California Rainbow Obsidian Is a Natural Wonder (Amazing Photos)

Obsidian is dense volcanic glass, usually rhyolite in composition and typically black in color. Obsidian with multicolored iridescence caused by inclusions of magnetite nanoparticles. Obsidian is often formed in rhyolite lava flows where the lava cools so fast that crystals do not have time to grow.

The volcanic deposits found in the Warner Mountains come in many forms. From the light weight pumice sometimes called "floating rocks" to the dense, glass-like obsidian, the colors and diversity are amazing. The Warner Mountains are famous for the variety of obsidian and for the four mines where the public can, with a permit, collect it.(Peppermint stripe Obsidian from Davis Creek. photo: Scott's Rock & Gem)