Identification and classification of iridescent glass artifacts with XRF and SEM/EDX

Art Nouveau (Tiffany, Loetz) and modern (Jack Ink, Strini Art Glass) irides cent glass fragments were characterized using energy dispersive X-ray fluor escence analysis (EDXRF) and energy dispersive X-ray microanalysis in a sca nning electron microscope (SEM/ EDX) in combination with factor analysis in order to obtain clustring, A characteristic of Tiffany glass fragments is leaded bulk glass, whereas i n the case of Loetz K-Ca-Si bulk glass could be determined. Modern glass fr agments show a high amount of Na (7 wt% in the bulk of Jack Ink) and 0.6-1. 5 wt% Sr in the bulk of Strini Art Glass. The contents of Si and Ca are sim ilar to Loetz glass. Furthermore, the differences in the structure of the g lass artifacts could be determined. The cross-sections of Tiffany show a la yered structure of the bulk without a specific surface layer whereas the cr oss-sections of Loetz glass reveal a homogeneous bulk material with one or two homogeneous surface layers in the BE-image. In the case of the Jack Ink a homogeneous bulk glass and an inhomogeneous multilayered surface could b e determined. Strini Art Glass show a homogeneous bulk glass and a homogene ous surface layer in the backscattered electron image.