1. plural of chatoyancy; the optical effect in certain gemstones (such as cat's eye or tiger's eye) that produces a bright band of light moving across the surface when the stone is turned, resembling the eye of a cat
Usage: technical term used in gemology and jewelry; singular form is chatoyancy

Examples

• The jeweler examined the chatoyancies in the tiger's eye stones to determine their quality.
• Chatoyancies are highly valued in gemstones because they create a striking visual effect.
• The cat's eye chrysoberyl displayed beautiful chatoyancies when rotated under the light.
• Gemologists study chatoyancies to authenticate and grade precious stones.
• The chatoyancies in the moonstone made it a popular choice for the engagement ring.