14 DAY TRIAL // Forensic crime lab techniques will be employed for hunting dyes, paint, and other decoration in prehistoric textiles.
Ancient fabrics give many details about a specific culture, but usually their coloration is faded, patterns dissolved, and fibers crumbled.
A team at Ohio State University believes that forensic photography technique would be a cheap and non-destructive method to analyze ancient artifacts. This method is used for prevailing evidence, before expensive chemical tests damage a sample material. "Normally when you dig artifacts out of the ground, especially stone or ceramic ones, you wash them and they look sexy. But you can't do that with textiles," said Christel Baldia, Ohio State University doctoral graduate in textiles and clothing.
Using this method, the researchers studied textiles from burial mounds left by the Hopewell, a developed prehistoric Native American culture in eastern/central US that vanished 16 centuries ago, specifically materials found in Seip burial mounds from southern Ohio (photo). "Textiles often come out looking like brown rags, yet Native American dress is described as colorful by early travelers or pioneers." said Baldia.
Forensic research employs different light waves, from ultraviolet to infrared, to visualize stains or fingerprints on clothing. The non-visible lights can reveal hidden clues on faded or deteriorated textiles, because many pigments and dyes are fluorescent, reflecting non visible waves in the visible spectrum.
UV and IR light helped the researchers watch previously unseen patterns and markings in some of the ancient artifacts. "The materials we examined from Hopewell burial mounds show gradations of color under different light sources," Jakes said. "When artifacts have non-random changes in color like that, it indicates to us that there has to be dye or pigment. That's significant for ancient textiles because it reveals technologies prehistoric Native peoples were capable of."
"The code of ethics from the American Institute of Conservation is 'do no harm'," said Kathryn Jakes, professor of textile sciences in the College of Education and Human Ecology at Ohio State.
"For the artifact to stick around for as long possible, you have to be as minimally destructive in your sampling as possible."
Classic archaeological methods of investigating ancient textiles require removing a fiber. "People essentially do this randomly, but forensic photography helps minimize damage by enabling us to sample strategically," Baldia said. "If archaeologists see a pattern in forensic photographs, then the area most likely contains dye or paint-and focusing on such areas ultimately provides more information about ancient civilizations while cutting research costs."
The researchers came with the idea of employing forensic photography for researching ancient fabrics from museum painting conservators. "Art museums use it to see if a painting has been painted over, if it's a forgery, and so on," Baldia said. "We thought: 'why aren't we doing this with ancient textiles?'"
The team would like to see this technique also applied to other organic artifacts, such as leather or wood.
Photo credit: The Journal of Archaeological Science , Vol. 34.