In 2014, the Museum collaborated on a study conducted by Dr Cristina Scibé on the metallic threads present in the decoration and weaving of medieval fabrics of Arab manufacture or influence. The study particularly focused on Hispano-Islamic fabrics from Al-Andalus and textiles from Sicily and Lucca, dating from the eleventh to the fifteenth centuries. The scientific-analytical research obtained from the analyses of micro-samples was carried out thanks to the collaboration of two important institutes dedicated to the conservation and restoration of cultural heritage: Instituto de Patrimonio Cultural de España in Madrid and Opificio delle Pietre Dure in Florence.

The main objective of the study was to learn about the processing technology (materials and techniques) of metallic threads through the analysis of specific case studies selected from the most interesting international textile collections in order to identify the artisan technique used and understand how this spread and developed in the different Arab textile factories (Tiraz) within the territories dominated by Islam.

In connection with the studies for the experimental reproduction of a cloth from the Francesco di Marco Datini Firm in Prato, the Museo del Tessuto, with the consent of the State Archives of Prato, requested a specific investigation into the dye substances present in some wool samples attached to the merchant’s business letters. In 2013, the letters were deposited at the Opificio delle Pietre Dure in Florence, which enabled the micro-sampling of fibres from the samples using conservative techniques.

The analyses conducted by the OPD under the direction of Susanna Conti and in collaboration with the University of Pisa (Faculty of Chemistry and Industrial Chemistry) also included non-invasive examinations (such as radiography). The morphological analysis of the samples, useful to identify the nature of fibres and yarns, was conducted by observing the samples under a stereomicroscope. Subsequently, after the samples were prepared, the analysis continued by observing them under an optical microscope in transmitted visible light using various magnification lenses. High-performance liquid chromatography (HPLC) with a UV-Visible diode array detector (DAD) and with confirmation by HPLC combined with high-resolution tandem mass spectrometry (HPLC-ESI-Q-ToF) was employed to identify the dyeing material. The dye was hypothesised on the basis of the presence of the specific molecular markers contained within and, in some cases, also assisted by the semi-quantitative analysis of the same.