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Buttressed Stir Sapphire

#1155b7
Notes

Buttressed Stir Sapphire (#1155B7) is a true azure with a cool character. It leans cool, sitting on the blue, green, and violet side of the wheel. Quiet and dependable, a fit for product UI and data visualization. Its HSL profile (215°, 83%, 39%) 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 amber. For something softer, pull in its analogous neighbors on either side of the wheel.

HEX
#1155b7
RGB
rgb(17, 85, 183)
HSL
hsl(215, 83%, 39%)
HWB
hwb(215 7% 28%)
OKLCH
oklch(47.1% 0.168 259.1)
P3
color(display-p3 0.1548 0.3282 0.6928)
HSV
hsv(215, 91%, 72%)
LAB
lab(37.90% 18.66 -57.24)
LCH
lch(37.90% 60.20 288.06)
CMYK
cmyk(91%, 54%, 0%, 28%)

Etymology

Buttressed
adjective

Old French bouterez, thrusting-mass — past-participle of buttress, derived from bouter (to thrust). As a color modifier, buttressed implies a saturated-and-architecturally-supported quality, the deep-rich color of Gothic-Cathedral flying-buttress-and-rib-vault stone-architecture. Sits at the bold-and-fortified end of the grid, parallel to fortified and reinforced.

Stir
modifier

Old English styrian, to-move-or-agitate. As a color modifier, stir implies a slow-moved-and-rippled-and-agitated quality, the visual register of cauldron-and-tea-cup-stir hand-slow-moved-and-rippled-and-agitated cauldron-and-tea-cup-and-pot-au-feu stirred-and-slow-moved-and-rippled-and-agitated surfaces under cauldron-and-tea-cup-and-pot-au-feu kitchen-hearth-and-witch's-fire-and-parlor-tea-table simmer-and-eddy-light. Sits at the modifier-and-mood end of the grid, parallel to swirl and eddy in usage.

Sapphire
noun

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 explore

Harmonies

Accessibility

Color-vision simulation

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.

#1155b7
Original
#0061ba
Protanopia
#0052b5
Deuteranopia
#006d7d
Tritanopia
#4e4e4e
Achromatopsia
WCAG contrast

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.

The quick brown foxSample body text at normal size. The wcag minimum for body contrast is 4.5:1 (AA) or 7:1 (AAA).
AAon White
6.98:1
The quick brown foxSample body text at normal size. The wcag minimum for body contrast is 4.5:1 (AA) or 7:1 (AAA).
AA Largeon Black
3.01:1

Wide gamut

Display P3 representation

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.

sRGB hex
sRGB hex
##1155B7
Display P3
Display P3
color(display-p3 0.1548 0.3282 0.6928)
P3 has subtle headroomOKLCH chroma 0.168

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.

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