A new protocol for the chemical characterisation of steatite – two case studies in Europe: the Shetland Islands and Crete

Steatite has been one of the most difficult materials of archaeological interest to characterise by physico-chemical methods of analysis with a view to identifying its origin. This paper presents a new protocol for the chemical characterisation of steatite based on the analysis by ICP-MS in tandem with INAA of rare earth elements (REE) and some transition metals in geological steatite from several outcrops on the Shetland Islands and on Crete. The major advance over earlier work has been the secure determination of REE at low concentrations. The results have demonstrated the ability to discriminate chemically three of the known Viking Age sources on Shetland. On Crete, although the situation is complex, four sources in the centre of the island have been partially differentiated. This study has also shown that first mineralogical analysis (by XRD) of steatite provides valuable supplementary characterisation data, and second strontium isotope analysis has promising potential for the sourcing of steatite.