Obsidian 1.51 ct

This offered perfectly transparent obsidian is unique because normally obsidian is completely opaque. Obsidian (also known as volcanic glass) is an effusive rock that is formed as a result of magmatic activity, when hot acidic and viscous lava rapidly contacts a cold environment and then solidifies rapidly. Obsidian is very rich in SiO2 compounds and is a natural form of glass. This offered obsidian comes from Gyumush-Dzharaber in Armenia.