AAA Grade CZ:
AAA Grade CZ is a manmade stone, in which its refractive index, dispersion and hardness is extremely close to those of a natural diamond. It also creates more flashes of color, giving it a fiery and brilliant appearance.
Rutile is a mineral composed primarily of titanium dioxide. Rutile has among the highest refractive indices at visible wavelengths of any known crystal, and also exhibits a particularly large birefringence and high dispersion. Small rutile needles present in gems are responsible for an optical phenomenon known as asterism. Asteriated gems are known as "star" gems. Star sapphires, star rubies, and other "star" gems are highly sought after and are generally more valuable than their normal counterparts.