Regarding the Canada 2-cent Map Stamp of 1898 (Scott 85-6)
According to Unitrade, the Muddy Waters variety is mythical

Or more specifically, not a color variant, but the result of oxidation.
I know we've talked of
peroxide in other thread, so I'm asking, Will a properly-executed peroxide bath clean the 2-cent map without damaging the colors?
KirkS