Certain Celtic Mulberry

Latin certus, fixed / sure — sharing root with English concern and certify. As a color modifier, certain implies a saturated-and-unambiguous quality where the hue declares its character without hesitation. Sits at the bold-and-confident end of the grid, parallel to assured and decisive in usage.

Latin Celticus, of-the-Celts. As a color modifier, celtic implies a knotwork-and-La-Tène quality, the visual register of Irish-and-Welsh-and-Scottish Celtic-knotwork hand-carved bronze-and-stone metalwork-and-illuminated-manuscript surfaces under Celtic-Irish-Welsh-Scottish illuminated-manuscript-tradition light. Sits at the modifier-and-cultural end of the grid, parallel to norse and welsh in usage.

The genus Morus — the white mulberry (M. alba) feeds silkworms; the black mulberry (M. nigra) bears the deep purple fruit that stains everything it touches. The color refers to a ripe black mulberry: a saturated, slightly red-shifted very deep purple with the slight juiciness of a compound fruit. Cooler than wine, warmer than indigo, with the agricultural weight of a tree that supported the entire Chinese silk industry for two thousand years.