OK so I made a troll color spectrum chart for myself, and I figured I might as well post it up for others to enjoy. The only canon elements to that, are the colors for horns, and the colors for the original hemospectrum, plus karkat.
The brightened colors were done by taking the original color, and pushing the hue up to the correct intensity. I noticed Karkat’s blood color is just a more intense version of Aradia’s. Thus those are probably rather reliable.
I did skin by trying to replicate a similar value as the neutral grey, but moving it over so it would take on some tone. (Note, the borders are all troll neutral grey.)
Hair color is a head canon that troll hair is not black, but highly concentrated blood color pigment.
So feel free to use this chart if you wish, just remember that the only true canon colors are the ones mentioned previously. Have fun.
PS. We just were having fun by naming the bright colors XD