I have been messing around with pens, but they sort of cover the
underlying image and are in no way transparant. I have tried Palegold
(Schmincke), which is a sort of paste to be mixed with e.g. linseed oil,
but it doesn't really mix with the emulsion; it tends to stay on top of
the emulsion and doesn't really show, unless you move your paper, so
that the light will hit the gold and it will reflect. Using pigments
might be possible, but how (with what) are they to be mixed in order to
blend into the emulsion of my photographic paper? Maybe there is after
all a sort of toner, which will produce (real) gold.
Jacques Verschuren