Don't anyone take this as gospel. What's written is wrong, but
It is so easy to proclaim that this is wrong and that is wrong. How
about some proof. You saying that heating diamond and cooling it
rapidly will damage the diamond. What is the basis for your
statement? All the properties of diamonds saying that it is you who
are wrong! Please elaborate your position.
Leonid Surpin
There are many designs that ~require~ soldering on diamonds to
execute the design.
That is most interesting Mr. Donivan,
Could you maybe show some pictures of a design that requires
soldering on a diamond to execute ?
Maybe one that you have made?
Clear pictures on your blog would be most appreciated.
Hans
Most of us have had an “accident” with a small diamond and have chips
in our studios. Just put one on a soldering block and watch carefully
as you heat it up. Scary wasn’t it?
How to make a diamond disappear… enjoy 
Regards Charles A.
I do successfully solder with 19K weld, 1000 plat and 1100 near
diamonds. I have a friend who does also. We have tricks that work
well. So I am saying this from experience. I do work with stones that
are over $100,000.00 and do repair around melee regularly. And I
braze wire down to 3 thousandths of an inch. I’ve never had a need to
but I think I want to try brazing wire one thousandth of an inch just
for the heck of it. As one person said, soldering (actually brazing)
around diamond is routine in the industry and that is true. In fact
there are companies that make jewelry where the diamonds are actually
cast into the ring casting itself. However I am not going to tell
anyone what to do outside their skill levels. Although, as the person
who looked for help on this found, it was more his fear then his
skill at question…hey, congratulations!. There are days that I have
to follow my instincts of the moment and if that feeling says, Jim,
your focus can’t handle this degree of challenge right now, then put
it off till your focus is impenetrable by outside forces of
distraction. Then I will platinum braze around stones… no problem.
However I will take the steps (which in conjunction with other safe
guards, together) that I have discovered do work for me… the key
word is “work” for me. It does also mean being able to do quick and
efficient soldering with no waste of time. I do have to say from
(personal) hind site when I was younger and less skilled, sometimes
it was hard to recognize what is ultimately doable if you have no
point of reference in order to recognize and understand the practice.
After working in jewelry, pushing your skills and techniques and
accomplishing what people say in theory that doesn’t work, you push
the boundaries of the art and what you personally are able to
accomplish for your client. Do it enough and one does develop a
"sixth sense" around what can be and can’t be done. When the
practitioners find a working process then the theorists need to find
the error in thier theory and rewrite it. However I will still say,
if you are not comfortable, remove the stone. And that way you are
being safe and you are honing your skills of removing and replacing
stones!
James F. Conley
Can welding or soldering a platinum ring be done near stones?
It is not possible to weld near stones using a torch. Even the lowest
temperature platinum solder will burn the stones. However, it is
possible to weld using a laser next to stones. At times, soldering
can be done with a gold solder when replacing a head on a
semi-mount".
So, as there are some on this forum with 30-40 years of experience
and this is a forum for sharing, please provide specific techniques
or better yet,a youtube video,. Make our lives easier, please.
Richard Hart G.G.
Denver, Co.
I for one, would not torch a $150K diamond, no matter how clean the
stone, no matter how infallible I thought I was. If the setting needs
attention for whatever reason, make a new setting, or at least pull,
repair and reset. Playing against the odds is OK with the lottery
where it only costs you a buck when you lose.
My experience, which is all I can relay, is that smaller diamonds
mostly frost on the pavilion usually near the girdle. It COULD be
heat transfer from the mounting. Or it could be that’s where the
oxygen is, the crown being immersed in firecoat in a reducing flame
and the belly maybe not so well protected because you cannot
guarantee that you have 100% firecoat coverage under a mounted stone.
That is why I believe small stones have a higher rate of toasting.
The one exception that sticks in my mind is when my apprentice
decided he knew better than me and used plat solder to retip after I
purposely told him not to, that crown looked like beach glass.
Let me clarify my 20KWW comment. Yes its hotter. The advantage is
that of flow control. With care one can use the torch to literally
but gently pull the molten solder down along the outside of the
prong. (what good is a new heavier tip if the prong body itself is
still thin?) I would specifically recommend against this for any but
well experienced torch wielders. However I would not use 20K to add a
post or bail, no reason to. Again though, I would not torch an
extreme value stone.
I can’t say I’ve ever had a diamond break under heating/cooling. So
now I’ve probably jinxed myself by saying so, right?
I braze wire down to 3 thousandths of an inch
WOW talk about torch control. Under what circumstances do you find
jewelry with wire that thin?
design that requires soldering on a diamond to execute
I see a lot of diamonds by the yard where the bezels are soldered
around the stones rather than ‘set’. This one maker I’m thinking of
specifically, even torches delicate stones, topaz, beryl, etc. I
can’t figure out how he manages it but he does. I know he uses
optical type wire and solders in place with an aqua torch, or so he
says. Sometimes even very friendly jewelers might withhold key
process.
