Biblioteca Queriniana - Brescia

The analytical investigation carried out at the Biblioteca Queriniana in Brescia was focused on the characterization of the Codex Brixianus, a 6th century Latin Gospel Book which was probably produced in Italy. The study was carried out via FORS, portable X-ray fluorescence spectrometry (p-XRF), as well as multiband and hyperspectral imaging techniques, In order to identify the materials used, understand manufacturing techniques and assess its current state of conservation.

FORS, hyperspectral imaging and UVL set up.

The purple dying of the parchment clearly differs from what was observed in the other codices investigated in the framework of the Purple Project. While FORS allowed identifying a mixture of orchil and indigo/guado in the first section (the Canons), the investigation of the second section (the Gospels) stressed a more peculiar use of different dyes, i.e. folium and orchil. Hyperspectral imaging was particularly useful as it allowed mapping the distribution of the different dyes, even within the same page. This peculiar distribution of different dyes in the same page is rather uncommon in the context of purple codices and further investigations could be useful to verify if the same technique was used in its twin codex, the Codex Argenteus at the Uppsala Universitetsbiblioteket.

Significant differences in the chemical composition of the inks used in the two sections of the Codex Brixianus were also observed. Concerning silver inks, higher amounts of silver, gold, copper and lead were detected in the Gospels section, while Fe-rich silver inks were detected in the Canons section. On the other hand, gold inks showed a more homogeneous composition; the higher amounts of sulfur detected in the gold ink of the Gospel section was correlated to the use of different additives during grinding procedures.