Conservators wield some impressive photo-processing skills, in no small part because of the extensive photographic documentation we do in our work. We use our image-processing skills for research purposes, too.
Right now I’m taking multispectral photos of limestone funerary stelae from the Roman Egyptian city of Terenouthis so that I can begin to characterize the pigments that were used to paint them. Pigments reflect, absorb, and/or luminesce ultraviolet, visible, and infrared light in characteristic ways, but capturing a good image of these photo-chemical responses can be challenging.
The stone condition survey is well underway, and I am just floored by the richness and variety of the Kelsey’s stone collection. We’ve got limestone that is packed full of shell fossils (fig. 1), alabaster that has weathered in a way that it looks like a sea sponge … and, best of all, so much of the material comes from sites that were excavated by the University of Michigan. If I had to choose the most exciting artifacts I’ve encountered so far, it would be those from Karanis, Seleucia, and Terenouthis. I’m a self-professed ancient color geek, and an incredible number of these objects still have pigment preserved.
Take the Karanis stone. I’ve seen hefty jar bases that have traces of pigment and ground still in place, and a libation altar decorated with a vivid orange-red pigment (red lead?) barely visible under a thick layer of burial dirt. At least half of the Seleucia sculptures I’ve examined have traces of pink pigment, including one with a highly detailed painted necklace. I’ve spent years studying the Terenouthis funerary stelae, and even these continue to surprise me. I spotted blue-green pigment on a well-preserved stela that I am eager to investigate further (fig. 2).
In addition to revealing the extent of surface decoration on the Kelsey’s collection of stone, the survey is also helping me determine which artifacts are in need of treatment or rehousing. It’s amazing to me how much there is to learn from objects in the collection even now, in some cases nearly ninety years after their discovery.