6 September 2005: Historic works of art are their own worst enemy
Katharine Sanderson/Dublin, Ireland
The inks favoured by manuscript writers and old masters for centuries have been destroying the works of art they created, claim Slovenian researchers.
Iron gall inks - derived from oak tree galls and vitriol (ferrous sulphate) - are to blame for destroying the Book of Kells, Bach's musical manuscripts, and drawings by Leonardo da Vinci and Michaelangelo, said Jana Kolar from the National and university library, Ljubljana, Slovenia. Kolar and colleagues are now developing a technique to rescue these precious artefacts.
The inks are acidic and the metal ion oxidation processes destroy the surface they are written on. Kolar used proton induced x-ray emission (PIXE) and noted that the name of the inks was misleading: 'We found that there could be as much copper in the ink as iron, and several other metals. And some of them are much more corrosive than iron,' said Kolar, speaking at the British Association festival of science in Dublin.
To rescue the crumbling manuscripts, Kolar teamed up with European preservation project InkCor. 'We designed a proper antioxidant which could stabilise these things,' said Kolar. By applying the alkali halide-containing non-polar heptane solution and artificially aging model manuscripts, Kolar has increased the manuscripts' lifespan by ten times.
The need to rescue these relics is urgent. 'The damage is enormous,' said Kolar, adding that there are kilometres of shelves with manuscripts that are slowly destroying themselves.
This latest rescue remedy is a prototype, and Kolar likens the next stage to a drugs trial. She doesn't see a commercial product being available for at least five years. There are over 300 ink recipes, which all need analysing before Bach and da Vinci can rest in peace, safe in the knowledge that their works are no longer destroying themselves, said Kolar.