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The Desana treasure is a remarkable assemblage of items made of gold, silver, gemstones and glasses found in north-western Italy. Most scholars agree on the fact that the core of the treasure might have belonged to a single deposit resulted from a long period of selection, accumulation and use. The treasure testifies to the evolution of goldsmiths' art in Ostrogothic Italy and represents an extraordinary material trace of the Italian elites of the 5th–6th centuries. The Desana treasure was investigated with non-invasive instrumental analytical techniques, namely optical microscopy, UV-visible diffuse reflectance spectrophotometry with optical fibres and X-ray fluorescence spectrometry in order to record the chemical features of gemstones, coloured glasses and precious metals employed to produce the items. As for the gemstones, besides identifying typologies, data suggested India as the source for a sapphire pendant and for most of the garnets, whereas the emeralds may belong to different sources, among which Pakistan, India and Egypt. The investigation revealed the colouring agents and compositional features of the glasses, and the composition of the gold alloys. The results of the investigation highlight that the raw materials used by Late Antique Italian goldsmiths did not differ significantly from other neighbouring European and Mediterranean regions, although the garnets show some differences if compared with coeval jewels recorded north of the Alps. The dataset produced in this work complements the stylistic approach for the study of these amazing traces of the past and deepens our knowledge on the role of the Italian "Ostrogothic" jewellery in the frame of the coeval Mediterranean, Central European and Northern Pontic metalwork traditions. [ABSTRACT FROM AUTHOR]

An illuminated Book of Hours (in use in Chalon-sur-Saône) currently owned by the Museo Civico di Arte Antica and displayed in the prestigious Palazzo Madama in Torino (Italy) was investigated by means of optical microscopy, fibre optic reflectance spectroscopy, fibre optic molecular fluorimetry, X-ray fluorescence spectrometry and Raman spectroscopy. The aim of the scientific survey was to expand the knowledge of the manuscript itself and on the materials and techniques employed by Antoine the Lonhy, the versatile itinerant artist who decorated the book in the 15th century. The focus was to reveal the original colourants and to investigate the pigments used in rough retouches which were visible in some of the miniatures. The investigation was carried out in situ by portable instruments according to a non-invasive analytical sequence previously developed. It was evident that the use of different pigments by the master was ruled, at least partially, by a hierarchical scheme in which more precious materials were linked to the most important characters or details in the painted scene. [ABSTRACT FROM AUTHOR]

The Coronation Gospels or Krönungsevangeliar is a manuscript kept in Vienna at the Kunsthistorisches Museum Wien, datable to the end of VIII century A.D. and produced at Charlemagne court. It is an example of a purple codex, i.e. its parchment is coloured in purple. It has to be considered as one of the most important medieval codices, according to its use to take oath in the coronation ceremony of kings and emperors of the Holy Roman Empire up to 1792. In order to gather information of the manufacture of the manuscript and its present conservation state, a diagnostic investigation campaign has been carried out in situ with totally non-invasive techniques. X-ray Fluorescence Spectrometry (XRF), UV-visible diffuse reflectance spectrophotometry with optical fibres (FORS), spectrofluorimetry, optical microscopy and multispectral analysis have been applied in order to identify the colourants used in the decoration of the manuscript, with the main concern to the dye used to impart the purple hue to the parchment. The information collected was useful in order to address some of the questions raised by art historians concerning its history. [ABSTRACT FROM AUTHOR]

• FORS can be used to authenticate Limoges enamels. • Typical absorptions of transition metal ions can be highlighted. • PCA is applied to discriminate mediaeval and modern enamels. • The role of Fe and Mn ions in the reflectance spectrum is discussed. In this work we used UV–visible–NIR diffuse reflectance spectrophotometry with optic fibres (FORS) in order to point out differences between mediaeval and 19th–20th century champlevé enamels previously analysed with X-ray fluorescence spectrometry (XRF). FORS spectra of enamels collected in diffuse reflectance mode made it possible to obtain information useful not only for identifying the colourants of the enamels, but also for evaluating the authenticity of the artworks. By means of pattern recognition techniques, it was possible to highlight relevant spectral features useful for the discrimination of objects, the authentication of which was previously verified by means of elemental analysis (XRF). The role of transition metal ions, mainly iron and manganese, in the reflectance spectrum, has been critically discussed. FORS proved to be a highly reproducible technique, capable of detecting the chromophores in a glass matrix in a non-invasive and rapid manner. A comparison with historically accurate reference glass and enamels, together with data from other analytical techniques, was essential for validating the method. Furthermore, once the FORS methodology was defined, the results obtained showed great accuracy and reliability. [ABSTRACT FROM AUTHOR]