Case Study: Imaging techniques

Case Study 7

Imaging techniques: the ‘Making a Mark’ project.

Andrew Meirion Jones and Marta Díaz Guardamino

 


Figure 1: The Monkton Up Wimborne, Dorset chalk block exhibiting carved surface. Courtesy Martin Green RTI Image. © Andrew Meirion Jones/Marta Díaz Guardamino

The ‘Making a Mark’ project aims to build a greater understanding of the mark-making practices associated with a suite of Neolithic decorated artefacts from across Britain and Ireland. It does so by utilising a suite of digital technologies, including RTI, photogrammetry (using Agisoft Photoscan) and digital microscopy (using a Firefly GT200 at up to x230 magnification). Theoretically its aim is not to produce more accurate images of artefacts, but to use digital technologies as a means of imaging processes of working and reworking associated with these artefacts: to understand sequences of marking. Comparisons are then made between communities of practice within three main regions:

    • 1. Southern England (from Cornwall in the west to East Anglia, and as far north as the Thames Valley) to examine the working of chalk artefacts (see Figure 1)
    • 2. The Irish Sea region (including Wales, Isle of Man and eastern Ireland) to examine artefacts from passage tomb contexts and settlements (see Figure 2)
    • 3. Northern Isles and Northeastern Scotland (including Orkney, Aberdeenshire, Kincardineshire, Perthshire and Fife) to examine carved stone balls and the rich artefacts from Orcadian settlements.

The carved stone balls of Scotland form the ‘centrepiece’ of the project as the aim of the project is to provide a context for understanding these poorly contextualised, but intriguing, Neolithic artefacts.


Figure 2: Slate plaque ‘d’ from Ronaldsway, Isle of Man recorded using RTI. A1 shows detail of design at centre of obverse of plaque. B1 and B2 show evidence for polishing/erasure marks at tip of plaque on reverse side, while B2 shows designs beneath these erasure marks. B3 shows detail of marks at centre of the reverse of the plaque.  Image courtesy The Manx Museum. RTI Image. © Andrew Meirion Jones/Marta Díaz Guardamino

Results from the project (mainly using RTI) have been excellent. We have identified evidence for erased motifs on the remarkable decorated chalk cylinders known as the Folkton Drums, Yorkshire (Jones et al. 2015), evidence of reworking on antler maceheads, such as the decorated example from Garboldisham, Norfolk (see Figure 2) and reworking on the decorated portable stones from the great passage tomb Knowth. Probably the most remarkable results of the project so far have been from the decorated slate plaques from the Isle of Man where detailed RTI analysis shows clear evidence for the repeated decoration and revision of marks on these delicate slate artefacts; the plaques are in fact palimpsests of activity.

At the time of writing the project is just beginning to examine the Scottish carved stone balls. The results of RTI data capture on carved stone balls from Marischal College Museum, Aberdeen are presently being processed (April 2016), but preliminary results look extremely promising and we suspect similar practices of revision and reworking probably occur in Scotland.


Figure 3: One of the spiral designs from the Garboldisham antler macehead recorded using RTI. The image exhibits a clear stratigraphic relationship between the carved spiral and polishing striations on the surface of the artefact suggesting two phases of carving events. Courtesy Moyse’s Hall Museum/West Stow Anglo-Saxon Village. RTI Image. © Andrew Meirion Jones/Marta Díaz Guardamino. 

Methodologically the project has dealt with the data capture of marks on the surfaces of a variety of different materials, including chalk, bone, antler and a variety of stone. Chalk proved extremely difficult (but not impossible) to record due to its reflectant properties, while the dark non-reflective surfaces of slates have proved extremely amenable. Finally, it is hoped that the project will provide a benchmark for the analysis of this suite of different materials, and for combining new digital technologies with fresh theoretical perspectives.