> is there anything to "worry about" if I don't remove
> the dichromate by extended washing?
Possibly. It's a strong oxidising agent, and as Peter Marshall remarks,
could react with *some* pigments (generalizations not possible here -
depends on pigment). It could also slowly oxidise the cellulose or sizing
agent, which wouldn't improve paper strength.
> What, if any, are the
> long-term effects of either chromium (VI) or chromium (III) on
> a gum print?
It's worth bearing in mind that *every* gum or carbon print must contain
chromium(III) - especially in the high density areas - because it is the
chromium(III) ions that form the cross-links between the colloid molecules,
rendering them insoluble.
> Is one more stable/less damaging than the other?
Dichromate could be more damaging, and, since you can't avoid the presence
of chromium(III) anyway, I guess it makes sense to use the (meta)bisulphite
bath. Use both belt and braces.
Mike