Answer: chatoyant

AnswerCrossword Clue
chatoyantchanging in luster or color.
chatoyantreflecting a single streak of light when cut in a cabochon
chatoyant(French) having a changeable luster like that of a cat's eye at night / a chatoyant gemstone, such as a cat's eye
chatoyantcabochon-cut gemstone having this reflected streak, as a chrysoberyl cat's-eye
chatoyantchanging in luster or color