A collection of pictures from Restoration Hardware Nathan Dehart: Obsidian Obsidian is formed when molten lava cools quickly, sometimes mixing with other materials in the process. Nathan DeHart creates abstract geological studies of the protrusions, where this mixture is the most dramatic. The stone is covered with honey tones and is spotted with white, rough exterior textures, contrasting with glass black spots. The model in 2011 (V-Ray) + obj.