Open Sour Verdigris

Old English open, unobstructed — used as a color modifier since the eighteenth century for hues that read as airy or uncrowded. Open blue, open green: moderate saturation combined with optical spaciousness, the slight visual breath of a hue that doesn't crowd the surface it covers. Sits at the crisp-bucket center alongside clear.

Old English sūr, acid-or-fermented. As a color modifier, sour implies a fermented-and-puckered-and-acid quality, the visual register of sourdough-and-Bavarian-sauerkraut-sour hand-fermented-and-puckered-and-acid sourdough-and-Bavarian-sauerkraut-sour-and-Belgian-Lambic sour-and-fermented-and-puckered surfaces under sourdough-and-Bavarian-sauerkraut-sour-and-Belgian-Lambic San-Francisco-sourdough-and-Brussels-Lambic fermented-puckered-light. Sits at the modifier-and-flavor end of the grid, parallel to tart and tang in usage.

The basic copper carbonate that forms on weathered copper and bronze — the pigment scraped from oxidized metal and used in Renaissance painting before being supplanted by more stable greens. The color refers to a thick verdigris on aged copper roofing or the Statue of Liberty's surface: a soft, slightly muted blue-green with the powdery finish of mineral oxide. Cooler than patina, warmer than seafoam, with the archaeological weight of a mineral made by time.