Clean Sterling - this can include metal with solder, but not
mixed metals, or parts containing adheisoves or stones.
Junky Sterling - Used sandpaper, sweeps, metal with odd things
glued or soldered to it.
18KG
14KG
A million years ago, I worked for a goldsmith who refined the filters
from her heating system, the bags from her vaccum cleaner, and the
entire rug when she remodeled the studio. She did get a small
fortune. I, however, do not use much gold, and would not get much $$
for such careful measures.
Check on Hoover and Strong's web sight for info on refining. There
is also a thread on refining on Ganoksin.
That’s the best advise. I can tell you what we do, though. We have a
big fiber drum from the refiner for floor sweeps, polishing filters
and such. We have a smaller container, about 1/2 gallon, for bench
sweeps, and if I sweep the floor by my bench I might put it in there.
We keep our filings and scrap separate and clean, and recycle them
(melt them), but anything metal that is suspect for that I put in a
glass vial that’s pure metal - no dust, lint, etc. That’s because we
get a better return the cleaner it is, with our guy. Less work for
them = more money for us.