Actually, we have 2, Glass Mountain and the 1 square mile Little Glass Mountain located about 5 miles southwest of Glass Mountain. Quality obsidian, pure black, knaps beautifully. Many boulders along the road on the north edge about the size of a VW bug. If you are driving a Subaru or Yugo take Fix-a Flat and spare tires...the road is a bitch kitty of glass shards.