Hi everyone, Here’s a mess I got myself into which may amuse you.
In my own defense let me explain that I’m about 99 44/100 percent
self-taught. This means that very often I’m re-inventing the wheel
when I make something. This can be instructive, where "instructive"
usually means that you’ve just learnt at first hand why they don’t
normally do it that way.
Now here’s my mess. Part one is, I’m making a set of wedding rings
for two very good friends; cut a really bright pink Maine tourmaline
for hers and a green oval one for his. His will be bezel set. No
problem there. Hers is about a 3 mm square emerald cut for which I
built a set of prongs. Prong settings give me grey hair anyway. These
prongs aren’t as pretty as I’d like 'em to be so I want to do a
re-cast (in cuttle fish bone) to file out new ones from.
That’s part one. Part two is, I’m using unorthodox metal. It’s the
result of an experiment in quartation (when you alloy gold scrap down
to less than 25% gold prior to subjecting it to acid). The low-gold
quartation alloy had a really subtle attractive moon-glow sort of
soft yellow, much more to my liking than the standard 14 or 18K
"shopping mall" gold. My friends also liked it. Guesswise it would be
about 80% sterling silver, the rest gold.
(One of its other interesting aspects is it melts at below the
melting temperature of medium 14K solder. “Hers” Mark I bit the dust
that way. Oh well I knew about that and I do have some extra low
temperature gold solder. Just forgot to use it the first time.)
Now here comes the real problem. What I’ve been doing is casting
this stuff into ingots in cuttle bone and then rolling it down. That
worked well for a while but recently the cast has come out unsound,
bubbly. I tried re-melting in charcoal; I tried “poling” the melt - a
semi-medieval procedure in which molten metal is stirred with twigs
of green wood to de-oxidize it. Neither cured the bubbles.
So as a last resort just now I added about 1/2 gram of zinc (to
about 25 grams of the alloy). I’d heard that the zinc would help make
for sound metal for casting and that it would burn off if you kept
the heat on it. Unfortunately either my memory is flawed or the
itself is suspect. Probably the latter.
What I’ve got now after adding the zinc is essentially what the old
goldsmiths called spelter, and used for solder. It is excessively!!!
low melting. So low that there’s no way it can be soldered at all
(short of lead solder, and that’s out).
So my question is, using the kitchen table melting technology I have
available to me (acetylene torch, borax, charcoal, graphite
crucible, and a kiln that goes up to 1800 F) can anyone suggest a way
I can de-zinc this stuff?