Origins of medieval lead glass ornaments in Central Europe in the light of lead isotopic analysis of finds from Wrocław and Sypniewo (Poland)

Lead glass ornaments are common throughout Central and Eastern Europe from 10th to 13th c. They are regarded as a local product due to the discovery of glass crucibles, semi-finished products and an ore deposit. Technological (electron probe microanalysis) and provenance analyses (lead isotope analyses) of eleven fragments of high-lead-glass jewellery from Wrocław (SW Poland) and high-lead-glass and lead-potassium glass (Slavic lead-ash glass) from Sypniewo (NE Poland) confirmed the use of local lead deposits. The isotopic composition of glass from this area has not yet been determined, except for one site in SW Poland. The chemical analysis shows early medieval glass production originated from the Silesian Upland and Lesser Poland. • Provenance study of lead glass from Poland. • We combine elemental and lead isotope analyses. • We identify a local glass-making tradition. • Lead glass popularity coincides with intense lead exploitation in the region.