Scientific investigation and study of the sixteenth-century glass jewellery collection of Archduke Ferdinand II

Abstract

The glass jewellery collection of Archduke Ferdinand II, today part of the Collection of Sculpture and Decorative Arts, Kunsthistorisches Museum, Vienna, Austria, is a rare example of early modern lampwork. The small glass items, made by shaping fine glass rods and tubes in front of the flame of an oil lamp, date from before 1596. Although lampworked glass objects must have been popular collectibles, only a few pieces have survived. Therefore, the examination of this collection is a unique opportunity for the study of sixteenth-century lampworking technology. The rarity of the glass objects limited the examination to non-destructive methods. Optical microscopy provided an overview of the glass colours and surfaces. Subsequently, non-invasive portable energy dispersive X-ray fluorescence analysis (XRF) was carried out to classify the glass types. Further invasive investigations were carried out with micro-invasive electron probe microanalysis (EPMA) and energy dispersive X-ray microanalysis in a scanning electron microscope (SEM-EDX) on samples obtained from fragments of the jewellery, to identify the composition of the glasses specifically produced for lampworking, and the glassmaking tradition to which they belong.