XRF Spectroscopy and Shipwrecks: scanning biochemical fingerprints

The Swedish warship Vasa sank in 1628 and has been the subject of conservation and preservation treatments since its salvage in 1961. Henry VIII’s flagship the Mary Rose sank in the Solent in 1545, was discovered in 1971 and raised in 1982. She is now in the final stages of conservation.

Waterlogged wood often presents  as well preserved; the irony is that the actions of conservation can initiate or accelerate chemical processes which put at risk both delicate archaeological traces and the long term stability of the construction. Understanding these processes and how they are related to the context of the wreck site enables the prediction of preservation status in terms of the accumulation of inorganic contaminants in the wood caused by microbial invasion of the timbers.

This article in Spectroscopy Europe describes the use of X-Ray Fluorescence spectroscopy in the biochemical fingerprinting of recovered timbers, namely, the accumulation of iron and sulphur in wood cores. The technique need not be confined to ships; submerged timbers are a feature of other cultural heritage sites, both historic and prehistoric. XRF methodology may have applications in the analysis of microbial metabolites in these substrates.