Iridescence | Optical Phenomenon Caused by Reflections
Iridescence is an optical phenomenon whereby the colours on a surface appear to change depending on the angle at which they're viewed or the angle at which they're illuminated. Iridescence is caused by multiple reflections in multi-layered, semi-transparent surfaces.
Examples of materials that exhibit iridescence include soap bubbles, the wings of a butterfly and certain rocks and minerals. Mother of pearl, rainbow moonstone and labradorite are particularly well known for being iridescent.
The butterflies in our photo are on display in the Harvard Museum of Natural History, Cambridge, Massachusetts, USA. Photo by Stone Mania ©. Clicking the image redirects to the original full size photo.