Non invasive analysis of manuscript covers: portable X-ray fluorescence enlightening medieval jewellery masterpieces

This paper will present portable X-ray fluorescence (pXRF) analysis applied in situ to three 11th- 12th century manuscripts covers considered as masterpieces of Northern Italy medieval jewellery: Pace di Ariberto (Milano), Liber Evangeliorium of Vercelli and Pace di Chiavenna. These objects show a sumptuous decoration of golden leaves, plates and filigrees, enamels and casted gems. The aim of this research is to obtain information on manufacturing techniques and composition of the artefacts, considering possible analogies and differences that may be useful for art historians' discussion on manufacture place and artistic connections. XRF analysis was performed in order to determine the composition of the metals and enamels, and quantitative results, obtained using certified standards, undergo data treatment with multivariate analysis. The present paper will present a part of the results obtained on both the metals and glass materials, underlying the potential of pXRF in producing reliable results also when working in non-ideal conditions.