Archaeological Chemistry in the OGU
In this research we are exploring new ways of deriving compositional information from organic remains of archaeological interest with a view to improving our understanding of human activity in the past. Gas chromatography (GC) and mass spectrometry (MS) are the primary techniques used in this work, particularly in combination, e.g. GC/MS. Gas chromatography combustion isotope ratio mass spectrometry (GC/C/IRMS) is a new technique we are using to derive information concerning the relative abundances of stable isotopes (C, N, O and H) in individual compounds which is assessed in combination with conventional structural and distributional information to determine the origins of organic residues from archaeological finds. The basis of our analytical approach is to match the properties (usually molecular structure) of individual compound(s) present in archaeological materials to those produced by modern plants and animals likely to have been exploited in antiquity.
Important areas of study include the processes of decay of organic residues during the prolonged burial of artefacts, and the effects of human intervention, such as that resulting from refining or mixing of natural products in antiquity. The principal areas of investigation include: (i) analysis of organic residues in the study of ancient pottery vessels and other artefacts; (ii) study of chemical marker compounds in soils at archaeological sites; (iii) use of GC/C/IRMS in the study of ancient diet and agriculture, and (iv) investigations of di- and triterpenoid components of ancient tars, pitches and resins. The archaeological materials studied come from excavations in the UK, Europe, the Near East and the Americas, comprising a wide range of archaeological time periods, e.g. Neolithic, Minoan, Roman, Bronze Age, Iron Age, Saxon, Medieval, etc.
The information accruing from our research in this new, interdisciplinary field is important in establishing a reliable basis for the interpretation of the nature and origins of otherwise intractable archaeological materials.