How to get a white Silver finish?

[Paul WIlson]

Folks,
I noticed that silver castings are, well, white...right after casting.
One does then polish them to make them shiny like silver.

How might I turn a polished piece back to the white state?

I have some cast seashells that need that white finish.

Thanks,
Paul Wilson
eliasbing.com

[Todd Rich]

> Thanks,
> Paul Wilson
> eliasbing.com

I get that look with the silver if I heat it up to about 1300F-1500F
without coating it with a flux first. I believe the white is silver
oxide.

[Carl 1 Lucky Texan]

Have you tried bead/sandblasting? Might be close enough to the finish
you're after.
Or I suppose you could invest and reheat the item to casting temp. Just
remove the investment? Seems like you would still have oxides to deal
with though.

You said silver - is it sterling or unalloyed?

Carl

--
to reply, change ( .not) to ( .net)

[Ted Frater]

Your very lucky to not get oxide forming at that temperature, that
could be because your heating in an inert atmosphere or a reducing one
or your using fine silver.Thats 999/1000 to those that dont know.
Heating sterling grade thats 7.5% copper/silver without flux in an
ordinary flame will turn it black in no time.
so unless you know what your doing,
dont.
Or run a replicapable trial on some scrap first, before putting the
real item in the fire.
To get rid of the black youll need to dissolve the copper oxide out of
the silver. For that youll need a reactive flux with flurides in it.
there designed for a quite different aplication so wont be available
from your normal jewellers supply house.
they will do the job but theres a health risk in their use.
A touch of the sorcerer's apprentice here I think.
Do your research first, then run trials to get the technique right then
do the proper job.
that way your less likely to screw up.

[Sarit Wolfus]

You could brush polish the piece using a fine brush to regain the
white look. There are fine glass, pencil-like brushes in the market
that make a great job.
Or, as in reticulated silver, you could evenly heat the piece to turn
it black and then pickle to remove the copper oxide layer and leave a
thin white fine silver layer. Repeat the process until you are happy
with the result.
Sarit.
http://sarit-jewelry.com