Buttoned Sulfur
Buttoned Sulfur (#566909) is a deep yellow 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 (72°, 84%, 22%) 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 indigo. For something softer, pull in its analogous neighbors on either side of the wheel.
Etymology
Old French bouton, button — past-participle of button. As a color modifier, buttoned implies a clear-and-fastened-and-formal quality, the crisp color of Edwardian-period formal-attire fully-fastened-and-formally-dressed gentleman's-attire. Sits at the crisp-and-finished end of the grid, parallel to trim and pressed in usage.
Element S, atomic number 16 — bright yellow crystalline mineral around volcanic vents from Sicily to Hokkaidō. Pure sulfur dust gave its color to the explosive mixtures of medieval gunpowder and to the fungicide vineyards of nineteenth-century France. The color is the surface of a freshly cleaved sulfur crystal: a saturated, slightly green-shifted yellow with the resinous finish of the elemental mineral.
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.