Heavy Void Sapphire

Old English hefig, weighty — cognate with heave. Used as a color modifier since at least the seventeenth century to indicate weight in saturation as much as value: heavy with pigment, heavy-bodied. In the engine's adjective grid, heavy sits alongside deep and plush in the dark-and-saturated quadrant. Closer to a fabric description than a pure value word.

Latin vocivus, empty-or-vacant. As a color modifier, void implies an empty-and-vacant-and-bottomless quality, the visual register of Yves-Klein-and-Rothko-void hand-empty-and-vacant-and-bottomless Yves-Klein-and-Rothko-and-Malevich-Black-Square voided-and-empty-and-vacant-and-bottomless surfaces under Yves-Klein-and-Rothko-and-Malevich-Black-Square monochrome-canvas-and-color-field-and-suprematist gallery-and-void-light. Sits at the modifier-and-mood end of the grid, parallel to blank and hollow in usage.

An iron-and-titanium-bearing corundum — the same mineral as ruby, hardness 9 on the Mohs scale, mined for two millennia from Sri Lanka, Burma, Madagascar, and the Cashmere mines of British India. The color refers to a fine Kashmir-cut sapphire: a saturated, slightly violet-shifted deep blue with the gem's signature internal velvet — a quality of light scattering in the stone that faceted glass cannot replicate. Cooler than cobalt, deeper than azure.