Deep Cordierite
Deep Cordierite (#423470) is a deep indigo 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 (254°, 37%, 32%) 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.
Etymology
Old English dēop, profound, far down — sharing root with dive and dipper. In color shorthand, deep implies low lightness combined with high saturation: a deep red is darker than crimson but no less chromatic. Where dark describes value alone, deep implies that the hue still has presence at that low light level. Closer to rich than to somber.
Silicate mineral marketed as the gemstone iolite — pleochroic deep-blue-violet from one viewing angle and pale-yellow from another. The Vikings reportedly used thin slices as polarizing filters to locate the sun through cloud (sólarsteinn). Cordierite color refers to a cleaved Norwegian cordierite cabochon viewed along the deep-blue axis: a saturated, slightly cool deep blue-violet with the glassy finish of pleochroic gem silicate.
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.