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Citric acid turned metal pink


#1

I had a white metal bangle that I thought was sterling but ended up
turning pink in a citric acid pickle. Is this bangle made from steel?
Also, is the pickle solution now bad? Will it turn any sterling
silver items I put in there pink?


#2

I had a white metal bangle that I thought was sterling but ended up
turning pink in a citric acid pickle. Is this bangle made from
steel? Also, is the pickle solution now bad? Will it turn any
sterling silver items I put in there pink?

Usually, things turn pink in pickle when the pickle is used and iron
is introduced to the pickle while the piece is in it. A reasonable
test would be to put a known scrap of sterling in the pickle ans see
what happens.

In my experience, copper blush from the pickle is easily removed by
a short soak in hot pickle with about an equal amount of drugstore
peroxide added.

Noel


#3
I had a white metal bangle that I thought was sterling but ended
up turning pink in a citric acid pickle. Is this bangle made from
steel? 

while iron is the most common offender in causing copper to plate
out in the pickle, it’s not the only one. Any other metal that’s both
able to be attacked by that acid and is more electrochemically active
than copper, will do it. Zinc, for example. If your bracelet is one
of the “white metal” alloys other than silver, it might do it all on
it’s own. Or, if sterling, but rhodium plated, there might be an
underplate under the rhodium, or some other plating instead of
rhodium, that might cause that reaction. As with “iron in the
pickle”, these reactions occur when metal dissolves in the pickle,
forcing the less reactive metal (copper) to come back out of
solution. The contaminating metal, once dissolved in the pickle, no
longer has that effect, so once the offending metal item is removed,
the pickle won’t continue to plate out copper on the next thing you
use it for. At least not unless it’s gotten very used up and
contaminated. There does come a point where there’s so much various
metal oxides dissolved in the pickle that it no longer leaves good
surfaces, but by then, usually it’s discolored enough you know the
stuff needs to be replaced.

Peter