Concentrations of copper, zinc and lead as indicators of hearth usage at the Roman town of Calleva Atrebatum (Silchester, Hampshire, UK)

Although prima facie evidence for non-ferrous metal-working in the form of slag, crucibles, moulds, etc is present at the Roman town of Calleva Atrebatum at Silchester Hampshire, UK it has not yet been stratigraphically associated with in situ hearths; this can make the location of metal-working difficult to determine. This in turn raises the further question of the range of function of hearths in this urban context. The present study uses a combination of archaeological and analytical methods to attempt to determine the use of several hearth and hearth-related contexts within the on-going excavation at Insula IX. Using X-ray fluorescence (XRF) we were able to distinguish between probable industrial and domestic hearths based on elemental concentrations; for example locally elevated metal concentrations, in particular of copper, show evidence for the probable working of copper alloys at Silchester. Metals were found to accumulate in the silty layers associated with hearth platforms indicating that the tiles themselves do not appear to absorb metal spatter.