And he only charges $16 per including bezel wire and joining to chain
(chain and stones extra). I have some of his stuff in my cases now.
Could you maybe show some pictures of a design that requires soldering on a diamond to execute?
Sure Hans, but it’s easier just to post links here…I’ll see how
many I can come up with, but the first one, for sure, is a good
example:
The E449/11 and the E478/13 have a platinum strip going under the
center stone, channel set with continuous diamonds. That strip is
pre-set and finished and soldered in place after. It could be argued
that the work is possible by setting in place, but that’s not really
true, not to the qualityof this. Plus that would be the hard way. It
was my job to make thisring - I made the one you see… We didn’t
HAVE to do that on the W449/11, but we did because it was easier,
too.
In the case of the E310/4 and /2, below, that’s genuine bright
cutting (not pre-cut). The stones are set first, and the setting
soldered after because it’s in the way of the graver.
The F352/P and the F337/P are “sliders”. The diamond floats in the
channel. The stone is inserted and the channel is soldered shut on
one end.
Not ~on~ the stone in this case, but still solder in place.
Two more pics after the above. Not much to be done but work around
the old piece.
Simlar to the 449, above.
There’s another common circumstance that I don’t find a pic of. Just
lately I did a job that was like a tulip flower with a diamond bezel
set down inside, with a gap around. No way to set it (well) in place
Just my own pics - there are many circumstances out there…
How to make a diamond disappear...
Well, let THAT be a lesson to move your vat of liquid oxy further
away from your pickle pot, lest you make a mistake. 
How to make a diamond disappear... enjoy ;-) http://tinyurl.com/28u4rpa
We have to thank Charles for providing demonstration of how
mis-is spread on the Web. Anybody, even with modicum of
gemological background, would lough at that video, but a person, who
is not a gemologist will be deceived.
So what is wrong with the video, you might ask. Can diamond be
destroyed on contact with oxygen? Yes it can, but unless one doing on
purpose, there is no danger in the course of normal soldering.
The part with industrial diamond exploding - could happen, but they
are not used in jewellery. In jewellery we use single crystals.
The part about cubic zirconia is totally false, because CZ are not
stable under heat. One should never solder with CZ in place.
I do not want to speculate about motives behind this video and the
like, but let me assure that providing is not one of
them.
Diamond has one weakness. It is a sharp blow in cleavage direction.
It is also possible if shearing force is applied in cleavage
direction and temperature exceeds 1200 celsius, crystal latisse can
be deformed, which could result in loss of transparency. But in order
for that to happen in jewellery shop, it has to be very unusual
circumstances, or a very stupid goldsmith.
The lore about diamond damaged by fire comes from cases when diamond
had been damaged previously, but damage was discovered after
heating. Another situation is when goldsmith may think that he/she
working with a diamond, but the stone is something else.
In conclusion, diamonds are formed 100 to 150 miles below the Earth
surface. They ride to the places where they are found, surrounded by
molten rock. The harshness of that environment is difficult to
imagine. When diamond is cut, it experience tremendous amount of
forces, so all crystal imperfections are discovered at cutting
stage. By the time is gets to goldsmith bench, a diamond had been
through everything. As I said, it take a dedicated effort, or a very
stupid goldsmith to damage it after all that.
Leonid Surpin
The part about cubic zirconia is totally false, because CZ are not stable under heat. One should never solder with CZ in place.
I have soldered near bezel set, or channel set CZ, protected by
boric acid and not quenched,sometimes it works and sometimes it does
not which is why I always have replacement stones on hand in case one
cracks. The reason I try is that if I have to remove the stone, that
will create more damage to the metal, easier to bust out the damaged
stone, not so hard to reset a replacement.
Richard Hart G.G.
Denver, Co.
One of those situations that a friend asks if I would repair a broken
chain. About a.75mm 14K white double rope. I wanted to do a super job
for her. I didn’t think a little chip of gold solder holding the
broken ends together was how I wanted it to look. Then I considered
maybe a micro jump ring, but then I thought, can I do better? So I
set out to see if I could actually rebuild the chain there. So there
I was challenging myself. I nipped the two micro jump rings open on
one of the ends. With tweezers, I carefully slipped the two links of
the double rope onto the two corresponding links of the other loose
end. I carefully maneuvered the links so I could hold one of the
links with self locking tweezers which I had pre-ground to needle
like tips and adjusted the tension so it wouldn’t damage the wire it
was gripping, leaving what was a matter of a fraction of a mm
clearance to solder the joint and not have the solder run. Then I
took a #3 tip on my Smith Little torch (oxy/prop.), adjusted it to a
flame that was so small it barely sat on the #3 tip. Next I picked up
a tiny piece of solder (I had two pieces set up next to the chain
links) with a solder pick that I had ground also to a needle like
point. Now was the moment of truth… carefully holding the micro
bead just slightly over and forward of the joint (so the bead would
take the heat first) and heated both up and touched the solder to the
joint. It pulled in and it was soldered. I quenched it and then with
tweezers, manipulated the links so I could then solder the other link
of the double rope. I do have to say, I did this with a #7 optivisor,
my upper body was extreamly tense and I was barely breathing so my
hands would be steady enough. For the amount of time, and I felt like
I was working in slow motion, it would have been cheaper to buy a new
one. But I felt like
it was a moment of challenge to test my soldering control.
