Sometimes it’s not the work itself but the materials we use to display it that need help. In this post, photograph conservator Katy Whitman describes how she fixed a pesky case of glass deterioration.
The problem: This is an excellent example of the crystal form of glass deterioration, which is caused when impurities in the glass are combined with adverse environmental conditions over time. It can show up as weeping droplets or crystals, as seen in the “before” picture above. In advanced cases of glass deterioration, the glass will actually become cloudy and translucent.
The treatment: I removed the daguerreotype plate package from the case and then disassembled it. I cleaned the cover glass and then spot-treated the image plate to remove fallen crystals and mould deposits. Finally, I reassembled the package and re-affixed the original sealing tape to the plate package.
The goal when treating daguerreotypes and other cased photographs is to retain as much of the original material as possible. Because the original glass had not reached a “cloudy” state of deterioration, I judged that it could be cleaned and replaced in the plate package.
About the daguerreotype:
William Edward Kilburn,(British, active 1846-1862)
[Portrait of Young Gentleman with Cravat] c. 1845
Daguerreotype, tinted: ¼ plate, cased in brown leather with red velvet interior
Overall (Image) 8.2 x 7 cm; Image 8.2 x 7cm
Gift of John Richmond Harris
© 2013 Art Gallery of Ontario
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