Shiny and sharp, obsidian is enjoying a bit of a pop culture moment. It plays a central role in HBO’s hit fantasy series Game of Thrones, now wrapping its final season. Called dragonglass on the show, obsidian is one of only two substances that can cut down White Walkers, malevolent otherworldly warriors.
In the real world, the volcanic glass reveals the human story in a way no other material can.
Our evolutionary ancestors used obsidian for toolmaking for more than a million years. Thanks to the material’s unique chemical attributes, archaeologists can determine the geographical origin of even small pieces. But that’s only part of the story.
Arizona State University archaeological scientist Andrew Zipkin says knowing where our distant ancestors collected obsidian allows researchers to ask much broader questions, such as where early humans traveled, and why.
“It’s easy to source obsidian and determine where it came from, but that’s only the first step, because that’s chemistry, not archaeology,” says Zipkin. “The ultimate goal is to understand what motivated these people to collect it from that location.”
