Dale, Firecoat the pieces and melt them. The dianonds will come to
the top. Lel it cool, and pick ihe diamonds off.The firecoat will
protect the diamonds to around 1800 deg.
Not all the time, it won’t. If you were to get consistantly good
recovery of undamaged diamonds this way, I’d have to say you were
bucking the odds big time. Out of curiosity, I tried this some time
back. Decent quality melee, very well cleaned, lots of boric acid
firecoat. Five stones. Two were fine after. One badly burned to a
whitish surface. Two visibly less bright, no longer matching the
original polish. Not a good sucess ratio. And if there’s even a
trace of dirt on the stones, forget it. They’d be toast. Well, Ok.
Some of the 10K and 14K yellow alloys melt low enough you might get
away with this. Sometimes. But don’t try it with 18K. And I’d guess
many of the white golds wouldn’t work either. That sample I mentioned
above was 14K white gold…
For removing small melee in pave or flush set, or similar setting
styles without a lot of metal holding, you can often remove them with
just a sharp push from the back, if their drilled through under the
stone, as is usually the case. A beading tool placed over the culet,
and shoved hard with the hand removes most. No hammers, please.
That’s too much. If it doesn’t come out with a sharp push, you need
to cut some metal away first, but from the description of lots of
teensy stones, this method is fairly quick. I know this sounds risky,
but it’s less than you’d believe. While the girdles of diamonds can
be fragile, and a sideways blow to the culet can chip it, direct
pressure straight at the culet is addressing a very strong direction
in the diamond. Consider that scientific equipment used to study very
high pressures, which often is done with diamond “anvils” For all
intents and purposes, that amounts to pressing two diamonds together
at the culets, and watching, through the diamonds, the results on
whatever is between. The culets don’t chip. Yes, you may break a
few, but likely those will be the highly flawed junk melee anyway. I
find I break fewer melee taking them out this way, than I do if
cutting away beadwork with a graver to take them out.
Lots of stuff is set in channels. In rings with channels running
paralell to the finger, just clip the shank at the bottom, and bend
the whole ring to a smaller diameter. That makes the channels wider,
and the stones just fall out. Often, other types of settings can
similarly be just bent, usually after cutting some supporting
structure with nippers, to allow the stones to fall out of the
loosened setting. Much easier than trying to cut away or bend back
the holding metal.
For prongs, prong lifters of prong lifting pliers are fine if you
wish to save the mounting. If you’re scrapping it, sharp side cutters
can clip the prongs below the girdle faster and simpler than pulling
them back. Some flush cut side nippers make very good prong pullers
too, doing double duty.
But even quicker is to NOT remove them at all. Assuming you’re going
to scrap out the metal, simply send the stuff as is, with diamonds,
to your refiner. Most good ones offer the service of acid refining
the jewelry directly, without first melting. You wait longer for
settlement, since they are actually refining your metal to order,
rather than assaying it and paying from the assay. The acid
dissolution removes the gold into solution, and the diamonds,
completely unharmed, can be recovered from the sediment left at the
bottom of the beaker with little effort, and no risk to the stones.
Not all refiners off this service, but many do, and though there’s a
little higher cost for it, it saves all the time, and occasional
chipped stone, for manually removing the diamonds. Some colored
stones can be left in the jewelry too, though of course not all.
Anything not bothered by aqua regia can be treated this way.
This method is probably not needed when you’re dealing with larger
melee or individual larger stones, since with just a few, it’s easy
to take them out and then you’re done. But with the inexpensive stuff
that’s set with hundreds of tiny junk diamonds, or for that matter, a
lot of small good quality stones, this is a cost effective way to
deal with it.