Obsidian is a naturally occurring volcanic glass that forms when viscous rhyolite magma, which is rich in silica, erupts as a lava flow then cools rapidly. The rapid cooling and high viscosity of the ...

Volcanic glass has been discovered at more than 500 archaeological sites in western Canada. Geologically-speaking, it shouldn’t be there. Now, researchers may have answered how these artifacts made of ...

Q: I’m curious about what the bright white material along Highway 93 cut just north of Contact, Nevada, might be. Is it diatomaceous earth or something else? A: “I know the road cut outcrop of which ...

Volcanic glass tools that are at least 3,000 years old were used for tattooing in the South Pacific in ancient times, a new study finds. The skin-piercing tools could yield insight into ancient ...

I told my dad, Mike, we were going hunting for rocks as we began making our way east on U.S. Highway 20. “No. We’re hunting for glass,” he smirked from the passenger seat. He wasn’t technically wrong ...