Suggestions for blackening solution for gold plated jewelry? I
normally use Win-Ox or similar products on solid gold & silver,
but I'm not happy with the results on plated pieces. Would
appreciate input on this, thanks!
Your problem may be due to the nature of much gold plating. Although
the solutions are sold with labels suggesting various karats, for the
most part, that indicates an approximate color, not the actual karat
of the plated deposit. Most gold plating solutions sold to jewelers
(the typical quart size bottles) actually plate a deposit that is not
too far from pure gold, even when the label suggests a lower karat.
That high gold content of the plated layer would make it quite
difficult to get decent black color via any sort of chemical
oxidation/etc such as with Win-Ox or the like, which usually react
with the base metals in an alloy, not the gold itself. If the plating
is thin enough, then perhaps the solutions will react with the metal
under the plated layer, but this gets iffy.
Better would be to abrade through the plated areas where you wish it
to be blackened, or alternatively, mask off those areas when you
plate, so they don’t get plated. Then your solutions will have
something they can react with.
Alternatively, get your black color with a subsequent black plated
layer, such as black nickel or black rhodium. Done with a pen plater,
you can do it just where you wish, or with black nickel in
particular, (not so much with the more durable black rhodium) you can
abrade the black back off again on high spots, just as with
conventional chemical blackenings.