ChatoyancyFrom Wikipedia, the free encyclopedia
In gemology,
chatoyancy (pronounced /ʃəˈtɔɪənsiː/, shə-TOY-ən-see), or chatoyance, is an optical reflectance effect seen in certain gemstones. Coined from the French "œil de chat," meaning "cat's eye," chatoyancy arises either from the fibrous structure of a material, as...