Cat's eye stone is made of chrysoberyl.

Cat's eye stone, that is, "with the cat's eye effect of chrysoberyl". Also known as "cat's eye", "cat's eye", "cat essence", Oriental cat's eye, is a rare and valuable variety of jewelry variegated stone cat's eye also known as Alexandrite cat's eye, that is, there is a variegated color and cat's eye phenomenon.

Cat's eye is the rarest and most precious type of chrysoberyl, the world's only Sri Lanka, the price is quite expensive, more than 10 carats of domestic shopping malls is difficult to see. Because the cat's eye stone shows the phenomenon of light and cat's eyes, flexible and bright, with the intensity of light and change, so named. This optical effect, known as the "cat's eye effect".

Cat's eye stone in mineralogy is a kind of chrysoberyl, belongs to the chrysoberyl family of minerals. Chrysoberyl is a beryllium-containing aluminum oxide, chemical molecular formula for BeAl2O4. is a rhombohedral crystal system. The crystal form is often short columnar or plate-like.

Strictly speaking, "cat's eye" is not the name of the gemstone, but an optical phenomenon on some gems. That is, ground into a hemispherical gemstone with strong light, the surface will appear a thin narrow bright reflection, called "cat's eye flash" or "cat's eye live light", and then according to what the gemstone is named, if the gemstone is quartz, it is called If the stone is quartz, it is called "quartz cat's eye", and if it is chrysoberyl, it is called "chrysoberyl cat's eye".