Polished Obsidian Sculptures have a natural blue or green hue to them. This igneous rock occurs as a natural glass formed by the rapid cooling of viscous lava from volcanoes. Considered as a semi-precious stone, the Polished Obsidian Sculptures will be the perfect tabletop accessory to add to a bookshelf, mantel, or table. We offer these in various sizes in blue and green tones.