Having been greatly expanded from the specification in the original code, this is one of the more complicated tags, since it must cover a wide variety of colors, color qualities, shades, patterns, differences between body parts, and so on. As with the skin type tag, while you can be very specific, it might be wiser to document only the most prominent color features, at least in casual use.

While many of these are just colors, or at least can be applied to both colors and materials, some are more commonly used to refer to materials. It may be that something else about the nature of their appearance is intended to be captured, or they may work best with certain skin types (ex. silver, gold, or bronze with metal skin).

• Cag: Silver, or argent. A lustrous white, like the metal.
• Cam: Amber. The natural material varies but the typical presentation is a kind of shiny yellowish-orange, not dissimilar to honey.
• Caq: Aquamarine. Generally presented as a light teal.
• Cau: Gold, or aurum. A lustrous orange-yellow metal.
• Cbk: Black. An absence or near-absence of other color or reflection.
• Cbl: Blue.
• Cbr: Brown.
• Cbs: Brass. Usually a yellowish metal, like dull gold.
• Cbz: Bronze. The color of the material is dependent on composition and may overlap with brass, but is typically presented as being redder and/or browner than the former.
• Cch: Chromium. A steel-gray, lustrous metal, somewhat darker than silver.
• Ccu: Copper, cuprum. The pure metal is a pinkish-orange color.
• Ccy: Cyan. Between blue and green, usually a lighter shade than teal.
• Ceb: Ebony. Presumably meant to reflect the polished wood, which is shiny and black to very dark brown; there is some overlap with the darkest human skin tones and some of those are described this way.
• Cfs: Flesh, human. Presumably intended to cover the whole range of human skin tones from light pinks to very dark browns.
• Cgr: Green.
• Cgy: Grey.
• Chg: Mercury, quicksilver, hydrargyrum. The material is a reflective, silvery-white liquid. The quality of the color is similar to silver or chromium, butthere may be a differentiation by texture here.
• Cin: Indigo. Usually a dark, violet-ish blue.
• Civ: Ivory. As a color, usually described as an off-white with a faint tint of yellow.
• Cja: Jade. The material can be anywhere from white through yellow or yellowish green to a dark green; as a color it's usually thought of a somewhat unsaturated green.
• Cma (Magenta)
• Cmv (Mauve)
• Cor (Orange)
• Cpi (Pink)
• Cpu (Purple)
• Crb (Rainbow, a.k.a. violet, indigo, blue, green, yellow, orange, red)
• Cre (Red)
• Cta (Tan)
• Ctu (Turquoise)
• Cmb (Umber)
• Cvi (Violet)
• Cwh (White)
• Cye (Yellow)
• C~ (Chameleonic, able to change colour at will)
• C? (Unknown)
• C (Colourless, e.g. ice, crystal, see-through, invisible)

Most of these deal with shade, quality, and pattern.

As with the skin type tag, you can specify coloration on different parts of the body, separated by commas.