Provenance studies of archaeological marbles from the museum of Como by neutron activation analysis and data reduction.

The identification of provenance of white marble used in monuments or artifacts of historical and/or artistic interest, such as temples and sculptures, is quite important for archaeologists and art historians. The discovery of ancient pathways of trading networks, indirect dating of artifacts and the identification of forgeries are usually the aims of provenance studies. Correlations and similarities in the physico-chemical characteristics of marble samples from monuments and quarries may be advantageously investigated. Investigation based only on macroscopic characteristics, such as color and grain size may lead to wrong conclusions as it is well known that considerable differences in these properties have been observed in samples excavated from the same quarry. In recent years multielemental methods of trace analysis, such as neutron activation analysis and data reduction have been profitably used in provenance studies. A large number of variables (element abundance) can be thus obtained and consequently samples of different origin can be better separated. In the present paper white marble samples of Roman age monuments from the Archaeological Museum of Como (Northern Italy) were analyzed for their trace elements content. A number of elements, including rare-earth elements, were determined by neutron activation analysis. Results as well as precision and accuracy are presented and discussed. The application of discriminant and cluster analysis procedures and the use of some parameters based on rare-earth elements enables the marble quarries in the Mediterranean basin to be characterized on the basis of their trace element content and the provenance of the constituent marble of the monuments to be identified.