Smoldering Zenith Ruby

The progressive participle of smolder, to burn slowly without flame. Used as a color word since the late nineteenth century for the deep reds and oranges of barely-flame coal — the warm saturated darks where the heat is internal rather than emitted. Sits in the bold-and-warm corner, slightly less luminous than burning and slightly less calm than rich.

Arabic samt-al-ra's, path-overhead. As a color modifier, zenith implies an overhead-pointing-and-high-point quality, the visual register of celestial-sphere-and-overhead-Zenith hand-overhead-pointing-and-high-point celestial-sphere-and-overhead-and-Zenith-pole zenith-and-overhead-pointing-and-high-point surfaces under celestial-sphere-and-overhead-and-Zenith-pole astronomical-and-celestial-mechanics overhead-axis-light. Sits at the modifier-and-cosmic end of the grid, parallel to nadir and axis in usage.

From the Latin ruber — simply, red. The gemstone is a chromium-tinged corundum, harder than anything in nature except diamond, and so saturated that a fine Burmese pigeon's blood ruby at auction outpaces a comparable diamond by weight. The color borrows the gem's confidence: a clear, glassy red without the brown of garnet or the blue of crimson.