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Robust Tarbuttite

#463ca4
Notes

Robust Tarbuttite (#463CA4) 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 (246°, 46%, 44%) 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 yellow. For something softer, pull in its analogous neighbors on either side of the wheel.

HEX
#463ca4
RGB
rgb(70, 60, 164)
HSL
hsl(246, 46%, 44%)
HWB
hwb(246 24% 36%)
OKLCH
oklch(43.1% 0.161 281.6)
HSV
hsv(246, 63%, 64%)
LAB
lab(32.29% 34.34 -54.96)
LCH
lch(32.29% 64.81 302.00)
CMYK
cmyk(57%, 63%, 0%, 36%)

Etymology

Robust
adjective

From the Latin robustus, of oak — implying strength combined with substance. As a color modifier, robust describes saturation combined with body: a robust burgundy, a robust olive. Sits in the bold-and-warm corner alongside strong and solid, with the slightly textural implication of a color that has substance behind the pigment.

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

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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.

#463ca4
Original
#0050a7
Protanopia
#0048a2
Deuteranopia
#14566a
Tritanopia
#464646
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
8.60:1
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
2.44:1

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