Obsidian is a volcanic glass classed as a mineraloid, and is composed of approximately 70 % Silica, SiO2, This Apache tear variety is formed as as the result of the differential cooling of siliceous, rhyolitic lava flows. The grey mineral surrounding the obsidian is perlite, an amorphous volcanic glass. The name Apache tear is attributed to an Apache legend. Apaches were fighting U.S. cavalry on a mountain overlooking Superior in Arizona. With no hope of winning they rode their horses off the mountain, and their families shed tears which turned to stone on hitting the ground. There are six towns named Superior in the U.S.,and this specimen comes from Superior, Colorado.