Phosphorescent Emerald
Phosphorescent Emerald (#81D97C) is a true green with a cool character. It leans cool, sitting on the blue, green, and violet side of the wheel. Quiet and dependable, a fit for product UI and data visualization. Its HSL profile (117°, 55%, 67%) 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 violet. For something softer, pull in its analogous neighbors on either side of the wheel.
Etymology
Greek phōsphóros, light-bringer — adjectival suffix -escent. As a color modifier, phosphorescent implies a saturated-and-cool-glow-after-stimulation quality, the bright cool-green-blue color of Cu-doped-ZnS glow-in-the-dark photoluminescent surfaces. Sits at the bright-and-cool end of the grid, parallel to fluorescent and luminous in usage.
A chromium-tinged variety of beryl — the gemstone mined from the Cleopatra-era Mons Smaragdus in Egypt, the Muzo deposits of Colombia, and the Sandawana mines of Zimbabwe. Emerald green refers to a high-clarity faceted emerald with strong color saturation: a saturated, slightly blue-shifted green with the gem's signature internal life. Cooler than fern, warmer than teal, with the heraldic weight of two thousand years of royal favor.
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.