3.4 Ceramics

Three areas can be highlighted here – fabric and organic residue analyses and experimental work – all of which were reviewed at a meeting in Glasgow in 2010.

Fabric analysis

Petrographic analysis has been most suited to the study of coarse-textured pottery, in particular the identification of fabric groups. This approach has been applied notably to Neolithic pottery to define the main inclusions which often represent the tempering material. Where the site lies in a region of some geological diversity, results have been very encouraging; for example, the presence in Late Neolithic pottery at Barnhouse on Orkney of different igneous rocks occurring in the site’s vicinity has been exploited to reveal detailed information on the dynamics of intra-site potting practices at this settlement (see the ScARF Case Study: Grooved Ware at Barnhouse, Orkney

The accumulated experience is that pottery of later date is best examined by a combination of petrographic and chemical analysis. The focus of Roman Antonine Wall pottery studies has been on determining what classes were made locally; there is surely room to exploit this potential. Chemical analysis has been able to determine that medieval White Gritty ware was produced at many different locations in Scotland, the corresponding petrographic analysis providing supporting characterisation as well as more technological information. Medieval pottery from the Forth valley analysed by neutron activation analysis showed compositional grouping of ceramics from Throsk (Caldwell et al. 1992). The later Red wares of Scotland have proved to be very amenable to chemical characterisation. Furthermore, the chemical data for both these wares are being considered within a north European context.

As regards databases, some Scottish pottery has been entered into the UK ceramic thin-section database, now partly or wholly hosted by the AHDS, but this has not been updated comprehensively during the last fifteen years. Morris and Woodward (2003) address this issue as it affects prehistory pottery. There is no chemical database for Scottish pottery although in the 1980s SURRC (now SUERC) prepared with NMS an ‘E4’ ceramic standard (Topping and Mackenzie 1988).

Organic residue analysis (ORA)

This has been an active area of research in the last decade (see also section 4.4). In its earlier phase it concentrated on the lipid content in pottery on the basis of the relatively good survival of lipids over time and during burial; this approach was adopted in the study of residues in Grooved ware at Barnhouse on Orkney (ScARF Case Study: Grooved Ware at Barnhouse, Orkney and Table 3) and has worked to quite good effect elsewhere in Scotland. However, it has become increasingly recognised that more refined, more species-specific information is necessary. To that end, the group at Bristol led by Richard Evershed has pioneered the incorporation of the carbon isotope analysis of the C16 and C18 fatty acids into the analytical sequence. This has allowed the discrimination of sheep, pig and cow fats as residues in Grooved ware pottery. The welcome and complementary approach has been to look at the protein residue in prehistoric pots associated with dairying in the Western Isles (Craig et al. 2005; see also section 4.4). Almost all organic residue analyses to date have been on prehistoric pottery, although there has been analysis of samples of bog butter from the NMS collection (Berstan et al. 2004).

Concerning facilities, organic residue analysis has been undertaken on an ad-hoc basis in only a few laboratories/institutions in Scotland.

Table 3: Ceramics: a selection of recent fabric, technological and functional (organic residue) analyses

See also the ScARF Case Study: Grooved ware at Barnhouse, Orkney