Editing Variegation (section)

=== Structural ===

Some variegation is caused by [[Structural coloration|structural color]], not pigment; the microscopic structure of the plant itself reflects light to produce varying colors. This can happen when an air layer is located just under the [[Epidermis (botany)|epidermis]] resulting in a white or silvery reflection.<ref>{{Cite journal |last1=Konoplyova |first1=Aelita |last2=Petropoulou |first2=Yiola |last3=Yiotis |first3=Charilaos |last4=Psaras |first4=George K. |last5=Manetas |first5=Yiannis |date=2008-11-01 |title=The fine structure and photosynthetic cost of structural leaf variegation |url=https://www.sciencedirect.com/science/article/abs/pii/S0367253008000807 |journal=Flora - Morphology, Distribution, Functional Ecology of Plants |volume=203 |issue=8 |pages=653–662 |doi=10.1016/j.flora.2007.10.007 |bibcode=2008FMDFE.203..653K |issn=0367-2530|url-access=subscription }}</ref> It is sometimes called blister variegation.{{Citation needed|date=November 2024}} [[Pilea cadierei|''Pilea'' ''cadierei'']] (aluminum plant) shows this effect. Leaves of most ''[[Cyclamen]]'' species show such patterned variegation, varying between plants, but consistent within each plant. 

The presence of hairs on leaves, which may be coloured differently from the leaf itself, can also produce variable coloration. This is found in various ''[[Begonia]]'' species and their hybrids. 

Sometimes venal variegation occurs – the veins of the leaf are picked out in white or yellow. This is due to lack of green tissue above the veins. It can be seen in some [[Araceae|aroids]]. The [[Silybum marianum|blessed milk thistle]], ''Silybum marianum'', is a plant in which another type of venal variegation occurs, but in this case it is due to a blister variegation occurring along the veins.