Adamant Slab Brick
Adamant Slab Brick (#A63A28) is a true red with a warm character. It leans warm, pulling light toward red, orange, and yellow. Naturally inviting, it suits editorial and hospitality contexts. Its HSL profile (9°, 61%, 40%) places it in the balanced band at a mid lightness. It works across type, buttons, and borders, saturated enough to feel deliberate but balanced enough to not fight the rest of the palette. For a confident two-color system, pair it with its complementary cyan. For something softer, pull in its analogous neighbors on either side of the wheel.
Etymology
Greek adámas, unconquerable — derived from a- (not) plus damnan (to subdue). As a color modifier, adamant implies a saturated-and-rock-hard quality where the hue maintains diamond-hard pigmentation. Sits at the bold-and-resilient end of the grid, parallel to indomitable and ironclad in usage.
Old French esclape, splinter / slab. As a color modifier, slab implies a flat-thick-stone-or-wood quality, the visual register of Cotswold-and-Yorkshire-flagstone-and-slab hand-quarried-and-flat-thick stone-and-timber-and-marble hand-quarried-flat-thick-slab surfaces under Cotswold-and-Yorkshire flagstone-and-slab quarry-light. Sits at the modifier-and-texture end of the grid, parallel to plate and tile in usage.
Fired clay, mineral red. The color refers to common building brick — iron-rich earthenware kilned to the specific dusky red-orange of a Victorian terrace, a Roman aqueduct, an adobe wall in New Mexico. Less saturated than ruby, warmer than burgundy, with a chalky cast that reads as architectural rather than decorative.
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.
Moderately saturated colors gain a small bump in P3 — the difference is usually visible side-by-side on wide-gamut hardware but won't change the character of the color.