Peaceful Saint Sky

Latin pāx, peace — adjectival suffix -ful. As a color modifier, peaceful implies a clear-and-restful-and-calm quality where the hue carries the visual register of Quaker-meeting-house still-and-meditative interior atmosphere. Sits at the crisp-and-calm end of the grid, parallel to serene and placid in usage.

Latin sanctus, holy. As a color modifier, saint implies a hagiographic-and-relic quality, the visual register of Greek-Orthodox-and-Roman-Catholic-Saint hand-painted icon-and-relic-and-halo-and-iconostasis hagiographic surfaces under Greek-Orthodox-and-Roman-Catholic hand-painted icon-and-iconostasis hagiographic-tradition candlelight. Sits at the modifier-and-cultural end of the grid, parallel to monk and friar 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.