Real-Time Mid-Infrared Spectroscopic Analysis for Heritage Materials Characterisation

This proof-of-concept study presents the application of a novel, ultra-fast portable mid-infrared spectrometer for the non-destructive characterisation of heritage materials, including mineral-based materials, pigments, paints and polymers commonly found in artworks and historic objects. Selected spectral datasets were inspected using principal component analysis and hierarchical cluster analysis. The results enabled reliable monitoring of calcium sulfate hydration states, partial differentiation among blue and green pigment types, subtle separation of binder-based groupings between water-based and acrylic paints, and classification of synthetic foams into broad polymer families. Overall, this study shows that the technique can extract chemically relevant information in the 5000–2000 cm−1 region, with acquisition speeds that may enable applications not readily achievable using conventional portable mid-infrared systems, indicating potential for in situ monitoring and classification of heritage materials in museums, historic sites and conservation studios. Future developments will expand infrared coverage, integrate scanning and combine complementary techniques.