A Laser Ablation Study of Glass Samples from Three Eighteenth-Century Germanic-American Glassworks: Amelung, Stiegel, and Wistarburgh

Thirty-one sherds from three Germanic-American glasswork sites—Amelung in Maryland, Stiegel in Pennsylvania, and Wistarburgh in New Jersey—and eleven intact specimens of suspected eighteenth-century Germanic-American glass were analysed for major and minor components by electron microprobe and SEM/EDS and for trace elements using laser ablation (LAM-ICP-MS). The results show that the three factories produced similar and varied types of glass, including calcic and potassic variants, some of which contain lead. Despite similarities in their major elemental compositions, glass sherds from these three factories were found to have diagnostic minor and trace element signatures (e.g., P₂O₅, Zr, Nb, Th, Sc) that serve to distinguish them irrespective of glass type. Amelung glass is the most distinct in terms of these and other trace elements. It appears that the variation is attributable to the silica-sand source, rather than to other variables. Although two of the complete specimens were initially suspected to be have been made by Amelung, comparisons to the data presented herein indicate that all are consistent with a Wistarburgh origin. This study suggests that the analysis of trace element signatures may be an effective way to source eighteenth-century glass samples.