Obsidian • silver

Obsidian is a naturally occurring volcanic glass that forms when lava extruded from a volcano cools rapidly with minimal crystal growth. It is an igneous rock. It is usually found on the rim of rhyolitic lava flows known as obsidian flows. Obsidian is hard, brittle, and amorphous; therefore, it breaks with sharp edges. Its color is mostly black, snowflake obsidian has gray inclusions, mahogany obsidian is mostly brown, other rarer versions have a silvery or golden sheen (silver/golden obsidian).