Diagnostic studies on Nuragic bronzes from Sardinia using a Monte Carlo protocol

In this investigation, a protocol combining the use of Monte Carlo simulations together with energydispersive X-ray fluorescence (EDXRF) analysis was used to determine the chemical composition of a set of objects from a private collection, apprehended by Carabinieri and without archaeological context. The artefacts are thought to belong to the Nuragic period from Sardinia, Italy (~1500 BCE to 500 CE). The protocol employed is a powerful and non-destructive method useful for cultural heritage applications where usually no sampling is allowed. The protocol digitally recreates the objects surface and generates random photons to interact with the volume. It was herein applied with the main objective of attesting the authenticity of the objects. The samples were simulated as multi-layered structures composed of bulk material and outer corrosion layer so the patina thickness and composition could be estimated as well by the X-ray Monte Carlo (XRMC) package. The method proved useful and powerful, capable of efficiently determining the composition and structure of most of the objects in a total non-destructive approach, attesting the existence of at least one fake in the set. Nevertheless, for a more throughout evaluation and a better estimation of the patina composition, the use of complementary non-destructive analytical techniques and further enhancements in the code package have shown to be required.