Exotic Colors of Carcosa:
* Dolm: A compound color of ulfire and blue." - A Voyage to Arcturus (1920) by David Lindsay.
* Jale: A primary color, is described as: "dreamlike, feverish, and voluptuous." - A Voyage to Arcturus (1920) by David Lindsay.
* Ulfire: A primary color, is described as: "Just as blue is delicate and mysterious, yellow clear and unsubtle, and red sanguine and passionate, so he felt ulfire to be wild and painful." - A Voyage to Arcturus (1920) by David Lindsay.
* Skelus: The actual color of Bone Men skin/flesh. Other races see it as transparent, though they can see themselves. (See Bone Men description.) Some other creatures on Carcosa that are transparent are also of the "Skelus" spectrum. Others are just simply transparent. The technology of the Space Aliens can interpret with specialized scanners, though Bone Men who have observed these scans find the image highly lacking, much like an Earth human comparing a Color HD TV image to an old analog black and white television. You get the rough idea but miss out on so much more.
* Soruse: The color spectrum of raw Sorcery. Only naturally seen by Jale Men, though rare individuals or high level Sorcerers can gain sight into this spectrum.
This could probably be comparable to Octarine – the color of magic in the Discworld fantasy novels.