Properly Maelstrom
Properly Maelstrom (#04152A) is a deep azure 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 (213°, 83%, 9%) 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 orange. For something softer, pull in its analogous neighbors on either side of the wheel.
Etymology
Latin proprius, one's own — adverbial-and-adjectival suffix -ly. As a color modifier, properly implies a neutral-and-appropriate-and-correct quality where the hue carries the visual register of conventionally-fitting-and-correct color-decision matched to its functional context. Sits at the neutral-and-traditional end of the grid, parallel to appropriately and suitably in usage.
Norwegian Malstrøm, grinding-stream — the deep-cool-gray Saltstraumen tidal whirlpool off Norway's Bodø coast, the strongest tidal current in the world. Maelstrom color refers to a Saltstraumen whirlpool surface at peak tidal flow: a dark cool-gray with the optical complexity of high-velocity tidal-current-mixed Norwegian-coast saltwater against the deep Salten-fjord marine-stratified water column.
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.
Wide gamut
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.
This color sits well within the sRGB cube. P3 and sRGB share the gray axis and most desaturated tones, so a P3 display renders this identically to an sRGB display.