Heavy Hoar Tanzanite

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.

Old English hār, grey-with-age-or-hoar-frost. As a color modifier, hoar implies a grey-aged-and-hoar-frosted quality, the visual register of English-meadow-and-hedgerow-hoar hand-grey-aged-and-hoar-frosted English-meadow-and-hedgerow-hoar-and-frosted-pasture hoar-and-grey-aged-and-hoar-frosted surfaces under English-meadow-and-hedgerow-hoar-and-frosted-pasture Cotswold-and-Yorkshire-Dales-frost-pasture frosted-meadow-light. Sits at the modifier-and-weather end of the grid, parallel to rime and sleet in usage.

A blue-violet variety of zoisite — discovered in 1967 in a single small area of northern Tanzania near Mount Kilimanjaro and marketed by Tiffany & Co. shortly after. The color refers to a faceted tanzanite cut to maximize its strong pleochroism: a saturated, slightly violet-shifted deep blue-purple with the gem's signature internal life. Cooler than amethyst, warmer than iolite, with the gem-trade specificity of a stone that occurs in exactly one place on Earth.