I recently had to re-solder the end cap onto an ordinary
Italian-made sterling snake chain, about 1.8 or 2mm thick. After
soldering, I dangled that end in pickle. Ten or fifteen minutes
later when I pulled it out that area was all red - plated in copper,
I presume. What’s the deal here? Is steel used in snake chains in
some manner? It cleaned off easily with steel wool, but I still
wonder what was going on. What do the Orchid experts have to say?