ATR-FTIR spectral database for identification of archaeological materials

Fourier transform infrared (FTIR) spectroscopy is a versatile technique, particularly adapted to archaeological or cultural materials, that can be applied to organic and mineral materials. It is effective in analyzing poorly crystallized and amorphous materials, even at a microscale, when combined with microscopy. This is especially useful when measuring in Attenuated Total Reflectance mode (ATR-FTIR), which allows small samples to be quickly analyzed without preparation. However, the interpretation of FTIR spectra is complex and can be greatly facilitated by the use of a spectral database adapted to the material studied. In the case of archaeological or heritage materials, this requires access to spectral databases, including pure natural materials, as well as mixtures, materials transformed by anthropic processes (e.g. thermal transformation), and alteration products formed during burial and in museum collections. To this aim, a spectral reference database has been set up at the Muséum National d'Histoire Naturelle (Paris), mainly based on its own collections. This article presents this open access spectral database and highlights its applications.