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Skip to 0 minutes and 11 seconds Susie Bioletti is keeper of conservation and preservation in a library at Trinity College. Over the past few years, she’s been conducting research into the inks and pigments made to create early Irish manuscripts. The brilliance of the colours in the Book of Kells has fascinated people through the centuries, and there’s been a lot of discussion about what those products might be. So coming to the present day, we’re really fortunate in that we have technologies available now to use for manuscripts such as the Book of Kells, which are absolutely nondestructive and noninvasive. So here in Trinity, the two techniques that we’ve had available have been Raman spectroscopy, which is widely used for pigment analysis. And we also use X-ray fluorescence.

Skip to 0 minutes and 55 seconds In combination, they’re quite powerful tools because you can support the evidence you get from one piece of equipment with the results from another. And both of them are used directly onto the manuscript, and we get instant results. They’ll tell us information about the chemistry of the pigment, and from that, we then have to do some detective work in matching the chemical profile back to the colour. So at the end of the work that we’ve carried out here, we’ve narrowed the pellet down to 10 pigments. So the pigments that we have on the manuscript have been created from a number of different products, from dye stuff extracted from plants, from minerals that have been ground and pulverised.

Skip to 1 minute and 36 seconds And they’ve also been created or manufactured from products and transformed into another product. So we have lichen producing a purple pink dye, which is identified on the manuscript as our principal purple. The dye would have to be extracted from this. So the principal ink is an ink known as iron-gall ink and this was created by extracting a gallotannic acid from an oak apple. And that would have been pulverised and soaked in water, then mixed with iron sulphide. And as it oxidises, a beautiful link is formed, which has a range of tones from quite warm brown to warm black. And along with a few other pigments, this black is the principal ink.

Skip to 2 minutes and 25 seconds The brilliant yellow throughout the manuscript is in all cases a product called orpiment. It’s a mineral pigment, and it’s incredibly toxic. The vibrant yellow is used in a manner that gold perhaps would have been used. Gold was used at this time on manuscripts. However, we have no gold used on this manuscript. It’s the sheer brilliance of the orpiment that replicates the gold effect.

Pigments in the Book of Kells

The vibrancy, beauty, application and combinations of colour in the Book of Kells has fascinated viewers through the centuries.

Determining what materials were used requires analytical work. We can only use non-destructive techniques as we have a policy of non-sampling, so the techniques need to be safe to use directly on the manuscript.

Originally it was thought that up to thirty different pigments were used, but we have narrowed down the number and discovered the very clever use of a small number of plant- and mineral- based pigments which are mixed with white to lighten them, or with extra binder to make them glossier, or layered to create the rich and colourful impression conveyed by the manuscript today.

Pigments: Carbon Black, Iron Gall, Red Lead, Orpiment, Gypsum, Indigo, Orecin, Verdigris Some of the most extensively used pigments in the Book of Kells (Bioletti et al. 2009).

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The Book of Kells: Exploring an Irish Medieval Masterpiece

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