This is the first study on the differential distribution and concentrations of silver in ceramics recovered from archaeological excavations. The chemical compositions of 1174 pottery vessels from 38 Roman-period sites in Israel have been determined. Unusually high and variable abundances of silver were discovered in pottery samples of all vessel types and chemical compositions from four distinct archaeological contexts dating to late first century BCE to 70 CE Jerusalem. The large majority of the Jerusalem vessels could be distinguished by their silver abundances from all analysed pottery pieces recovered at rural sites outside Jerusalem, even when the pottery types and chemical compositions, except for silver, of pottery found within and outside Jerusalem were indistinguishable. The evidence is suggestive of a human origin for the high and variable silver abundances, and dispersion of the silver by aqueous transport. The differential silver concentrations found in excavated pottery from Jerusalem and other urban and rural sites suggest that attention to the distribution of silver in pottery from excavated contexts may be helpful for evaluating the nature and function of archaeological remains and patterns of urban contamination. a detailed description of HPXRF and INAA sample preparation procedures and measurement methods, see Adan-Bayewitz et al . 2004, 2-3).The chemical compositions of 1174 pottery vessels from Roman Judaea/Palestine, including 221 examples from several locations in late Second Temple period Jerusalem (Fig. 2), were determined by HPXRF. Twenty-four per cent of the Jerusalem samples had Ag abundances above 2.0 ppm. A total of 11 samples from locations outside Jerusalem ( N = 718 and 221 samples, from rural and urban sites, respectively) were found to have Ag concentrations above this level, and all of them were from cities.Although the new INAA coincidence method could detect Ag below 0.10 ppm and the HPXRF method could generally detect Ag at the level of 1 ppm, the Ag anomalies discussed in most of this paper will be those greater than 2.0 ppm as measured by the HPXRF method. This limit is sufficiently higher than the HPXRF counting error for Ag of ∼ 0.5 ppm as to make convincing the assignment of an anomaly measured only by HPXRF. The Ag abundances obtained with INAA coincidence measurements for splits of many of the same samples also measured by HPXRF, as well as the HPXRF data, are discussed below. MATERIALS