Spectral Terra Malachite

Latin spectrum, appearance — adjectival suffix -al. As a color modifier, spectral implies a saturated-and-rainbow-decomposed-and-pure quality, the bright color of Newton-prism sunlight-decomposed seven-color spectrum band. Sits at the bright-and-pure end of the grid, parallel to prismatic and pure in usage.

Latin terra, earth-or-land. As a color modifier, terra implies a earth-globe-and-loamy-and-grounded quality, the visual register of Pale-Blue-Dot-and-Apollo-Terra hand-earth-globe-and-loamy-and-grounded Pale-Blue-Dot-and-Apollo-and-Earthrise terra-and-earth-globe-and-loamy-and-grounded surfaces under Pale-Blue-Dot-and-Apollo-and-Earthrise lunar-orbit-and-deep-space earth-globe-light. Sits at the modifier-and-cosmic end of the grid, parallel to luna and sol in usage.

A copper carbonate mineral — Cu₂CO₃(OH)₂ — that crystallizes as concentric green bands in oxidized copper deposits. Mined for ornamental stone since ancient Egypt, ground into pigment for medieval European painting, polished into the malachite columns of the Russian Hermitage. The color refers to a polished cabochon: a saturated, slightly muted green with the high shine of stone and the visible banding of growth rings.