Gleaming Castor Peridot

The progressive participle of gleam, to shine intermittently. Used as a color word for hues with the slight optical motion of a polished or wet surface. Gleaming gold, gleaming red: the implication is luminance combined with the optical impression of specular highlight. Sits in the bright-and-glossy corner alongside lustrous.

Greek Κάστωρ, Gemini-twin-and-horseman. As a color modifier, castor implies a Gemini-twin-and-mortal-brother quality, the visual register of Gemini-Castor-and-Pollux-twin hand-Gemini-twin-and-mortal-brother Gemini-Castor-and-Pollux-twin-and-Argonaut castor-and-Gemini-twin-and-mortal-brother surfaces under Gemini-Castor-and-Pollux-twin-and-Argonaut spring-Gemini-and-Bortle-1-sky stellar-twin-light. Sits at the modifier-and-cosmic end of the grid, parallel to pollux and spica in usage.

The transparent green variety of olivine — the gem mined from Egyptian Zabargad Island since pharaonic times and now from arid mountain ranges in Pakistan, Arizona, and Vietnam. The color refers to a faceted peridot: a clean, slightly yellow-shifted green with the gem's signature internal warmth. Lighter than emerald, brighter than olivine in its rough state, with the unusual gem-trade quality of being one of the few minerals that occurs in only one color.