Eleanor Schofield: X-ray Absorption Spectroscopy in the service of Henry VIII: Conserving a Tudor shipwreck

The conservation of marine archaeological wood is complicated by the presence of iron and sulfur. The sulfur originates from sulfate ions in seawater being transformed by sulfur reducing bacteria, and iron from dissolved fixture and artefacts. Incorporated in to the wood as reduced sulfur/iron compounds, such as pyrite, they can become problematic during the drying of the wood as rapid oxidation can result in acid formation which can promote degradation. The Mary Rose was a 16th century Tudor warship, commissioned by Henry VIII. After 34 years sailing, the ship sank off the coast of Portsmouth in 1545. Rediscovered in the late 1960s, the remaining hull emerged from the Solent in 1982 and now resides in a purpose built museum in Portsmouth Historic. In 2013 the consolidation treatment of the wood, to compensate for degradation, was completed and an air drying process commenced. During this phase samples have been periodically taken to monitor the evolution of iron and sulfur as a function of drying time using X-ray Absorption Spectroscopy. Alongside this Fourier-Transform Infrared Spectroscopy has been used to correlate any observed changes to the degradation levels within the wood. This information is crucial in understanding the chemical state of the wood and designing future conservation strategies.

References:
1. Schofield, E. J., “Illuminating the past: X-ray analysis of our cultural heritage” Nat. Rev. Mater. 3, 285-287, 2018
2. Schofield, E. J., Sarangi, R., Mehta, A., Jones, A. M. and Chadwick, A. V. “Nanotechnology and Synchrotron light in the service of Henry VIII: preserving the Mary Rose” Materials Today, Vol 14 (7-8) Pages: 354-358 2011
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