>I just made a gum print with black + thalo blue ...(snip)
I think it would be easier if I can just use another blue that is
>less staining (yet reasonably permanent).(snip)
>
>Does anyone have any recommendation? Is ultramarine less staining?
>
>
>Dave
In my experience ultramarine is less staining, but also a weaker pigment.
Because of the problem you mention, I've gone to using a cyanotype layer as
the base coat for the blue, followed by yellow and magenta gum layers. This
solves the stain problem and gives a nice contrasty blue layer upon which the
rest of the image can be built.
Joe