may I ask why you "pickle" the wire in this process. I understand
annealing the wire to make it malleable again, but why pickle it?
Are you depletion gilding it to raise the fine silver? In other
words, is the "pickle" step a functional step or an aesthetic step?
Don’t know about Michelle, but pickling would normally be routine
practice after annealing, if the annealing is done by means that does
not prevent oxidation. If you’ve protected the silver with suitable
fluxes or the like so it does not oxidize during annealing, then all
you need do is remove the flux, which sometimes can be just hot
water. But otherwise, if you don’t anneal, you’re working with
blackened cruddy looking metal, not silver looking metal. So the
pickling would be done just to keep the silver looking like silver.
That’s both functional AND aesthetic. Depletion gilding is an effect
you can get by repeated careful heating, generally at temperatures
not quite as high as usually used for torch annealing, hot enough to
cause oxidation of any surface copper, but not so hot that copper
starts moving around, which would tend to negate any surface
depletion from cumulatively building a thicker fine silver layer.
Normally, annealing and pickling once after cold working, even if
that whole sequence is repeated, doesn’t appreciably increase the
thickness of the fine silver at the surface, simply because when you
cold work it, you’re messing with that surface, and when you then
anneal it, (hot enough for recrystalization), diffusion of copper
during that process pretty much negates any buildup of increased
amounts of fine silver at the surface.
Of course, you don’t HAVE to pickle it each time if you don’t want.
But you’ll just make more work for yourself later.
Now, if you’re annealing without flux coating, then you are also
building up a layer of fire stain, which WILL get thicker with
repeated operations, so annealing in a manner to avoid oxidation at
all, is the best plan. This keeps the silver clean, keeps you from
having to deal with fire stain later, and does not cause any
depletion gilding because you’re not oxidizing any of the surface
copper and then removing it.