Comparison of trace element chemistry in human bones interred in two private chapels attached to Franciscan friaries in Italy and Denmark: an investigation of social stratification in two medieval and post-medieval societies

Individuals buried in two 17th–18th Century private chapels, each attached to a Franciscan Friary—one in Italy the other in Denmark—have been studied and sampled for trace element analysis. This selection of individuals allows a comparison of the trace element inventory of members of noble families against friars and townspeople, as well as a comparison between two very similar situations in Denmark and Italy. The relevance of this study is to see if and how differences in social status, and therefore likely differences in dietary habits, are reflected in the trace element chemistry of the bones. Samples of cortical and trabecular tissues have been procured from a long bone, preferentially the femur. The samples have been thoroughly decontaminated. 87 samples from 69 individuals have been analysed for Ca, Mn, Fe, Cu, Sr, Ba, and Pb by ICP-MS and Hg by CV-AAS. Sex and age at death have been established by anthropological analysis for all members of the two noble families. We find systematic differences between the noble family members and the friars (or townspeople) in both Italy and Denmark. The noble families are in both cases low in Sr and Ba compared to the friars and townspeople, which is interpreted as a dietary signal resulting from higher meat consumption than in the comparative groups. Lead concentrations are found to be higher in the noble family members than in the comparative groups, and the Pb concentration seems to increase with age in the Italian noble family, where both young and middle-aged individuals were investigated. Mercury concentrations are higher in some of the Italian noble family members compared to friars and townspeople; whereas in Denmark it seems that Hg was equally available to the noble family members and the friars alike. This is the first comprehensive and comparative study of post-medieval noble families in Denmark and Italy. The results show that there are distinct similarities in the trace element distribution patterns in the noble family members irrespective of country, which is tentatively suggested to be due to their higher social status.