Heavy Sloop 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.

Dutch sloep, single-masted-vessel. As a color modifier, sloop implies a single-masted-fore-and-aft-rigged-vessel quality, the visual register of American-and-Dutch-sloop hand-built single-masted-fore-and-aft-rigged sloop-and-cutter maritime-architecture surfaces under American-and-Dutch sloop-and-cutter maritime sailing light. Sits at the modifier-and-nautical end of the grid, parallel to skiff and hull 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.