 557. These are labelled ‘Ehenside Tarn’. Therefore, by comparison, it is possible that Carlisle axe 70070/107 may have originated from a similar source. This is a very exciting and significant observation. But geochemical analysis, of both axe 70070/107 and the Ehen side Tarn axes, will be required to confirm, or otherwise, this observation.
– Although not as good a match as with the two Ehenside Tarn axes, the petrology and fabric of axe 70070/107 is similar to the coarser bands within Axe 2 of the Belmont Hoard of three Cumbrian Clubs (Davis and Edmonds SAS III forthcoming). But the match is not sufficiently good to indicate that it was manufactured from the same outcrop(s) as any of the three Belmont axes; but probably in the same area adjacent to Site 123. The petrological evidence suggests that the manufacture of the axe 70070/107, along with other Cumbrian Club tool types, may have taken place at different manufacturing sites within the same geographical area.
vii. Axe 70072/43
Macroscopically, in thin section, the rock is a pale olive (10Y 6/2).
Microscopically, the rock falls well within the range for Group VI. It is a fine grained epidotised tuff of andesitic composition. The matrix consists mainly of a turbid isotropic material, which contains epidote grains and microliths of feldspar. Random scatters of irregularly shaped grains of feldspar and cryptocrystalline silica, and more rarely sphene, may occur; they are most commonly associated with highly corroded feldspar fragments and pseudomorphs, possibly after pyroxene.
– There are sufficient similarities between this rock and IPG thin section No. 924 to suggest a possible source in the vicinity of Harrison Stickle.
– The axe morphology suggests a re-sharpened butt-end of a larger axe. In which case, the lithology of such a larger, pre re-worked axe is fairly typical of other ground and polished narrow-butt axes, of similar (projected) proportions, from Cumbria.
– Altered lithic fragments of volcanicalstic rock and rhyolite form a distinctive feature; a similar range of lithic inclusions also occur in IPG thin section C24 (an axe fragment in Kendal Museum (ref 791.23).
viii. Axe 70074/1
Macroscopically, in thin section, the rock is dark greenish yellow (10Y 6/6)
Microscopically, this is a medium grained, ungrouped volcanicalstic rock, which contains more silica and chlorite, and less epidote, than is normally found in rock from debitage and exposures adjacent to extraction sites around the Langdale Pikes. Rosettes of chlorite needles are characteristic of this rock, a feature relatively uncommon, although not absent, in thin sections from the Group VI rock variants from around the Langdale Pikes.
– Although the petrology does not match the published description for Group VI, it most certainly does match the petrology of the volcaniclastic rocks, especially in the western area of axe-making sites to the West of Stake Pass and around Scafell. It is very likely that, with further work, this rock can be matched to an outcrop or debitage within the geographical area of the axe production sites.
Above the Neolithic level there were Bronze Age features: a shallow deposit of burnt stone (a short lived Burnt Mound) and a small round ‘house’ with foundation ditch, wide doorway and a central hearth.
20. Ronaldsway Airport Extension, Isle of Man
This work on the very shore of the SE coast of the island revealed a Mesolithic round house similar to that found by Peter Woodman in 1984 a few miles up the coast at Cass ng Hawin. The house floor was in a hollow 6m across. Carbonised wood remains suggested that the floor might have had some sort of woven covering. There were no internal posts but the hollow was surrounded by 8 postholes, suggesting a tent-like structure similar to that at Mount Sandel and other contemporary sites. Associated with the house were 16,000 lithic flakes and tools, some hammer-stones and a ‘limpet scoop’. In contrast to Carlisle, microliths were relatively rare.