Afterwards I measured the wire of the individual links, they were 3
thousanths.
~Believe me, I WILL NOT offer this service to the public!!!~
James F. Conley
We have to thank Charles for providing demonstration of how mis-is spread on the Web.
Ofgs.
Leonid, how is this mis-The demonstration was delivered
to be fun, it has nothing to do with soldering, unless you want to
attempt to solder with liquid oxygen.
The part about cubic zirconia is totally false, because CZ are not stable under heat. One should never solder with CZ in place.
Well the CZ looks pretty much intact, after the same treatment that
was given to the diamonds. Seeing is believing, and as far as I know
Popular Science magazine does not tell porkies.
I do not want to speculate about motives behind this video and the like, but let me assure that providing is not one of them.
You don’t have to speculate, the article comes from Popular Science
magazine, it’s a science experiment. They also did an interesting
article about using a microwave to melt metal.
Diamond has one weakness. It is a sharp blow in cleavage direction.
Well that’s obviously not true, if someone treats the diamond the
same as in the experiment, it will burn away. Being burnt away to
nothing could be considered a weakness.
As I said, it take a dedicated effort, or a very stupid goldsmith to damage it after all that.
Or a dedicated scientist doing an experiment.
Simply take the video as given, it was a bit of fun, that is all.
Regards Charles A.
I have soldered near bezel set, or channel set CZ, protected by boric acid and not quenched,sometimes it works and sometimes it does not which is why I always have replacement stones on hand in case one cracks.
CZ will not crack if heated, but quite often it looses transparency.
Kind of a bluish haze. Degree of damage varies, but if one look
really close, it is there.
Leonid Surpin
Leonid, are you writing about the diamonds I come across, 1/10ct or
smaller, illusion set, full of black inclusions and bought off a
shopping channel? These will shatter if you sneeze at them!
I was resizing a stock ring yesterday, after it had been sold. It
was a platinum knife-edge diamond solitaire, and one of the
shoulders snapped off while I was reshaping it. I was on my own in
the workshop, and I only had one hour before the customer was
collecting. That meant I had to made a decision - risk damaging the
stone, or risk losing the sale.
The knife-edge shoulder needed soldering directly onto the collet. I
used an oxy-propane torch, carefully coated the diamond with flux,
and heated it up to soldering temp.
Result: one soldered platinum ring, diamond intact, no loss of
clarity…etc. It was scary, definately, because the diamond went the
same bright red colour as the platinum, but it worked out OK. If it
hadn’t I would have been in serious trouble with my dad.
I think it all depends on the quality of the diamonds - I was
working on an E/VVS, but if it had been a low clarity stone, perhaps
it would have been more likely to break due to inclusions of other
forms of carbon that are less stable. As someone (Leonid?) said,
fracture filled diamonds would probably go black at those kind of
temps, but a fracture filled stone isn’t a real diamond, in my mind.
In the video Charles linked to, the stones were of a very low grade,
chosen for size and cost rather than appearance. I expect a
chemically and mathematically perfect diamond would fare differently
(if such a stone exists), particularly in a low-oxygen environment.
I’m not a fan of rings cast with the stones in, but does anyone here
know if they can be done with platinum? If so, are they cast in an
oxygen-free environment?
John,
I used to also make mass jewellery like that, and indeed, it is
often easier to solder a diamond ~into~ place, like the ‘slider’ you
showed. I have also plenty of times soldered on small
diamonds,–0.50ct is my cut off point.
However, a design that cannot be completed unless soldering ~on~ the
diamond takes place is one that should be revisited.
Also, I will make everyone of those designs that you gave links to
without any soldering on the diamonds.
That’s just Walmart stuff, I made thousands of those in the past,
all without soldering on the diamonds…
You don't have to speculate, the article comes from Popular Science magazine, it's a science experiment. They also did an interesting article about using a microwave to melt metal.
Science experiments are done to verify a theory, and they always
have a control subject. The video is more like a hocus-pocus. It was
a set up to make a point. Diamonds do not come in contact with liquid
oxygen in daily wear, nor while been repaired. The second stone
wasn’t a diamond but a diamond conglomerate, and they did not bother
to explain the difference, and CZ explanation was a complete lie.
Zirconium Oxide exist in natural form. It is gemstone called zircon.
CZ is a cubic form of Zirconium oxide, which does not exist in nature
( small crystals were found recently ) because it is not stable. In
CZ manufacturing stabilizers are used to make cubic form possible,
but it looses transparency under heat. I guess “scientists”
conducting “experiment” were not aware of these facts.
Leonid Surpin