Hefty Vesper Sapphire
Hefty Vesper Sapphire (#3551B9) is a true blue with an earthy character. It leans grounded and natural, the kind of color that plays well with wood, clay, linen, and warm neutrals. Its HSL profile (227°, 55%, 47%) 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 English hefig, heavy — adjectival suffix -y. As a color modifier, hefty implies a saturated-and-substantial-and-weighty quality where the hue carries the visual heft of a hand-cast pig-iron object. Sits at the bold-and-weighty end of the grid, parallel to substantial and weighty in usage.
Latin vespera, evening. As a color modifier, vesper implies an evening-prayer-and-dusk quality, the visual register of Roman-Catholic-and-Orthodox-Vespers evening-prayer-and-dusk hour-of-day evening-prayer-and-incense liturgical surfaces under Vespers-and-Compline ecclesiastical-evening candlelight. Sits at the modifier-and-time end of the grid, parallel to eve and knell in usage.
An iron-and-titanium-bearing corundum — the same mineral as ruby, hardness 9 on the Mohs scale, mined for two millennia from Sri Lanka, Burma, Madagascar, and the Cashmere mines of British India. The color refers to a fine Kashmir-cut sapphire: a saturated, slightly violet-shifted deep blue with the gem's signature internal velvet — a quality of light scattering in the stone that faceted glass cannot replicate. Cooler than cobalt, deeper than azure.
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.
Wide gamut
The CSS Color 4 wide-gamut form of this color. Both swatches render the same color on every display — the P3 form only diverges from sRGB when a designer pushes channels outside sRGB's reach.
Moderately saturated colors gain a small bump in P3 — the difference is usually visible side-by-side on wide-gamut hardware but won't change the character of the color.