iridescence (ĭrˌədĕsˈəns) [key], exhibition of rainbowlike colors on a surface. It usually results from interference when light composed of different wavelengths is reflected from the superficial layers of organic or inorganic substances, e.g., minerals, mother-of-pearl, and the feathers of birds. Iridescence greatly enhances the value of certain gems.
The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved.