I want to use Argentium Sterling Silver for Keum-boo projects but
there is nothing in the otherwise great Rio Grande article that
addresses this issue. I know that I must anneal at a lower
temperature. How many times should I anneal to bring the silver to
the surface? What coloring should I expect as I go through the
multiple annealing process?
I hope someone can help me
Anne Cunningham
Hi Anne,
When I do Kum Boo on Argentium Silver, I anneal and pickle the
silver clean at least once. Once is generally enough.
To me, a slightly textured surface holds the foil better than a
smooth surface, but a friend who does a lot of Kum Boo on AS says
that she does not notice a difference.
If the Kum Boo is the last step, then you can use the thin foils
that are commercially available. If, however, you wish to be able to
solder afterwards, use the thicker foil that Allcraft carries, or
roll your own foil. AS seems to “fade” the gold even more quickly
when heated than SS.
I find that scrubbing the surface with baking soda after pickling
and rinsing gives me much better adhesion. I’m not sure whether it is
the fact that it is neutralizing any pickle left in the pores of the
metal, or that the mild abrasive quality it has is making the surface
slightly rougher. What I do know is that it works better when I do
scrub with baking soda prior to applying the foil.
In summary, the primary differences are:
-fewer heating and pickling repetitions are needed for AS
-If AS with Kum Boo is soldered on, thin gold foils REALLY fade.
I hope this is helpful!
Cynthia Eid
I want to use Argentium Sterling Silver for Keum-boo projects but there is nothing in the otherwise great Rio Grande article that addresses this issue. I know that I must anneal at a lower temperature. How many times should I anneal to bring the silver to the surface? What coloring should I expect as I go through the multiple annealing process?
People have mentioned depleting Argentium on Orchid before. However,
I was recently trying to get some advice from the Technical
Department of the Worshipful Company of Goldsmiths. The officer
there, a metallurgist, wrote that what happens in depletion is that
the surface copper oxides (in sterling) get dissolved by the pickle,
leaving a fine silver surface after several treatments.
He suggested that with Argentium, it was probable that the remaining
germanium would “sit” on the surface, as the germanium does not
dissolve in pickle. He also said that germanium is soluble in
hydofluoric acid - and no I would not have that in my studio, before
people get cross!!!
However, matting salts for glass are some sort of hydrofluoric
salts, and I wonder whether this would do the job, albeit slowly?
Matting salts are used in schools and colleges and seem to be much
safer to use.
Has anyone tried this?
Tamizan
I’ve only done it a few times, but in my experience you don’t need
to depletion gild Argentium to apply Keum Boo foil. It just needs to
be nice and clean, and, in my hands at least, a little bit warmer
than a similar thickness of fine silver needs to be.
I specifically used it because I’m lazy, and didn’t want to spend
the time to depletion gild the peices, and it worked well once I got
it hot enough.
Jason