Scotland's crown jewels are once again on display at Edinburgh Castle after undergoing the most significant conservation work in their history.

The Honours of Scotland, which consist of the Crown, Sceptre, and Sword of State, have held profound historical significance in Scotland for centuries and are the oldest crown jewels in the British Isles and among the oldest in Europe.

They were presented to King Charles earlier this year at the National Service of Thanksgiving and Dedication at St Giles’ Cathedral.

Experts from Historic Environment Scotland (HES) cleaned the Honours to reduce tarnish and remove build-up of dust and grease. Though the Honours are made of enduring materials, their age and historic use has made them very fragile, and much of the cleaning process took place under a microscope to monitor any potential changes in their condition.

The project took place over several months, with individual items taken off display at scheduled points as part of the programme.

The Herald:

Whilst conserving the Honours, the team also conducted analysis through a range of techniques, including X-radiography, portable X-Ray Fluorescence, and optical microscopy.

This scientific analysis has revealed some intriguing new details about the Crown, showing that several gem settings on the Crown have been affixed with different kinds of pins throughout its long life.

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X-radiography will help identify the metals of which these pins were made, which will aid in the understanding of when these repairs took place. The conserved Honours have also been digitally scanned to ensure that online documentation of these important objects is as comprehensive as possible. 

Reed Hudson, Senior Metals Conservator at HES who led the conservation work, said: “The Honours of Scotland are unique among the HES Collections, and we want to ensure they always look their best when visitors come from near and far to see them.

"We undertake regular cleaning and condition checking of the Honours, but this project marks the first time they have undergone such significant conservation work in their long history. 

“It’s very rare that conservators can focus on just one project in this way and being able to spend this much time with the Honours has been a once in a lifetime experience. It has allowed me to really enjoy small details that I might have missed otherwise, like the figures of the saints engraved on the blade of the sword, or the beautiful floral motifs incorporated into the designs of the sceptre and scabbard. 

"We are continually developing our methods of analysis and care to ensure that we are safeguarding our national treasures in the best possible way.

"This project has allowed us to learn more about the Honours and their history, and we hope to share our findings in the new year. Luckily, visitors don't need to wait that long to see the Honours again as they are now back on display together!"