As early as 10,000 years ago, the Tahltan First Nations people, who now live in Dease Lake, Telegraph Creek and the Iskut, used obsidian from the Mount Edziza volcanic complex to make tools and weapons for trading material. Most of the obsidian occurs at relatively high elevations at about . This is the main source of obsidian found in northwestern British Columbia, which was traded as far away as Alaska and northern Alberta. Obsidian is a type of naturally occurring glass that is highly valued for its cutting qualities and is produced by the rapid cooling of lava. Like all glass and some other types of naturally occurring rocks, obsidian breaks with a characteristic conchoidal fracture, creating razor sharp edges. A knife made of Edziza obsidian, possibly 2,000 years old, has been recovered in the Stikine River area. Two exposed columnar basalt formations exist within the volcanic complex: the Tahltan Eagle at the meeting of the Tahltan and Stikine rivers, and Pipe Organ Mountain. The Tahltan Eagle has significant spiritual and cultural importance to the Tahltan people, while the correct name and cultural significance of Pipe Organ Mountain to the Tahltan people is unknown.