The sunk-panel book-binding of a Renaissance Venetian Commissione Dogale: the scientific examination of the decoration materials

The research aims to investigate the nature of the materials used in the decoration of the cover of a sunk-panel Commissione Dogale, a Venetian manuscript of 1582. The analysed volume Ms. It. VII, 1869 (= 8134) belongs to the collections of the Biblioteca Nazionale Marciana, Venice. The Commissioni were intended as official documents written on parchment and issued by the Doge of Venice. Their bindings were very rich in decoration, especially those produced in the late 16th century. This manuscript is a sumptuous example of the Venetian Renaissance artisanship influenced by Middle Eastern style: its cover was made of gilded leather, painted with arabesque branches and buds and lastly lacquered. The scientific examination of the lavishly illuminated cover was performed before the book-binding conservation treatment, as the characterisation of the decoration materials allowed to plan an appropriate conservation project. The research first step has been the non-invasive observation of the cover surface by digital microscope through UV–VIS radiations. Then, the study of the composition of these materials has been carried out with ATR-FTIR spectroscopy, Raman spectroscopy, XRF spectroscopy and spot-test analyses on samples. Pigments like minium, green earth, a lead-based yellow and smalt have been detected in the painted layer, while a precise identification of the resins and varnishes layered on top of the decoration was not possible because of the heterogeneity of samples. Furthermore, the materials used for this cover can be usefully compared with those detected by other recent analyses carried out on a variety of 16th century Venetian book illuminations.