Rich Ultramarine
Rich Ultramarine (#18479E) is a true azure with a jewel character. It carries the deep, saturated richness of a gemstone. Authoritative and slightly formal, it works well for type and heavy UI elements. Its HSL profile (219°, 74%, 36%) places it in the balanced band at a mid lightness. It works across type, buttons, and borders, saturated enough to feel deliberate but balanced enough to not fight the rest of the palette. For a confident two-color system, pair it with its complementary amber. For something softer, pull in its analogous neighbors on either side of the wheel.
Etymology
Old French riche, wealthy, abundant — applied to color since the medieval period for hues that read as plentiful in pigment. Rich red, rich brown: the implication is depth combined with saturation, a color that gives the eye more to absorb. Sits at the saturated mid-light corner of the engine's grid, slightly warmer than bold and deeper than vivid.
The pigment ground from lapis lazuli — the Afghan mineral imported through Venice in the late Middle Ages, more expensive by weight than gold during the Renaissance. The color refers to a freshly mixed ultramarine pigment in linseed oil: a saturated, slightly violet-shifted deep blue with the matte finish of micron-ground rock. Deeper than cobalt, cooler than royal, with the art-historical weight of the blue Vermeer reserved for Mary's robe.
Closest matches
The nearest named color in three reference sources, ranked by perceptual distance (ΔE76 in CIELAB). ΔE < 1 is imperceptible to most viewers; ΔE > 10 is clearly different. When two sources point to the same hex they’re merged into one tile; click any to open that color’s page.
Variations
Click any swatch to exploreHarmonies
Accessibility
How this color appears to viewers with the four major color-vision-deficiency types. Computed via the Machado (2009) physiologically-based model. If a tile matches the original, the color reads the same to that viewer.
The color used as foreground text against pure white and pure black, with the contrast ratio and WCAG 2.1 grade. Aim for AA (4.5:1) for body text and AA Large (3:1) for 18 pt+ headlines; AAA (7:1) is the gold standard for long-form reading surfaces.