This is heritage science…wax seals in context – an interdisciplinary research project

Dr Elke Cwiertnia, Conservation Scientist at The National Archives, introduces a recently completed project that uses heritage science to shed light on the use of wax seals as communication devices.



Although wax seals have been widely studied with regard to their iconography, their materiality and importance as communication devices are still not fully understood. The National Archives (UK), ‘Wax Seals in Context’ project addressed unanswered questions concerning the study of medieval wax seals by investigating their materiality, manufacture and use allowing us to understand better the making and meaning of this important medium of medieval communication.

Image: wax seal of Henry of Lancaster (TNA: E26 / A 60, B series cord E)

Using heritage science (visual examination, material analysis such as XRF), reproduction of recipes for sealing wax and archival evidence the project has focused on English royal and governmental seals of the 12th and 13th centuries.

X-ray fluorescence (XRF) analysis on a wax seal to investigate the elements (which helps to identify the pigments used).
Verdigris (green pigment) in beeswax, after artificial ageing for 3 weeks (colour change on the edges of the pigment).
Reproduction of sealing wax mixture, here: verdigris (green pigment) in beeswax, colour changes due to heating for several hours.


To find out more, please visit The National Archives website.