Analysis by X-ray of three copper-alloy artefacts recovered from the wreck of the Mary Rose has offered new insight into their construction and the success of conservation efforts undertaken on them.
Henry VIII’s flagship, the Mary Rose, was constructed in 1509 and sank in the Solent on 19 July 1545, during a battle with a French invasion fleet. The remainder of the ship’s hull was raised in 1982 (see CA 85 and 272), and is now housed in the Mary Rose Museum, along with many of the 19,000 artefacts recovered from the wreck. Since then, the ship has been the subject of numerous investigations, from DNA analysis and facial reconstructions of the skeletons of its crew (CA 352) to the use of new technology to conserve its cannonballs (CA 337). In this latest study, published in the Journal of Synchrotron Radiation (https://doi.org/10.1107/S1600577520001812), X-ray analysis was used to examine three artefacts believed to be brass links from chainmail worn by the crew, which were recovered from the wreck in 1981 and 1982.
The research was led by the Universities of Warwick and Ghent, using the X-ray Materials Science (XMaS) beamline. XMaS is a facility owned by the Universities of Liverpool and Warwick, located in Grenoble, France, at the European Synchrotron Radiation Facility. The team used several X-ray techniques, including Synchrotron X-ray Diffraction (XRD), to analyse the surface chemistry of the links from the Mary Rose.
This analysis demonstrated that the links had been made from an alloy of 73% copper and 27% zinc, indicating that Tudor brass production was well-controlled and fairly advanced. Researchers were surprised by the consistent zinc content between the wire links and the flat ones, which suggests a relatively modern alloy composition.
High-sensitivity analysis revealed traces of heavy metals such as lead and gold on the surface of the links. These metals do not appear to be part of the alloy, so it has been suggested that they could have been transferred during manufacturing from tools that were also used to work heavy metals. However, it is possible that the heavy metals were picked up while the wreck was in the water: lead, mercury, and cadmium were present in the Solent after the bombing of Portsmouth Dockyard during the Second World War, and lead and arsenic are also known to have arrived from other rivers over multiple historical periods.
In addition, analysis of the surface chemistry of the links was used to assess and compare the levels of corrosion on all three artefacts, which had undergone different cleaning and conservation treatments after their recovery. It was found that all of the methods used had been effective at preventing corrosion, indicating that the most basic treatment – using distilled water to remove chlorine, followed by storage at reduced temperature and humidity – was sufficient, even over a period of 30 years.