Obsidian is volcanic glass with a chemical composition similar to that of rhyolite or granite. It is most commonly black, although greenish to reddish and banded varieties also occur. In addition to its dark color and glassy luster, obsidian is...

Obsidian is a type of naturally-occurring glass formed as an extrusive igneous rock. It is produced when felsic lava extruded from a volcano cools rapidly through the glass transition temperature and freezes without sufficient time for crystal growth....

Idaho State University anthropologists are retracing American Indian trade routes by bombarding arrowheads and other stone tools with radiation that helps locate their origins.The work at the Idaho Accelerator Center in Pocatello involves a process called photon activation analysis. It allows researchers to measure trace...

Archaeologists diving into a lake in the crater of a snowcapped volcano found wooden scepters shaped like lightning bolts that match 500-year-old descriptions by Spanish priests and conquerors writing about offerings to the Aztec rain god.The lightning bolts _ along with cones of copal incense...

Human remains estimated to be more than 10,000 years old that were found in a cave in the Tongass National Forest rightfully belong to the southeast Alaska Tlingit tribes, the federal government said.Now, 11 years after they were found during a U.S. Forest Service archaeological...

When Matthew Kuehne dives to the sandy bottom of Pensacola Bay, he reaches back 450 years to Spaniard Don Tristan de Luna's hurricane-doomed effort to form the first colony in the present-day United States.Archaeologists say the buried hull of a ship from de Luna's fleet...