A solution of Calgon water softener (liquid or powder), salt, water,
glass or plastic container, aluminum foil on the bottom of the
container, tarnish is removed as soon as the silver touches the foil.
Does not affect patina, I only used LOS, so test please.
1 or two cups cold water, Tbs or Tsp salt, Tbs or Tsp Calgon, put
water and water softener in non metallic container.
We used this for tens of thousands of pieces of sterling jewelry over
at at least 15 years, every and any type of gemstone, pearl, shell,
rock, mineral, some say no amber (I did it quickly with no problem).
Take out foil keep covered when not in use.
The foil will dissolve if left in.