Résumé
Reduced iron and sulfur species accumulated within waterlogged archaeological wood artefacts during their burial time. Oxygen exposure of the artefacts during recovery leads to acidification and salts precipitation, which
causes irreversible physical and chemical damages. Prior to accurately evaluating novel extraction methods, the procedures for creating analogous samples were evaluated for efficacy. Waterlogged wood analogues provide
access to a whole set of homogeneous and sacrificial samples that replicate characteristics of waterlogged archaeological wood in terms of content degradation and the presence of reduced iron and sulfur species. In this study, we evaluated the preparation of model samples from fresh balsa wood artificially contaminated with reduced iron and sulfur species. Wood degradation and the formation of reduced iron and sulfur species were assessed by Fourier Transformed Infrared (FTIR) and Raman spectroscopies and validated through statistic
methods, such as Principal Component Analysis (PCA). Among the three impregnation protocols investigated, one method appeared to be the most effective in term of iron sulfide formation, especially partially oxidized mackinawite Fe1-xS. The selected protocol proved reproducible and efficient on both fresh balsa and Neolithic
oak samples. From these observations confirmed by the PCA analyses on spectroscopic dataset, a suitable method to model waterlogged archaeological wood was established.