In order to characterize the microstructure of crystalline and polycrystalline thick materials, the Bragg diffraction pattern associated with the diffracted energy analysis allows texture determination, strain analysis, crystalline phase identification and grain size evaluation. This work describes an innovative application of a hard x-ray diffractometer, employed for the first time to obtain, in a non-destructive way, interesting microstructural information related to the production processes of archaeological finds. Two ancient bronze artefacts of different historical periods were selected to demonstrate an application of the method, which could be implemented at a museum. In fact drastically different structural characteristics were observed.

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In the framework of a research aiming to assess the suitability of neutron/x-ray non-destructive techniques for the characterization of archaeological objects, two bronze items were studied by neutron diffraction. The origins of two small statues are, respectively, Egyptian (XXI-XXX Dynasties, c1070-343 B.C.) and Etruscan (IV-III centuries B.C.), belonging to a private collection. By hard x-ray diffraction we previously verified that both statuettes have a coarse microstructure (big grains). From historical considerations we believe that both items were produced by solid lost wax processes of casting. This processing technique does not completely justify the presence of microstrains; as a consequence, due to unexpected neutron diffraction peak broadening, a non-uniform Sn wt% is suspected. In the present work we discuss this deduction by means of Rietveld analysis of the neutron diffraction profiles.