Could someone please elaborate the Pottassium
Nitrate/Alum/Salt method. Am I correct when I understand that it
is a surface depletion process?.
In 1989/90 I did an extensive research project compiling lists of
different approaches to depletion gilding, which is published here
at the Ganoksin project:
This is one of the many approaches that goldsmiths have used to
enrich the surface (and even refine) gold alloys. Varying mixtures
of these three chemicals are widespread worldwide among goldsmiths
for this purpose.