G’day - yet another tuppence worth! I have a bit of a suspicion
that the grey result on etched sterling could be akin to fire
stain; the copper causing the problem. Have you thought of using
a plating-off technique? OK, so the dreaded cyanide is
necessary, but you use only about a 5 - 10% solution and a low
applied voltage, giving a very low current flow, and a bit of a
stir every so often and a gentle brush with a soft painting brush
or a feather. The work connects to the positive electrode, and a
bit of stainless steel to the negative side. So don’t be too
scared of cyanide; that is, use common sense, keep it locked away
from children, don’t keep it in drink bottles, and label it
POISON: CYANIDE in large letters. Don’t drink it (!!!) and
since the bubbles of gas emanating from the work give rise to an
aerosol, dispersing a (very)little of the cyanide liquid into the
air, you shouldn’t breathe too much of it; use adequate
ventilation. Wear latex or plastic gloves if you have cuts or
sore places. I’ve used it many times - and I’m 75 and I don’t
think that’s the cause of my needing a new knee! Cheers,
/\
/ / John Burgess,
/ /
/ //\ @John_Burgess2
/ / \ \
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