Casting with solder contaminated gold


I wanted to know if you have any info on the pitfalls of casting
with solder contaminated gold. I need to have documented facts in
order to get the higher ups to understand the problems they are
causing by casting with : solder/ enamel/ and possibly rodium
contaminated metal. But mostly solder.

James B Friedman

As far as I remember, you can cast with up to 50% ‘used’ metal, of
that, it is preferable to avoid solder in it because it causes weak
points in the jewelry. I’m not sure if it can lower the caratage. But
in any case, the rule is not more than 50% old metal or you will end
up with brittle and porous castings. I worked for a guy once who
didn’t go by that rule and his silver castings were easily broken,
especially when rings would get impurities in the shank section,
making them break along the impurities.

Jeanne Rhodes Moen
Kristiansand, Norway

Porosity and Karat content come to mind. Both are pretty easily
seen if the gold is too contaminated.


Take a look at the FTC regulations on how much solder is allowed to
be in a peice of jewelry. Only a very small amount is allowed,
though I’m not sure the exact amount because it’s not a strategy I
pursue. There are myriad technical reasons why one shouldn’t use
solder in casting alloy, but if you have to argue with them about
the merits of quality, you’ll probably never win out. However, the
threat of breaking federal law is a bit more compelling, even though
I haven’t heard of anyone getting busted over solder. Too bad, too.