I dont think so.
Ive used it strait out of old lead acid batteries for most of my
silversmithing yrs.
With no problems.
Afterall, pickling after any hot work such as forging or brazing or
annealing, is just a small part of a manufacturing process. To give
you an example.
One of the things I make are buttons, The fronts I always drop
stamp, generally in 50/1000, in thick material.
Wether in silver or bronze or copper or even brass.
then when domed, the omega has to be brazed on to the back. I use a
jig for this at my brazing station, using esyflow no 1. hand wire
fed. when brazed,I pick up the item with tongs and drop it through a
right sized hole in a jam jar.
the acid is cold but the work is hot so the thermal shock knocks off
most of the flux residues and any oxide formed.
Lets see if anyone can guess why I have the hole in the lid? and not
just an open bowl?
when ive done 30, say half an hours work,I drain off the acid, drop
thebuttons into plain water and boil for 5 mins.
Drain, rinse and dry off.
Then, there ready for polishing, or off to the platers if there to
be silvered on brass.
Obviously silver buttons have silver omega’s. anything else have
copper. Love making real silver buttons!!
Sell very well.
Ted
in Dorset
UK.