Iridescence
A shifting, rainbow-like colour effect that changes depending on the viewing angle.
Technical definition
Usually produced by structural colour — thin-film interference or diffraction from microscopic surface structures — rather than pigment, so the perceived hue changes with viewing and lighting angle.
Common confusion
Iridescence is not the same as a simple metallic paint finish, though metallic finishes can look superficially similar.
Example
Soap bubbles, some beetle shells and certain butterfly wings show iridescence.
Why it matters
Iridescent finishes and structural colour behave differently under changing light than flat pigment colours — see Colour in Nature for real examples.
Related terms
Sources
- Colourwise editorial synthesis — Colourwise