Silver turns grey in pickle

Hi All- I’ve searched the archives - I’m sure the answers must be
there, but perhaps I didn’t type in the correct subject line. So:
Sometimes my sterling turns grey in the pickle. It’s not firescale -
unfortunately I know what that is. I don’t think it’s the pickle
because I can fix the problem by fluxing the piece entirely, heating
& pickling again - comes out great. But I still wonder what causes
it & how to prevent it from happening. Thanking you all in advance
for your advice.

Sheila

I have absolutely had this happen to me and I have never been able to
figure out why. I’ve brought a piece of the affected silver to
meetings and workshops–still no answer. Look forward to someone
knowing the answer!!

Thanks in advance.
Carolyn

I’m getting convinced it’s something in the glaze in the slow cooker
liner- I too have had it happen to both sterling and fine silver and
there is no other explaination other than contamination inadvertently
by the steam from the acid condensing on the metal rim of the cover
to the slow cooker and dripping back into the pickle…The rims are
base metals and will therefore contaminate acid baths/pickle in a
flash…Of course you are not pickling gold filled material in the
same pot as other metals right! - in fact pickling GF material
without plating the ends will ruin a batch of pickle. as will iron
containing waters (sulphur scented water,or rotten egg smelling
waters) and salts that may collect on the rim of the liner from using
tap water out of galvanized pipes…rer

Whatever you are using for pickle seems to be reacting with the
silver (or the copper in it if Sterling). Of course your pickle could
also be contaminated causing the reaction.

John
John Atwell Rasmussen, Ph.D., AJP
http://www.rasmussengems.com
http://rasmussengems.ganoksin.com/blogs/

I think that you have either pickled it too long or in too strong a
solution. The surface is etched and will need light sanding and
buffing.

marilyn

Hi Carolyn,

you have probably left the silver in the pickle for to long. Also if
the acid gets to saturated with copper this can be a cause. Don’t
allow you acid to go at all green.

Richard

I’ve seen this happen in class when a student burnishes the silver
with a brass brush forgetting to use it with soapy water. My guess
is that a nearly invisible layer of brass is deposited on the silver
and this is what is causing the silver to turn gray when it is
subsequently heated and pickled. Just a guess from an
observation… I am definitely not a metallurgist.

Carol Holaday

pickling GF material without plating the ends will ruin a batch of
pickle. 

I don’t see how this can be… The GF I am familiar with is gold over
brass, and pickling brass doesn’t ruin pickle as far as I ever heard.
Plus it would take a LOT of ends of wires, etc, to ruin pickle even
if they were iron!

Noel

Is Tarnex a pickle solution? A friend of mine left her sterling
silver in it overnight. It turned a matte grey-white. I put it in
the tumbler for a couple of hours and it’s back to bright and shiny
but I was wondering if Tarnex is the same as the pickling solution I
use?

Michele
MikiCat Designs

Here’s what I don’t understand: if the pickle were contaminated, why
will the piece clean up after I flux & heat & pickle again - in the
same solution. This has happened with sterling & I think it might
have happened with fine silver. I don’t use gold filled. Don’t use
base metals. It’s possible that I’ve left the piece in the pickle for
too long, but it hasn’t required sanding - all I have to do is flux
the whole piece, heat & pickle again. I have tried pickle/peroxide
combo - doesn’t work. I’ve tried new pickle - doesn’t work. But I can
use same pickle - as long as I have fluxed the entire piece again,
heated again & then pickle - the piece come out fine? The fix is easy

  • just can’t figured out what I did wrong in the first place.

Thanks for all of your help.
Sheila

My experience is that if the piece is in the pickle too long it will
begin to turn gray. Longer in/more gray it gets