Archaeological ceramic differentiation using trace element patterns

Ceramic sherds of "primitive" manufacture from an archaeological site on Fuga Moro Island, Philippines, were analyzed for trace element contents using energy dispersive X-ray fluorescence (EDXRF) to ascertain the probability of obtaining differentiation between stylistic classes (wares) and technological types within the ware. Following analysis and differentiation of these samples, using standard archaeologic and petrographic techniques, the initial focus of the study was to isolate surface factors which could distort or otherwise affect the final elemental characterizations. Once these factors were identified and eliminated, a simple procedure was then developed employing trivariate analysis of specific observed elements that unambiguously segregated the studied sherds, both according to ware and technological type within each ware. The key elements for ware differentiation were Zn, Br, and Sr while type differentiation was achieved using Ca, Ti, Mn, and Rb.