Leonardo's Own Words
"The first of all simple colours is White, though philosophers will not acknowledge either White or Black to be colours; because the one is the cause of colours, the other is the total absence of them."
Treatise on Painting, Chapter CCIIILeonardo identified six "simple colours" — what he considered the fundamental building blocks of all visible hue. They were: white, yellow, green, blue, red, and black. He debated internally whether black and white qualified, calling white "the cause of colours" and black "the total absence of them."
This list is remarkable not for its completeness (Newton's spectral theory was 200 years away) but for its practical accuracy. Yellow, green, blue, and red form a workable primary-plus-secondary palette that anticipates modern pigment mixing far better than contemporary treatises.
Color Perspective
Leonardo's most original color contribution was integrating hue into his perspective of disappearance (aerial perspective). He catalogued precisely how each colour changes over distance:
| Colour | Near | Medium Distance | Far Distance |
|---|---|---|---|
| White | True white | Pale blue tint | Merges into sky blue |
| Yellow | Vivid yellow | Loses saturation, greens | Becomes greenish-grey |
| Red | Vivid red | Weakens, shifts warm | Fades to brown/grey |
| Green | Vivid green | Shifts toward blue | Becomes blue-grey |
| Blue | True blue | Retains hue longest | Lightens toward sky |
| Black | True black | Dark grey-blue | Becomes pale blue |
His core insight: every colour approaches blue at great distance, because the intervening particles of atmosphere scatter short-wavelength (blue) light. He could not name it, but he had intuited Rayleigh scattering — the physics behind blue skies — three centuries before Lord Rayleigh's formal explanation in 1871.
Color Interaction
"Of different colours equally perfect, that will appear most excellent which is seen near its direct contrary: a pale colour against red, a black upon white… blue near yellow, green near red."
Treatise on PaintingLeonardo observed simultaneous contrast — colors appear more vivid when placed next to their opposites. His pairings (blue/yellow, green/red) are precisely the complementary pairs that Chevreul would formally describe in De la loi du contraste simultané des couleurs in 1839, and that the Impressionists would later exploit systematically.
Colored Reflections
He insisted that surfaces are never a single flat colour, because they always absorb reflected colour from their surroundings. A green meadow tints the shadowed underside of a chin green. A golden wall throws warm light onto a nearby white surface. He wrote: "No colour is seen just as it really is, unless the light by which it is illuminated is of the same colour."
In Leonardo's Works
The Last Supper
Before deterioration and over-painting, the Last Supper displayed a symphony of symbolic colour assignments. Christ's garments were red (humanity) and blue (divinity). Judas wore green (jealousy, decay). The tablecloth was white. The 2019 RAI/Uffizi digital reconstruction restored these contrasts, revealing that Leonardo had arranged complementary pairs across the composition — blue apostles against gold-lit walls — creating the simultaneous contrast he described in his writings.
Mona Lisa
The most muted colour palette in Leonardo's career. X-ray fluorescence analysis shows he used only a handful of pigments: lead white, bone black, raw umber, yellow ochre, and a vermilion-lake mixture for the lips. The background landscape demonstrates his colour recession theory — warm browns near the shoulders shift through green midtones to cool blue mountains merging with the sky. It is a textbook demonstration of colour perspective in a single painting.
Ginevra de' Benci
Leonardo's earliest surviving portrait shows him already experimenting with natural colour. The juniper tree behind the sitter is painted with exacting botanical accuracy — deep green needles, reddish-brown bark, blue-grey sky through branches. The skin tones are cool and pale, using minimal warm colour to capture Ginevra's legendarily pallid beauty. Compare this restrained palette with the vivid, enamel-like colour of his master Verrocchio, and Leonardo's move toward naturalism over decoration is immediately visible.