Lapis Lazuli is one of the oldest precious stone, being used for glyptic asearly as 7000 years ago: jewels, amulets, seals and inlays are examples ofobjects produced using this material. Only few sources of Lapis Lazuli exist inthe world due to the low probability of geological conditions in which it canform, so that the possibility to associate the raw material to man-made objectshelps to reconstruct trade routes. Since art objects produced using LapisLazuli are valuable, only non-destructive investigations can be carried out toidentify the provenance of the raw materials. Ionoluminescence (IL) is a goodcandidate for this task. Similarly to cathodoluminescence (CL), IL consists inthe collection of luminescence spectra induced by MeV ion (usually protons)irradiation. The main advantage of IL consists in the possibility of working inair while measuring simultaneously the composition of major and trace elementby means of complementary Ion Beam Analysis techniques like PIXE or PIGE(Particle Induce X-ray or Gamma-ray Emission). In the present work a systematicstudy of the luminescence properties of Lapis Lazuli under charged particlesirradiation is reported. In a first phase a multi-technique approach wasadopted (CL, SEM with microanalysis, micro-Raman) to characterise luminescentminerals. This characterisation was propaedeutic for IL/PIXE/PIGE measurementscarried out on significant areas selected on the basis of results obtainedpreviously. Criteria to identify provenance of Lapis Lazuli from four of themain sources (Afghanistan, Pamir Mountains in Tajikistan, Chile and Siberia)were proposed.
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