Unyielding Cast Cerulean
Unyielding Cast Cerulean (#047CCE) is a true azure with a vibrant character. It holds its own as a focal accent, carrying visual weight without tipping into neon territory. Its HSL profile (204°, 96%, 41%) places it in the highly saturated band at a mid lightness. Best used in small doses, like logos, CTAs, focus rings, or highlight text, where its saturation becomes a feature rather than noise. For a confident two-color system, pair it with its complementary orange. For something softer, pull in its analogous neighbors on either side of the wheel.
Etymology
Old English un- (negation) plus gildan (to give-up). As a color modifier, unyielding implies a saturated-and-uncompromising quality where the hue refuses to fade-or-shift under any visual pressure. Sits at the bold-and-resilient end of the grid, parallel to indomitable and adamant in usage.
Old Norse kasta, to-throw / to-mold. As a color modifier, cast implies a poured-metal-and-shaped quality, the visual register of foundry-cast-iron-and-bronze hand-poured-and-cooled iron-and-bronze-and-tin foundry-cast-and-shaped surfaces under foundry-cast-iron-and-bronze workshop-light. Sits at the modifier-and-texture end of the grid, parallel to forged and hewn in usage.
From the Latin caeruleum, originally referring to dark blue paint pigment of the Roman world, then via French céruléen into English. As a modern art-supply name, cerulean blue is the cobalt-tin oxide pigment introduced in 1805. The color refers to a clean, slightly green-shifted blue with the matte finish of mineral pigment in linseed oil: lighter than cobalt, deeper than aqua, with the painter's weight of a word for sky.
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.