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Hadean Tarbuttite

#31367b
Notes

Hadean Tarbuttite (#31367B) is a deep 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 (236°, 43%, 34%) places it in the balanced band at a dark lightness. It works well as a headline, icon, or deep background in an otherwise light layout, pairing cleanly with cream, bone, and warm neutrals. For a confident two-color system, pair it with its complementary yellow. For something softer, pull in its analogous neighbors on either side of the wheel.

HEX
#31367b
RGB
rgb(49, 54, 123)
HSL
hsl(236, 43%, 34%)
HWB
hwb(236 19% 52%)
OKLCH
oklch(36.9% 0.116 276.0)
P3
color(display-p3 0.1958 0.2111 0.4656)
HSV
hsv(236, 60%, 48%)
LAB
lab(25.92% 20.13 -40.11)
LCH
lch(25.92% 44.87 296.65)
CMYK
cmyk(60%, 56%, 0%, 52%)

Etymology

Hadean
adjective

Greek Hadean, of Hades — adjectival form of Hades. As a color modifier, hadean implies the deep cool-darkness of the classical-Greek underworld realms, with literary-poetic register. Sits at the deep-and-cool end of the grid, parallel to plutonian and Stygian in classical-mythological register.

Tarbuttite
noun

Rare zinc-phosphate mineral first described from the Broken Hill lead-zinc deposits of Zambia in 1907, also found at Reaphook Hill in South Australia. Tarbuttite color refers to a deep-violet Broken Hill tarbuttite crystal cluster: a saturated, slightly cool deep blue-violet with the glassy finish of zinc-phosphate mineral. Named for Percy Coventry Tarbutt, an early-20th-century mining-company director.

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.

#31367b
Original
#0a417d
Protanopia
#003a7a
Deuteranopia
#014653
Tritanopia
#3a3a3a
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).
AAAon White
10.80:1
The quick brown foxSample body text at normal size. The wcag minimum for body contrast is 4.5:1 (AA) or 7:1 (AAA).
Failon Black
1.94:1

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
##31367B
Display P3
Display P3
color(display-p3 0.1958 0.2111 0.4656)
P3 has subtle headroomOKLCH chroma 0.116

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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