#555B59Crucible (#555B59) is a grey neutral with an OKLCH hue of 174°, lightness 0.47 and chroma 0.008. In practice it behaves as a mid-weight working color for secondary surfaces and editorial blocks.
| HEX | #555B59 |
|---|---|
| RGB | rgb(85, 91, 89) |
| HSL | hsl(160, 3%, 35%) |
| HSV | hsv(160, 7%, 36%) |
| CMYK | cmyk(7%, 0%, 2%, 64%) |
| CIE Lab | lab(38.1 -2.8 0.3) |
| OKLCH | oklch(0.465 0.008 174) |
Under warm 2700K interior light Crucible shifts only faintly, with no single dominant change; in north-facing or shaded light it is virtually unchanged. Overall drift across common illuminants is small (max ΔE ≈ 1), so it is a lighting-stable choice.
#595953 — ΔE 1.0, shifts only faintly, with no single dominant change#595b57 — ΔE 0.7, is virtually unchanged#555b59 — ΔE 0.0, is virtually unchanged#555b5a — ΔE 0.2, is virtually unchangedTest Crucible in the color lighting simulator — sweep it through daylight, warm 2700K light, 4000K LED, and shade alongside the rest of your palette.
Against white it measures 6.94:1 and against black 3.03:1, so white text is the stronger pairing. That pairing passes WCAG AA for body text.
One color explored: close hues with real lightness and chroma structure, so the palette is the anchor through value rather than a set of colors.
#a9aeac · #828886 · #555b59 · #3d4240 · #1e2321 · #050706
The anchor's neighbours on the wheel — everything shares an undertone, so the chord carries color without anything having to be muted to get along.
#50868d · #367773 · #555b59 · #23543a · #254222 · #232f0c
The mid-gap pairing — sage and mustard, terracotta and olive. A foil rotated 40–65° toward warm or cool: too far to be kin, too near to argue, carried by temperature and a deliberate value offset.
#98b9c7 · #5f9eb7 · #5f7b87 · #555b59 · #0c493c · #002d23
One deliberately opposed voice — a single restrained counterpoint across the wheel, or temperature against temperature where the anchor is too muted to carry a loud opposite.
#a4c5ba · #b57d93 · #555b59 · #30403b · #05271f · #000b07
The anchor as the only color in the room. True neutrals or complement-warmed near-neutrals let it stay dominant.
#f8eff2 · #a7b4af · #777173 · #555b59 · #384440 · #020101
This color as a ground rather than a subject — its own restraint held across a narrow value band, carrying one saturated voice from the opposite temperature.
#f0f2f1 · #cacdcc · #555b59 · #2d3130 · #0c100f · #e55198
The same quiet ground carrying one bright gold voice — the high-energy pairing a cool or muted anchor cannot reach through its own temperature.
#f0f2f1 · #cacdcc · #555b59 · #2d3130 · #0c100f · #f1ba4d
The opposite hue on the perceptual wheel, tempered to field strength — warm/cool tension without vibration.
#ffecf3 · #d0a1b3 · #966076 · #555b59 · #5b3243 · #000201
The complement's two neighbours instead of the complement itself — strong contrast with a lower clash risk.
#ffecf3 · #c4a4c6 · #9a615d · #555b59 · #523554 · #050000
Three hues spaced evenly around the wheel; the anchor leads and the other two are held at supporting strength.
#f2efff · #b2aad3 · #966748 · #555b59 · #5b371e · #010006
Two complementary pairs offset by 90° — the richest chord, kept usable by a strict lightness hierarchy.
#ebf2ff · #9db1d7 · #966076 · #555b59 · #513e14 · #040001
#717675 · #8e9290 · #aaadac · #c6c8c8 · #e3e4e3
#474c4a · #393d3b · #2b2e2d · #1c1e1e · #0e0f0f
Its moderate chroma lets it work in mid-size areas — upholstery, secondary UI surfaces, editorial blocks — without overwhelming neighbors.