Question for anyone has attempted it:
Have you tried to replicate an iridescent surface while painting? If so, how did you do it? Was it a large scale color shift, or more subtle? I was thinking of a possible green-blue-purple sort of thing, shading a surface with one color set... depending on how folded the surface is.
Currently this is all just me theory-crafting, but I am curious if it can be and has been done. Knowledge questing!