From what I can glean Holly (not that I have been reading up on showing roans for any reason you understand
) minks come under non-standard and any sub-groups of mink (i.e. mink banded, mink roan etc.) would therefore come under this category too.
As far as I can see (in my limited experience admitedly) the easiest way to remember it is the animal goes in the highest class number that applies to it.....non-standard colour is class 20 and the highest at the show so that would be the class!
Maybe someone with more experience could let me know whether I am right?