Tiger’s Eye

Tiger’s eye is a mineral in the quartz family that is known for its optical effect, called chatoyancy.  The hallmark of the effect is a linear sheen that runs perpendicular to the fibrous structure of the crystal.  The silky, fibrous appearance of the crystal is due to cavities that interrupt the typical quartz crystal structure and are filled with limonite, a type of iron ore.  As a gemstone, tiger’s eye is often cut “en cabochon”, or rounded with a flat base. This method improves the chatoyance.