Vikingatida förgyllningstekniker : En studie av förgyllningstekniker tillämpade på föremål från Birka med SEM-EDS

Sammanfattning: Studies with primary focus on Viking age gilding techniques in Scandinavia has not been carried out since the sixties. During the past 50 years knowledge about prehistoric gilding techniques and traces of them in the archeological material, as well as the usage of natural sciences within archaeology, has developed considerably. The aim of this thesis was to revisit the topic of gilding and shed new light on Viking age metalworking in Scandinavia with focus on gilding techniques. The second aim was to determine the possibilities and limitations of the study of gilding with a non-destructive methodology. The surfaces of 13 metal objects, four of which are indigenous and the rest are imported goods, were analyzed with SEM-EDS. The chemical compositions of the gilded layers as well as the underlying silver- or copper alloys were analyzed. Furthermore, observations of micro morphological structures were carried out on the gilt surfaces. Interpretations of both chemical compositions and micro morphology were carried out in order to identify what technique or techniques have been used for gilding. The results show that two of artefacts have not been gilded at all, five of them have been fire gilded and the results of the remaining six objects are inconclusive mainly due to lacking reference data. It can be concluded that further research regarding the aging of gilt surfaces on gilded artefacts, more specifically the loss of mercury in fire gilded surfaces over time, needs to be carried out.