Lead isotopes in the context of the provenance of copper alloys and mutability processes in Lithuania from the second half of the 1st century to the 13th century AD

This paper presents the results of analysis of lead isotope ratios (208Pb/204Pb, 207Pb/204Pb, 206Pb/204Pb, 208Pb/206Pb, 207Pb/206Pb) in copper alloys combined with chemical composition studies of archaeological artefacts by inductively coupled plasma mass spectrometry (ICPMS). The study covers a total of 208 samples collected from 55 sites spread all over Lithuania. The chronological range of the study encompasses the period from the second half of the 1st century AD to the 13th century AD. The repeated recycling of copper alloys, the addition of scrap materials with varying compositions, and the mixing of lead from different geological ore deposits naturally alter the original chemical composition of the alloy. The continuous recycling and alteration of materials pose challenges in identifying the original connections between the regions of origin of copper alloy ores in southern Eurasia and the users of these raw materials in the eastern Baltic Sea region. Together with lead isotope ratio analysis, investigation of copper alloy types, copper groups, and metal working technological development fundamentally changes the idea of a linear exchange of non-ferrous metals. The analysis carried out in this research has enabled the identification of the provenance and dissemination of non-ferrous metal raw materials (alloys and scrap metal) as part of the European exchange network at local (the present territory of Lithuania), regional (the eastern Baltic region), and trans-European levels.