(Measurements by an amateur) Stone: Rainbow Obsidian Diameter: Approximately 6mm Buckyball Diameter: Approximately 5.5cm Rainbow obsidian is said to dispel indecisive emotions and enhance intuition and decision-making abilities. Buckyballs are also called fullerenes, but those not made of natural stone are not called fullerenes. They are called buckyballs. The shape is the same as the pattern of a soccer ball, made up of a combination of hexagons and pentagons. Please display it in your room and enjoy the colors.