Historically, a very large variety of everyday artifacts were made of wood, which makes them representative of their historical period or social context and valuable for archaeologists and historians. In order to preserve degraded wood and to develop and apply suitable conservation treatments, chemical and physical characterization of archaeological wood is needed. This review provides the reader with a survey on state-of-the-art of instrumental analytical tools available to understand the morphology and the chemical composition of archaeological wood. The focus is on microscopic and spectroscopic techniques such as scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), Raman, nuclear magnetic resonance (NMR) and analytical techniques based on pyrolysis, such as direct exposure–mass spectrometry (DE-MS), pyrolysis–mass spectrometry (Py-MS), pyrolysis–gas chromtography–mass spectrometry (Py-GC/MS), with emphasis on their respective potentialities and limitations. The advantages of techniques based on synchrotron radiation are also discussed. In addition, the applicability of each examined technique is illustrated and discussed through specific examples from the literature.

Urushi is the oldest and most precious lacquer used since antiquity in East Asia. \ud For artistic purposes, in order to obtain suitable rheological properties, the lacquer is usually \ud mixed with a vegetable oil. In this work we investigated the curing process of urushi/tung oil \ud mixtures in order to highlight the chemical interactions at the molecular level between the two \ud materials. \ud A multi-analytical approach was adopted, based on thermogravimetry (TG), differential scanning \ud calorimetry (DSC), gas chromatography-mass spectrometry (GC-MS), evolved gas analysis\ud mass spectrometry (EGA-MS), analytical pyrolysis coupled with gas chromatography and mass \ud spectrometry (Py-GC-MS) and high performance liquid chromatography-mass spectrometry \ud (HPLC-MS). Fresh and aged mixtures were analysed and the results were compared with those \ud obtained from the analysis of the individual materials. \ud The data highlighted that different polymerization and oxidation mechanisms take place in \ud oil/urushi mixtures compared to the pure materials. Py-GC-MS and GC-MS showed that the \ud profile of aliphatic mono- and di-carboxylic acids was drastically different for the aged film of \ud pure tung oil compared to the mixtures. The ratio between the relative content of azelaic and \ud palmitic acids was much lower in the mixtures than in the pure oil, highlighting a lower level of \ud oxidation. On the other hand, the relative content of short chain carboxylic acids, which are \ud produced by pyrolysis of the cross-linked oil network, increased as the concentration of urushi in \ud the mixtures increased, thus indicating an increasing level of reticulation. HPLC-MS showed a \ud relatively higher amount of triglycerides with hydroxylated fatty acids – the intermediate \ud oxidation product of polyunsaturated fatty acids - in the mixtures with respect to pure tung oil