Identification of archaeological triterpenic resins by the non-separative techniques FTIR and 13C-NMR: the case of Pistacia resin (mastic) in comparison with frankincense

The use of spectroscopic techniques such as Fourier-​transform IR (FTIR) spectroscopy and carbon 13 NMR (13C NMR) using the J-​mod expt. is proposed as an effective alternative to gas chromatog.-​mass spectrometry (GC-​MS) for the anal. and identification of natural resin samples found in archaeol. environments. The spectral features of the most common diterpenic and triterpenic resins and also two gum-​resins are reported and discussed for both techniques. The anal. procedure based on the combined use of FTIR and 13C NMR is then applied to two archaeol. samples from the Milano of the Roman age allowing their identification as Pistacia resin, or mastic, as confirmed by the traditional GC-​MS method, and also elucidating some effects of aging on such material.