The Mary Rose - Henry VIII’s favourite warship whose remains were brought to the surface in a massive salvage operation broadcast to over 60 million people around the world 39 years ago this month - has received a major boost to help conserve the ship for future generations.

A team of researchers, led by Professor Serena Cussen from the University of Sheffield, has used a new x-ray technique available at the European Synchrotron Radiation Facility (ESRF) to discover the presence, location and structure of nanostructured bacterial byproducts lodged within the ship’s wood that could contribute to Mary Rose wood degradation.

The remains of the ship are currently on display in a purpose-built museum at Portsmouth Historic Dockyard, but they are vulnerable to degradation after spending more than 400 years at the bottom of the sea where harmful deposits collected inside the ship’s wooden hull.  These deposits originate from degradation of metal fixtures and artefacts after centuries spent under the seabed and the activity of anaerobic sulfur-reducing bacteria and can lead to the formation of harmful acids.

This project, which brings together an international interdisciplinary team of researchers from the University of Sheffield, the University of Copenhagen, Columbia University, the ESRF and the Mary Rose Trust, has applied a new x-ray computed tomography method to unlock detailed information about these deposits.  Applying this method also overcomes the additional challenge of studying precious cultural artefacts where care must be taken to avoid damaging the fragile remains as these experiments can be performed without destroying the sample.

Up to now, it has not been possible to obtain detailed information about the structure of harmful deposits within the wood.  As Professor Cussen explains: “It is remarkable that this technique, available at the ESRF, allows us not only to image and locate these nanoparticles in Mary Rose wood, but also to evaluate their structure.  This is the first time zinc sulfide nanostructures have been observed in Mary Rose wood.  This is because it is really challenging to assess the range of material present within archaeological samples”.

Using the new technique, which combines x-ray computed tomography with pair distribution function analysis (ctPDF), the team has mapped out the location and structure of nanostructured compounds lodged within the ship’s wooden hull.  The team have also uncovered the location of organic polymer deposits within the wood, a result of polymer treatments applied to compensate for degradation of the wood.  If the polymer starts to breakdown, it would produce degrading acids that could damage the Mary Rose - so knowing where the polymer is within the ship’s wood and tracking it over time is crucial to conserving the artefact. 

Professor Cussen added: “These developments mean that potential threats to the wood can be tracked - a vital step in developing conservation strategies for the future of the Mary Rose.  With the insights we have gathered from this experiment we’ve been developing new magnetic nanoparticle-based treatments to target and remove these harmful species from the Mary Rose.  This will help us preserve this priceless artefact for years to come.  This x-ray method could also be used to inform strategies to preserve other important archaeological discoveries.”

Professor Eleanor Schofield, Deputy Chief Executive Officer at the Mary Rose Trust, said: “The application of this technique to complex archaeological materials presents a really exciting advancement for the field of heritage science.  To be able to look inside a piece of Mary Rose wood and see not only the structure but also the level of degradation, previous conservation treatments and other inclusions from the marine environment, is a fascinating insight.  It provides us with a wealth of knowledge which we can use to further understand how the materials will react to certain treatments and environments and from that, devise future conservation strategies to keep them safe for years to come.”

Source: Mary Rose Museum press release

 

Mary Rose Region South East