Simple Touchstone
Simple Touchstone (#515258) is a deep neutral with a mono character. It's a grayscale value, at home in typography, dividers, and the structural layer beneath stronger colors. Its HSL profile (231°, 4%, 33%) places it in the muted band at a dark lightness. It works as a background, hairline border, or text color in dark UI. Swap to true black when you need maximum contrast. Pair it with almost any saturated accent. It's built to sit underneath or behind stronger colors without fighting them.
Etymology
Latin simplus, single — sharing root with English single and simplex. As a color modifier, simple implies a neutral-and-uncomplicated-and-stripped-down quality where the hue carries the visual register of Shaker-and-Quaker-craft uncomplicated-and-honest hand-built-craft surface-finish. Sits at the neutral-and-stripped-down end of the grid, parallel to unassuming and modest in usage.
Old English tāc-stān, test-stone — the cool-mid-gray fine-grained Jasper-and-Lydite metamorphic-rock used in Bronze-Age-and-medieval European gold-and-silver-purity testing-and-assaying. Touchstone color refers to a freshly polished Lydite touchstone face with multi-decade gold-streak-test residues in raking light: a balanced cool gray with the matte finish of fine-grained metamorphic-rock with multiple gold-and-silver streak-test traces.
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
This color has effectively no chroma (OKLCH C = 0.010) — it’s on the grayscale axis. Hue rotations don’t change a grayscale color, so complementary, analogous, triadic, and split-complementary all reduce to the same value. They aren’t shown because four identical tiles would be misleading.
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.