Sometimes the simplest treatments make the most visible impact! This Eleventh Dynasty (2081-1938 BCE) painted limestone stela from Deir el-Bahari in Egypt had a thick and yellowed coating dating from before it was installed in our Lower Egyptian around 1958. It came off easily by swabbing with acetone, followed by a simple cleaning with a xanthan gum/benzyl alcohol gel to remove any remaining dirt. Plaster from where the edges been set into the gallery wall was carefully chipped away with a chisel. Suddenly, the ibis looked much younger than its 4,000 years!
Many thanks to Tom Stanley, the museum’s Social Media guru, for making this transformational GIF:
These photos illustrate various stages in the conservation treatment of a limestone relief, created around 4,000 years ago at the Egyptian site of Deir El-Bahari. Conservators in the @pennartifactlab removed a modern gloss as they prepared the object for display. pic.twitter.com/bLYGShTYNr
— Penn Museum (@pennmuseum) September 25, 2018
We should note that, in conservation, cleaning is considered an “irreversible” treatment – that is, there’s no putting back what you’ve cleaned away. So we’re always careful to make sure that anything we remove is something that shouldn’t be there. This is especially important when the cleaning process is as dramatic as the one above, since you can’t change your mind once you’ve started! From the way the coating was applied over the break edges, it was clear that it had been put on after the stela was excavated. That meant that the coating could be removed and the ibis will be much nicer to look at when it’s reinstalled in the renovated Egyptian Galleries.