Chemical composition overview on two organic residues from the inner part of an archaeological bronze vessel from Cumae (Italy) by GC-MS and FTICR MS analyses

A bronze vessel, containing solid black material, was found in a grave dated to the late eighth century BC and located in the Middle Tyrrhenian region. Two residue samples of this black material were subject to molecular characterization in order to assess first its composition and then the function of this precious object. Two different technique analyses, namely gas chromatography-mass spectrometry (GC-MS) and electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry, in negative-ion mode (ESI(-) FTICR MS), were employed in that way. If GC-MS analysis is commonly used for the characterization of archaeological samples by identifying biomarkers related to organic material, FTICR MS was used to achieve a fast global molecular description with up to thousands of assignments. In addition, this technique enabled to hypothesize about the different materials involved in the black material composition. As a result, lipids, beeswax, conifer resin, and pitch from birch bark were supposed, which was thereafter confirmed by GC-MS. Consequently, FTICR MS can be regarded as an efficient tool for the fast profiling of the organic archaeological compounds.