Rhyolite

==Rhyolite is an igneous rock. The texture of rhyolite is from glassy to aphanitic to porphyritic. The name came from a german traveler and geologist named Fredinard Von Richthofen. Rhyolite that cools to quickly will grow crystals to form a natural glass or vitrophyre called Obsidian. The texture of Rhyolite is from glassy to aphanitic.==