Luminous Tarbuttite
Luminous Tarbuttite (#9A72F7) is a soft indigo 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 (258°, 89%, 71%) places it in the highly saturated band at a light 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 lime. For something softer, pull in its analogous neighbors on either side of the wheel.
Etymology
Latin lūminōsus, full of light — adjectival suffix -ous, derived from lūmen (light). As a color modifier, luminous implies a saturated-and-light-emitting quality where the hue carries internal-glow visual register. Sits at the bright-and-saturated end of the grid, parallel to radiant and resplendent in usage.
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 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.