Dumb question about Van dyke toning

All:

I'm reentering the exciting world of post-factory photography this
month, and had a question about van dyke toning.

If I understand it correctly, one tones the print after rinsing in an
acidic (?) water bath, then uses an acidic bath with a noble metal for
a number of minutes, then fixes the print and rinses it.

Why the fixing step? If palladium platinum or gold have replaced the
silver, is there a need to fix the print? Has anyone done tests on
this?

Thank you

Gordon Cooper
Received on Sun Apr 3 12:48:21 2005