We’re celebrating Halloween tonight in the Artifact Lab as part of Yelp’s Night by the Nile event.
To get into the spirit, Lynn and I will be working late, in costume, and talking to guests about conservation and mummies.
We thought that for tonight’s event, it would be appropriate to lower the lights and do some ultraviolet (UV) examination of objects, and to talk about this process to those who visit the lab.
As we have explained in previous posts, visual examination is a critical first step of the conservation process. We can understand a lot about objects just by looking at them under good lighting and with magnification.
While most of our examination is initially carried out under visible light, we also use UV lamps (better known as black lights) to examine artifacts in order to make visible things that we cannot see otherwise. Examination of objects in the dark under UV allows us to see UV fluorescence of materials, and some materials exhibit unique or characteristic fluorescence. This often helps us characterize materials and to distinguish old restoration materials from original materials-for instance, shellac, used historically to repair objects, exhibits a characteristic bright orange fluorescence under UV.
For a great explanation of UV, along with some interesting images, check out this post on UV examination by my colleague Allison Lewis, conservator at UC Berkeley’s Phoebe A. Hearst Museum of Anthropology.
We’ll be sure to share any interesting images we capture tonight!