PROFESSOR DEREK HAMILTON, SUERC, University of Glasgow takes us on a journey into the fascinating world of the application of isotope studies in archaeology. In the past 10 years sulfur isotope analysis has become increasingly used to investigate the movements of prehistoric people and animals. Sulfur isotopes preserved in bone and teeth collagen give us insights into the geology and coastal proximity of where an individual lived, as well as diet, and refined sampling  techniques are extending our ability to reconstruct mobility throughout an individual’s lifetime, rather than ‘one off’ movement.

This paper presents the differential approach to sampling for sulfur isotope analysis applied to human and animal populations from Middle Iron Age (~400–200 cal BC) sites in Wessex and East Yorkshire, England. It presents insights gained not only on the archaeological questions about movement and mobility in these past populations, but perhaps more importantly on how the data are interpreted. We have learnt that underlying geology strongly influences the final sulfur isotope value from a sample, and so statistical tools can be used to begin to robustly model the expected prehistoric values for specific geologies that can then be applied to other unknown datasets.