... you would first start with Black, then White, Green, Red, and finish on smooth veg leather.
Please note that this order of colors is not universally valid.
As Komitadjie wrote already in post #2 in this very thread
There are a LOT of compounds, and they're all different.
Every maker has a different formulation, and one maker's "black"
compound is going to be very different from another's.
Two examples: if your compounds were of the Neroli brand,
you would use the colors in this order: Yellow, Green, Grey, Red, Blue, and White.
If you fancy the Luxor brand, the order would be Red, Green, Grey, Blue, Yellow, White, and Orange.
Great fun, eh?
To make things even worse, just because a certain compound is green,
you can't be sure that it contains CrOx. And if it should happen to contain
CrOx, you cannot be certain that it is of the 0.5 Micron variety (ref. Brent Beach).
Unfortunately, most manufacturers consider the contents a trade secret.
In Germany, they just publish relative values of Cut and Gloss on a scale
from 1 to 10. I have found one manufacturer (in France) that publishes
grit size (seven compounds from 6.5 Micron down to 0.1 Micron).
Hopefully, others might do the same in the future.
Have fun!
Claes