Mass-resolved ion scattering spectrometry for characterization of samples with historical value

The layer-by-layer atomic composition of major elements (Cu, Ag, and Au) in the medieval Venetian coin has been measured by mass-resolved ion scattering spectrometry (MARISS) using 1 keV Neþ–Heþ mixed ion beam for both controlled erosion of the sample (up to 0.3 mm in a depth) and simultaneous generation of analytical signals. Quantification was carried out by calibration using pure standard materials. It was shown that the surface of the coin is significantly enriched in silver (ca. 80 at.%), whose content tends to decrease inward the coin. Formation of the Ag-enriched layer (or surface depletion in copper) could be caused by the environment the coin was exposed to for many centuries. # 2003 Elsevier B.V. All rights reserved.