In this work a new approach to the physicochemical characterization of polychrome archaeological glasses through
elemental maps is presented. It is the first time that elemental mapping both by Laser Ablation-ICP-MS and EPMAWDS
was performed on ancient glass.
The glass elemental mappings are here proposed as useful tools for a preliminary study of the overall pattern of a
glass surface concerning each analyzed element. The visual inspection of the maps gives the distribution of the elements
and their degree of homogeneity; this allows the identification of the correlations between elements, in order to get
information about chromophores, opacifiers and their associated ores, as well as about the glass deterioration.
The LA-ICP-MS quantitative elemental maps of 54 elements were performed on a glass sample area. The
concentrations of the element oxides were visualized in pseudo-colors, both in 2D and 3D. EPMA-WDS elemental maps
were performed on areas of surface and break-section of the samples, at the interface between bulk and decorations. LAICP-
MS elemental mapping can be functional to the determination of the glass chemical composition patterns and of
associations between elements, while WDS elemental mapping is mainly aimed to identify the distribution of crystalline
phases or to visualize concentration gradients of elements at the interfaces of different areas, such as bulk and
decorations. Both the techniques can be functional to the study of glass superficial weathering.
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