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Foreboding Cassis

#640891
Notes

Foreboding Cassis (#640891) is a deep violet with a jewel character. It carries the deep, saturated richness of a gemstone. Authoritative and slightly formal, it works well for type and heavy UI elements. Its HSL profile (280°, 90%, 30%) places it in the highly saturated band at a dark 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 green. For something softer, pull in its analogous neighbors on either side of the wheel.

HEX
#640891
RGB
rgb(100, 8, 145)
HSL
hsl(280, 90%, 30%)
HWB
hwb(280 3% 43%)
OKLCH
oklch(39.3% 0.193 309.2)
P3
color(display-p3 0.3579 0.0751 0.5470)
HSV
hsv(280, 94%, 57%)
LAB
lab(26.53% 56.24 -52.61)
LCH
lch(26.53% 77.01 316.91)
CMYK
cmyk(31%, 94%, 0%, 43%)

Etymology

Foreboding
adjective

Old English fore-bēodan, to announce in advance — present-participle of forebode. As a color modifier, foreboding implies a deep-and-threatening atmospheric-anticipation quality, the dark cool-gray of advancing-cyclone storm-front cumulonimbus-base. Sits at the deep-and-threatening end of the grid, parallel to ominous and menacing in atmospheric tone.

Cassis
noun

French for blackcurrant (Ribes nigrum) — the deep-violet drupe used in Burgundian Crème de Cassis liqueur and Kir aperitif. Cassis color refers to a freshly macerated Ribes nigrum drupe-pulp in a Burgundian Crème de Cassis base: a saturated, slightly cool deep violet with the matte finish of anthocyanin-rich blackcurrant juice. Slightly warmer than Cabernet-style table wine.

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.

#640891
Original
#003c94
Protanopia
#00408f
Deuteranopia
#5d3454
Tritanopia
#252525
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
10.58:1
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
1.99:1

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
##640891
Display P3
Display P3
color(display-p3 0.3579 0.0751 0.5470)
P3 has visible headroomOKLCH chroma 0.193

This color is chromatic enough that authoring it as P3 native (instead of clamping to sRGB) gives a perceptibly more saturated render on wide-gamut displays — modern Macs, iPhones, iPads, and most recent OLED laptops.

Related Colors

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