Acid Pile Peridot

Latin acidus, sour — sharing root with English acrid and acerbic. As a color modifier, acid implies a saturated-and-citric-and-zingy quality, the bright color of lemon-and-lime citrus-fruit-flesh and acid-yellow fluorescent-pigment surfaces. Sits at the bright-and-cool end of the grid, parallel to acidic and electric in usage.

Old French pile, raised-cut-thread. As a color modifier, pile implies a raised-cut-thread-and-velvet quality, the visual register of velvet-and-corduroy-and-pile-rug hand-cut-and-raised-thread velvet-and-corduroy-and-pile-rug-textile surfaces under velvet-and-corduroy-and-pile-rug textile workshop-light. Sits at the modifier-and-texture end of the grid, parallel to plush and nap 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.