Swirly flow lines of volcanic glass (obsidian) within a piece of lava at Mount Lokon volcano near Tomohon city, Gunung Lokon, Tomohon, North Sulawesi, Indonesia, Southeast Asia, Asia

Obsidian knife on display at the Egyptian Museum, Cairo, Egypt, North Africa, Africa

Moraine lake on the Obsidian Flow lava stream, Newberry National Volcanic Monument, Oregon, USA