Durable black or dark antique on 18K gold?

Jewelry Discussion
1

We’re looking for a means to achieve a durable black or dark antique
finish in recessed areas of some of our pieces. In silver or lower
karats of gold, liver of sulphur (silver) or the more aggressive
gold/silver oxidizer solutions do a decent job, though durability
isn’t always great. We’ve played with black rhodium plating with
variable results, and black nickel, with even poorer results. we
don’t want to use the paint on colors. It seems to us that the class
ring companies seem to have figured this out, at least for the lower
karats, as their finishes seem able to withstand quite a bit, even
heating them up or pickling the rings. Does anyone happen to know
what they’re using for antiquing? Calls to Jostens to ask got a
response of “can’t give out that info”. Part of the problem is just
that much of the metal we’re trying to antique is 18K white gold,
which of course it not exactly an easy metal to get a dark oxide
finish on… I’m guessing some sort of plating or other electrolytic
bath, but it’s got to be a reasonably durable finish that will resist
at least a bit of scratching. Any specific suggestions of types or
sources would be appreciated. Please copy replies to my email as
well. thanks.

Peter Rowe
(for Sholdt jewelers)

2

Peter-- You might try tincture of iodine I know it works on yellow
havent tryed on white.

Don in Idaho

3

Peter,

I’ve never had the opportunity to try this but I think it has a
pretty good chance of working. If you silver-plate a white gold ring
and then color it with LOS not only could you achieve a decent dark
color, but as long as the silver was recessed it’d eventually attain
a natural patina that would probably be even tougher than the
original. On high karat yellow gold I’d try a copper plate followed
by LOS.

Larry Seiger

4

Hi Peter;

One of the toughest black finishes I’ve ever gotten was one done by
heating nickel bearing stainless steel alloys. It’s not real dark,
but a fairly dark gray color, very even too. My thinking is that it
was that famous passive nickel oxide we all have had so much trouble
with. I’m just suggesting, since nickel plating is a tough coating,
maybe a heavy nickel plate which is subsequently oxidized with heat
would be worth looking into.

David L. Huffman