The preliminary results on the investigation of historic stained glass panels from Grodziec collection, Poland

Abstract

Grodziec collection of stained glass panels consists of fourteen objects depicting figures of saints. Probably they belong to one, uniform set from the one of Lower Silesia churches. Recently eight of them, already after conservatory treatment, are exhibited in Jagiellonian University Museum of Collegium Maius in Krakow, while remaining six, which will be restored in nearest future, are stored in the National Museum in Wroclaw. This paper presents the results of the investigation of composition and corrosion products of glass from three panels of Wroclaw group. Since comparative analysis of historic glass composition is vital for its dating, to obtain the possibly full set of composition data with particular stress on light elements identification, the multi technique approach was necessary. The physicochemical analysis was carried out by X-ray fluorescence (XRF), micro-Raman spectroscopy and scanning electron microscopy with energy dispersive X-ray spectrometer (SEM/EDX). The study revealed that some of stained glasses have composition characteristic of northern medieval glass (potash-lime-silicate) while other pieces could be dated on 16th or 19th century. This confirms the suggestion from the former historic and scientific investigation of Krakow's set that the Wroclaw panels may be of the same medieval origin as the Krakow's ones and that they were already restored, at least in 19th c. The possibility of working on the whole set of panels from the Grodziec collection opens up the opportunity for conducting exceptional scientific study which will lead to the definitive designation of the provenance of this important collection, its history and age.