In Hunter, Cowie and Heald’s review of research priorities for Archaeometallurgy in Scotland (2006) they pointed out the potential for more systematic research in Scotland, particularly making the case that there has been comparative little work on metal sources, or indeed on the comprehensive examination of the wealth of artefactual evidence in museum collections. The existence of ore sources across Scotland is widely known, and there is plenty of evidence of metal working, but few have been the subject scientific excavation. It is only comparatively recently that, for example, there has been an extensive synthesis of mould and crucible fragments (Heald 2005). Likewise only a small fraction of the extensive holdings of the NMS have and been investigated analytically or technologically, with a similar situation in other major collections.
At the same time the ability of new scientific methods to obtain good precision compositional data without sampling or with micro samples has increased dramatically. While the need to ensure that any analysis is truly representational remains a key issue (ie it is not skewed by surface corrosion, inhomogeneity, applied layers etc) the feasibility of gathering large analytical data sets is now more limited by research personnel than by technique, although equipment and facilities regularly available for archaeological and historical artefact analysis remains a limiting factor.
A selection of recent work is summarised in Table 4, a list that indicates the opportunities for further work are substantial. The authors adopt and extend the recommendations of Hunter et al.:
- Identification and study of mines and metal sources (with a focus on proxy environmental records as a first step).
- Definition and interpretation of regional alloy patterns at all periods.
- Broad study of ironworking evidence in Scotland to produce models of its organisation, similar to the recent synthesis of non-ferrous metalworking.
- Metallographic study of artefacts to understand iron technology and its influences in Scotland, notably the question of any Roman influence and changes in the Early Historic/Norse period.
- Continuation of analytical study of precious metal artefacts from the archaeological through to historical periods to accumulate more data for investigating trade and exploitation.
- Technological and analytical examination of key artefacts particularly using newly available methods such as micro CT imaging.
- Developing links between lead ores and lead incorporated into base and precious metal alloy artefacts using lead isotopes.
Table 4: Metals: a selection of recent investigations
| Analysis | Technique | Publication | Comment | |
|---|---|---|---|---|
| Prehistoric gold | Micro-chemical | Chapman et al 2006 | Gold sources; Irish case study (Chapman et al. 2006) could be usefully applied to Scotland | |
| Bronze Age Cu alloys | Isotopic | TIMS | Rohl and Needham 1998 | |
| LBA Cu alloys | Chemical | ? | Cowie et al. 1998 | Circulation zones; alloying traditions |
| IA/Roman iron | Metallography | McDonnell 1998a, b | Iron working on broch sites | |
| Roman Cu alloys | Chemical | XRF | Dungworth 1997 | Alloying traditions |
| Viking and later silver | Chemical | XRF | Kruse and Tate 1995 Eremin & Tate in Glenn,Wilthew (1995) |
Silver sources and recycling zones Technology and typology |
| Norse Cu alloys | Chemical | XRF | Eremin et al. 2002 | Alloying traditions |
| Medieval and later iron and iron slag | Metallography and SEM-EDAX | Photos-Jones & Atkinson 1998; Photos-Jones et al 1998 | Iron technology; operation of iron bloomeries | |
| Traditional ferrous metals | Chemical and mechanical | SEM-EDAX, HHXRF, mechanical stress tests | Wilson (forthcoming) | Conservation and maintenance of traditional ironwork (HS in partnership with Napier University) |
| Excavated iron | X-radiography | Excavated iron from multiple periods and sites, routinely X-rayed at NMS | ||
| Pewter | Chemical | XRF | Wilthew et al. 1988 | Survey of Scottish pewter compositions |