Ariella, Best not to quench in pickle when hot. Quench in H2O then
put in hot pickle.
This metal sounds like something other than silver. Even if easy
solder was used, heating to annealing temp. should not weaken solder
joints. Did you fabricate, or someone else who said it was sterling.
That has happened to me when someone told me the piece was silver. It
immediately slumped with hardly any heat. Ooops. Not silver!
Usually pickled silver when removed from pickle comes out almost
white, with a slight gray tint. Use baking soda, water with soft
toothbrush to remove slightly and give a slight sheen. Or just
between your finger tips. Heating until the brown disappears sounds
correct to bring up fine silver.
Try on scrap first, but it should work if sterling.