wrote in message
oups.com...
Without going into the gory detail, I can tell you from personal
experience that it's difficult or impossible to get an acceptible
silver plated surface without the use of cyanide based chemicals. The
same is true for gold and other precious metals like rhodium.

The plating shop I used to use ran a phosphoric gold process, but I have no
clue about how it was applied, nor if it was necessary to do a strike with
cyanide first. They plated to Mil specs, and were highly respected and
well known for their quality. Sadly, I no longer live in that state, so
it would be difficult for me to inquire. Having refined precious metals, I
understand that the introduction of certain metals to cyanide solution can
be trouble. One of the procedures I used to use to recover gold or silver
from solution was to introduce zinc flower. The reaction was almost
instantaneous, with an almost perfect recovery. That can interfere with
plating, just as iron interferes with copper plating from an acid
electrolyte. There's a place for each process, and often they must be used
in conjunction.

You should be able to purchase the materials that you need from any
electroplating supply firm, even in the UK, although as here in the US
they may be unwilling to sell to individuals due to liability
considerations.

That would certainly be my thoughts, too. Still, if you can get someone
to warm up to your project and share with them what you're trying to do, you
never know-----every now and then you encounter someone that takes a
personal interest and can't help enough. And then there's the other
times---------------sigh.

Harold


Harry C.