Horton, the archaeologist for Yellowstone, as she displayed obsidian knives and spear points from the park’s archives. “How did they interact with this landscape? Where did people go to visit?

The Lake County Sheriff's Office says that shortly after an August training one of its deputies located a suspect with a satchel full of spear points, serrated hand tools and obsidian flakes.

Some of the obsidian artifacts, including arrowheads and spear tips, traveled nearly 750 miles from their source, according to Allan. An obsidian spear head from the Red Deer area. Photo by Todd ...

Hand-carved arrowheads and jagged spears made of obsidian, a sharp rock formed by volcanic magma, are remnants of vast prehistoric trade networks that once cut across western North America.

Obsidian is perhaps best known in its role as the dark black blade atop ancient spears and axes – but what if we wanted to add a little bit of pizzaz to our prehistoric weaponry? Look no further ...

Before the days of metal tools, prehistoric hunters worked obsidian into points sharp enough to penetrate animal hides. Many a bison and caribou fell to spears and arrows tipped with obsidian ...