Hygienic Ruff Sky

Greek hygieinós, healthful — derived from Hygieia (goddess of health). As a color modifier, hygienic implies a clear-and-medical-clean quality, the crisp color of Mid-Century-Modern clinical-and-hospital interior-architecture surfaces. Sits at the crisp-and-clean end of the grid, parallel to sanitary and sterile in usage.

Old English ruffe, Elizabethan-pleated-collar. As a color modifier, ruff implies a starched-and-Elizabethan-pleated-collar quality, the visual register of Elizabethan-and-Spanish-Habsburg-ruff hand-starched-and-Elizabethan-pleated-collar Elizabethan-and-Spanish-Habsburg-ruff-and-Holbein-portrait ruff-and-starched-and-Elizabethan-pleated-collar surfaces under Elizabethan-and-Spanish-Habsburg-ruff-and-Holbein-portrait Tudor-and-Spanish-Habsburg-court starched-collar-light. Sits at the modifier-and-textile end of the grid, parallel to gown and frock in usage.

The blue of a clear sky at noon — produced by Rayleigh scattering, the preferential dispersion of shorter wavelengths through atmospheric molecules. Air itself is colorless; the color we see is sunlight scattered toward our eyes by every cubic kilometer above. The reference shade is mid-latitude noon under a high pressure system: a clean, slightly green-shifted blue with the luminous depth of light scattered across an entire hemisphere of air.