Rockhounding Site: Glass Butte
Rock Type: varied obsidian
Site Description: Glass Butte offers rockhounds a wide variety of gem quality obsidian. Rainbow, black, pumpkin, mahogany, midnight lace, gold sheen, silver sheen, fire, and double flow varieties can all be found in the area. While many rockhounds choose to dig for preferred material, plenty of obsidian is readily available for collection on the ground surface.
Directions: Available on Central Oregon Rockhounding Map, Purchasing Info
Road Access: Not Maintained
Site Information: Muddy when wet. 4x4 vehicle recommended.
Agency: Bureau of Land Management
Obsidian from Glass Butte. Obsidian types clockwise from upper right are rainbow, black, pumpkin, mahogany, gold sheen, and double flow. The center piece is also gold sheen.
Glass Butte is a volcano that formed about 4.9 million years ago and is part of series of volcanic domes that are aligned in a northwest direction. Most of Glass Butte itself is composed of rhyolite flows. In the low lands about 3 miles east of Glass Butte and on Little Glass Butte 4 miles to the southeast, several eruptions produced the obsidian flows that rockhounds collect from today.