More observations on the problem of tempering in compositional studies of archaeological ceramics

Abstract Provenance studies of archaeological ceramics by means of chemical characterization may be complicated by the presence of temper in the ceramic paste. The impact of tempering on the compositional distinctiveness of ceramics derived from two distinct clay sources defines an “overlap curve” whose shape is described by the point of maximum temper effect and spread of temper effect. Values of these parameters are determined in part by (1) relative magnitudes of elemental concentrations in clays versus tempers and (2) the initial distinctiveness of the clay sources. Demonstration of these effects with artificially generated data is presented here.