The latest blog in our British Science Week 2020 is written by Meghan Godley.
This is the first in a series of blogs which we will post over the next few days from Historic Environment Scotland, each of which will showcase the work of a different department.
My background is in geology having just graduated from my master’s geoscience degree. My research looked at the geochemistry and petrology of the Ross of Mull granites, which is one area of geology that I have a very strong inclining towards. On completion of my degree I was interested in expanding my laboratory skills in a whole new sector. I always had a passion with history and heritage, so this was the perfect mix while I can still progress my learning.
The conservation science traineeship provides an excellent opportunity of experience and training in a range of materials testing and different analytical techniques, targeted towards understanding the behaviour of building materials regarding future conservation challenges, including the threats of climate change. One issue that we face when conserving our traditional buildings concerns the sourcing and replacement of historic roofing slate.
By using a piece of equipment known as a chromameter we were able to quantify the colour of different historic slates and use this information to help identify the original source region of the slates and the most appropriate replacement slates to be used.
By undertaking scientific analysis of traditional building materials and conducting on-site condition monitoring, the conservation science team supports the making of informed conservation decisions in order to protect HES’s properties in care.
One technique we use is X-ray Diffraction (XRD) analysis, which uses X-rays to determine the minerals present in a material. This technique was used to understand the composition of repair material to a window in the King’s Old Building’s at Stirling Castle. We identified that the material was made from a lime putty and contained several layers of paint, which contained white lead. Health and safety precautions were then put in place to ensure the safe removal of the material.
Having studied geology at university, I never thought that I’d ever be analysing the composition of glass! Recently Dr Maureen Young and I were asked to analyse some glass window panes from Edinburgh Castle to help determine their age. By using a technique called X-ray Florescence (XRF) we can measure the chemical composition of the glass. By identifying specific elements within the material, we can help date the glass, according to the changing manufacturing processes used in Scotland. The panes dated to post 1930’s, indicating the glass had been replaced during repairs to the windows recorded at this time.
By utilising these newly learnt skills, I’m now conducting my own research project concerning the characterisation and potential climate-change impacts on the Achnabreck rock carvings in Argyll. This site provides some of the best examples of prehistoric rock art in Scotland. By better understanding the composition of the geology at these sites, we can help mitigate the risk to the threats of climate change and help preserve their conditions for future generations.