i use Liver of Sulfur in Gel Form to oxidise my jewellery. i add
just a little bit into hot water and then add the pieces, checking
the status, as i have learned, that if i leave it in for too long it
starts to “peel off” on some places and that looks patchy. i always
clean and tumbler the piece before i oxidise, to make sure there is
nothing on the surface that would stop the liver of sulfur to get to
the silver surface.
once i have nice deep grey color i take the piece out and wash in
clean water, to give it a nice shine i either put it in tumble for
about 3 minutes or i just dip it into baking soda powder and rub the
surface with the powder a bit, which gives the piece very nice deep
black shiny finish.
you can then with fine sand paper sand a bit off, just to show the
contrast between silver and oxidisation. hope it helps,
have fun making jewellery,