Red organic colorant used to dye textile artifacts: From mock-up samples preparation to analytical characterization

The study here presented concerns the characterization with chromatographic (highperformance liquid chromatography, HPLC) and spectroscopic (Raman spectroscopy and UV-Vis spectroscopy) techniques, of red dyestuffs used to dye the yarns of ancient tapestries. Following the ancient recipes, the yarns (wool and silk) have been dyed using natural red dyes such as madder, kermes and cochineal. This allowed the preparation of mock-up samples used to realize a reference database. By SEM-EDX (scanning electron microscopy coupled with energy dispersive X-ray analysis) the yarns morphology has been investigated and the presence of the metals responsible for the specific mordants employed has been confirmed. Attention has been also paid to develop a non-destructive approach to be applied in-situ.