ASSIGNING THE ORIGIN OF CATALAN MEDIEVAL STAINED GLASSES BY PATTERN RECOGNITION METHODS OF X-RAY FLUORESCENCE DATA

Thirteen different components of six samples belonging to stained medieval glass windows and twelvesimilar samples found in the archives of Girona Cathedral(Catalonia,Spain)during restoration workwere determined by x-ray fluorescence analysis.The use of display and cluster analysis methods,principal components analysis,non-linear mapping,minimal spanning tree and agglomerativehierarchical clustering applied to these results,together with those of nine samples from the samecathedral previously studied,showed the presence of a quite compact cluster formed by the soda-typesamples,indicating a probably similar origin and confirming the peculiarities of this Mediterranean area.The potash-type glasses were highly scattered with little similarity among them,suggesting a likelydifferent source of these samples.The twelve glasses of strictly unknown origin were found to have a highdegree of resemblance to the samples of known context,thus excluding the possibility of them beingsamples made in a very different age or site.Three of them were classified into the same group as thewell-defined soda-type glasses by the pattern recognition method SIMCA.

ASSIGNING THE ORIGIN OF CATALAN MEDIEVAL STAINED GLASSES BY PATTERN RECOGNITION METHODS OF X-RAY FLUORESCENCE DATA

Thirteen different components of six samples belonging to stained medieval glass windows and twelve similar samples found in the archives of Girona Cathedral(Catalonia,Spain)during restoration work were determined by x-ray fluorescence analysis.The use of display and cluster analysis methods, principal components analysis,non-linear mapping,minimal spanning tree and agglomerative hierarchical clustering applied to these results,together with those of nine samples from the same cathedral previously studied,showed the presence of a quite compact cluster formed by the soda-type samples,indicating a probably similar origin and confirming the peculiarities of this Mediterranean area. The potash-type glasses were highly scattered with little similarity among them,suggesting a likely different source of these samples.The twelve glasses of strictly unknown origin were found to have a high degree of resemblance to the samples of known context,thus excluding the possibility of them being samples made in a very different age or site.Three of them were classified into the same group as the well-defined soda-type glasses by the pattern recognition method SIMCA.