Micro-PIXE Analysis of Pyrite in Lapis Lazuli for a Provenance Study

In this work we report about the micro-PIXE characterization of lapis lazuli rocks. These measurements have been carried out in the framework of a wider provenance study of lapis lazuli we are carrying on since 2008. An introduction to this study has already been explained in the last Annual Report of LNL. Due to the heterogeneity of lapis lazuli we concentrate our attention on single phases instead of the whole stone and this is one of the main motivations to use the micro-PIXE technique. In previous works we focused on lazurite, the main phase of lapis lazuli and on diopside, one of the most frequent accessory mineral of lazurite. In this work we focused on pyrite, another accessory mineral present in almost all the samples. Pyrite is an iron disulfide with chemical formula FeS2.