Obsidian mahogany. Igneous rock. Rotation on a dark background. Ornamental stone. Jumping From Cliffs to Rough Water Below Maui, Rocky Coast - Seashore obsidian stock videos & royalty-free footage ...

Obsidian is a volcanic glass formed when silica-rich lava cools so fast that crystal formation is only visible with a microscope. The glassy and amorphous nature of obsidian makes it hard and brittle.