First, let me suggest getting Judy Hoch's wonderful little book
"Tumble-Finishing for Handmade Jewelry." I know Rio carries it, as
do several other jewelery suppliers. It's very practical and answers
many questions. Excellent resource and very reasonably priced! (no,
I'm not the author)
Second, did you tumble the green media for several hours before
using it on your finished work? When I first got the media (I have
crushed walnut shell), the instructions were to work the Meta-gloss
(green polishing stuff) into the shell pieces until it was
distributed evenly, then tumble for 8 hours. That evenly coats the
pieces of shell and allows the solvents to evaporate. (one oz
polishing compound to 8 pounds of shell) The shell then looks shiny
but is not sticky.
I rarely tumble more than an hour. It is best to check after 15 or
30 minutes. I have found that there is a slight coating left on the
jewelry, but it comes off with something like 409 or Windex and a
light scrubbing with a toothbrush. (One must be cautious with pearls,
turquoise, and other stones that could be harmed by ammonia.) Any
tags have to be replaced though - they are dingy.
The little pieces of shell DO get wedged in openings and behind
stones. The best solution (thanks to Noel) is to put them in a small
cardboard box, and "shake like a crazy woman." The pieces will almost
always come loose. The box is rigid enough for a good impact to jar
things loose, yet doesn't damage.
Another tarnish removal solution - and more effective - is an ionic
cleaning machine. It takes 15 seconds or so. I use the brand
"Speed-Brite". This method removes tarnish in crevices, so is not
good for pieces with an intentional patina. That can be a bummer.
I think that there is no single best answer. The appropriate
method/tool depends on the piece of jewelry. Sorry you are being
frustrated. Undoubtedly there will be other input. Orchid is such a
sharing community. Also thanks to Hanuman and Ton for their ongoing
work to keep us connected.
Judy in Kansas, where it promises to be a sunny day and maybe even
warm enough to hang the wash out!