Why are some natural colours produced by pigments and others by structure?
Pigment colour comes from chemical compounds that absorb some wavelengths of light and reflect others; structural colour comes from microscopic physical structures that interfere with light directly, without any pigment involved. Both mechanisms are common in nature, and some organisms combine both in the same colour.
Domain: AnimalsDomain: PlantsDomain: MineralsMechanism: Biological pigmentMechanism: Mineral pigmentMechanism: Structural colour
There is no blue pigment anywhere in this wing. Microscopic ridges on each scale split and reflect light so that only blue wavelengths reach the eye — the same physical principle behind a hummingbird's gorget or a peacock's tail.
Whole-frame automated colour extraction on this photograph is dominated by the dark background and shadow between the wings, not the wings themselves — these hexes were hand-picked from the wing surface instead."Blue Morpho" by Derkarts, CC BY-SA 3.0, via Wikimedia CommonsLicence details
- Source:
- Wikimedia Commons
- Creator:
- Derkarts
- Licence:
- CC BY-SA 3.0 (also offered under 2.5/2.0/1.0 and GFDL) — free to share and adapt commercially, provided the work is attributed and any adaptation is shared under a compatible licence.
- Reviewed:
- 2026-07-24
Unlike the sky's or a butterfly wing's structural colour, poppy red comes from anthocyanin pigment in the petals — a genuinely different mechanism producing a superficially similar bright, saturated colour.
Poppy petals are thin and translucent, so their apparent red shifts noticeably with backlighting; this photograph was taken in flat, even daylight."Close up red wild poppy flowers" by Dusan Bicanski, public domain, via Wikimedia CommonsLicence details
- Source:
- Wikimedia Commons
- Creator:
- Dusan Bicanski
- Licence:
- Released into the public domain by the copyright holder, free for any use.
- Reviewed:
- 2026-07-24
How this colour is made
Biological pigment
A molecule in the tissue absorbs some wavelengths of light and reflects others — the reflected wavelengths are the colour seen. Chlorophyll, carotenoids and melanin are the most common examples.
Common misconception: Not every vivid natural colour is a pigment — several of the most striking blues and greens in animals are structural colour instead, which looks similar but works completely differently.
Mineral pigment
Trace metal ions or compounds within a mineral's crystal structure absorb specific wavelengths of light, giving the mineral its characteristic colour — the same chemistry behind natural earth pigments like ochre.
Structural colour
Microscopic physical structures — ridges, layers or particles smaller than the wavelength of light — interfere with light waves so that only certain wavelengths are reflected back. No pigment is involved at all.
Common misconception: A structurally-coloured feather or scale ground into powder loses its colour completely, because grinding destroys the microscopic structure that produced it.
Pigment colour results from a chemical compound absorbing specific wavelengths of light and reflecting the rest — the compound's molecular structure determines which wavelengths are absorbed, and therefore which colour is seen.
Animals · confidence: high
Structural colour results from physical structures at a scale comparable to the wavelength of light — such as thin layers, ridges or lattices — that reflect and interfere with light waves, reinforcing certain wavelengths regardless of any pigment present.
Animals · confidence: high
Some organisms combine both mechanisms in the same colour — for example, many green animals use a yellow pigment layered beneath a blue-reflecting structural layer, with the two combining to appear green even though no green pigment is present.
Animals · confidence: medium
Structural colour and iridescence are closely related but not identical: structural colour describes the general mechanism, while iridescence specifically describes a structural colour that visibly shifts hue with viewing angle.
Animals · confidence: high
Related colour profiles
Practical applications
Related questions
Frequency and rarity claims above are scoped to a specific domain, geography or taxonomic group — none are presented as a single universal ranking. See methodology.