Rooted in the long tradition of Raman spectroscopy of cultural heritage materials, in this work we provide a personal perspective on recent applications and new frontiers in sampling modalities, data processing, and instrumentation.

International audienceVarious natural organic film-making media from several chemical families have been used as varnishes. An improvement in the identification of these materials by the combination of Raman and infrared spectroscopies is here presented. Fourteen unaged reference samples representative of resins, glues, gums and oils were analyzed. FT-Raman and IR spectra were all compared in order to discriminate the different classes of organic media by considering their spectroscopic features. It led to a flowchart for material discrimination based on simple, notable and specific criteria. It appears that the different families (gums, glues, oils and resins) and subfamilies (di/triterpenoids resins) are easily differentiated thanks to their specific structural composition. However, discerning between compounds from a same subgroup, for example diterpenoid resins, could be ambiguous because the spectra depend on the sample aspect, age and degradations