Hi guys
Just wondering what happens to the diamonds that get burned or
frosted when heated. Do you throw them away or use them? Also, can
you repair a diamond that is frosted from overheating? Would not
these damaged diamonds be good for practicing setting with or not? I
am curious if they are somehow recycled.
Thanks
Karen Bahr
Karen’s Artworx
Just wondering what happens to the diamonds that get burned or frosted when heated.
Plural? diamonds? More like it should be “diamond”. singular. Once
you’ve done this once, why would you make that mistake again?
OK, I’m overstating the case, as I too have burned more than one.
But seriously. All you have to do is be sure they’re properly clean,
and properly coated with a flux or similar protectant, and think
through a job so you know what you’re doing first, in terms of
avoiding overheating, and this should not be a common situation. It’s
avoidable, and costly when you don’t take the proper precautions to
avoid burning the stones. It’s not usually an “accident”, beyond the
first couple “learning experiences”. After that, it’s haste,
stupidity, carelessness, and the like, all of which perhaps SHOULD be
a bit painful…
Do you throw them away or use them? Also, can you repair a diamond that is frosted from overheating? Would not these damaged diamonds be good for practicing setting with or not? I am curious if they are somehow recycled.
If they’re tiny, toss em, practice with em, make a diamond tipped
scriber or other tool with it, or save it as a reminder to clean your
diamonds before heating. If they’re big enough to justify spending a
bit of money to fix, they can be repolished. They loose a little
weight in the process, but not all that much. Not worth doing with
melee in most cases, but for larger stones, it’s routine. “larger” of
course, is a variable definition depending on which cutter you’re
talking to, and the original quality of the stone.
The main thing to know is that the damage is usually just the
surface being frosted. Inside, they’re generally unchanged unless you
quenched them and shattered them in the process.
You could us them for practice setting if you want, if they’re too
small to warrant repolishing. But for me, I’d guess there are better
stones to practice with. Try synthetic rubies, for example. Makes it
very easy to see just where the metal is, so learning to work cleanly
without flanges, fins, tool marks, etc, is easier than with stones
the same color as the metal (I’m thinking practice with pave methods
in this instance). Or practice with something fragile and cheap, like
glass rhinestones. When you’ve got the skill to set those securely,
but without breaking them, you’ll know that you’re not likely to be
breaking the more durable and costly stones.
Peter
Larger diamonds, with enough value to outweigh the added costs, can
be re-pollished by a diamond cutter, as the “frost” is on the surface
of the diamond. Re-pollishing is a very specialized skill, and not
inexpensive. Smaller ones I have no idea what they are good for,
although I have a couple of shaping tools made from small chipped
diamonds, and I’m sure 1 or 2 burnt stones could serve the same
purpose.
My friend owns an electrical contracting business. He’s dumbfounded
at how cavalier I am about lost (or damaged or inferior) diamond
melee. In his biz they go thru alot of those little screw on
connectors for wiring. If they drop some, no big deal, they grab some
more. So when he says, “Neil, how can you not care? They’re
DIAMONDS?”
I simply answer, “They’re wire nuts my boy, mere wire nuts”.
Unless the stone has some size/appreciable value it doesn’t pay to
repolish. A fifty pointer, yes repolish, a five pointer, no.
That being said, I do have a small jar of dodgy diamonds, I use them
for repair of dodgy pieces. Not because I’m cheap but because where
can you order one or two dodgy melees?
Just wondering what happens to the diamonds that get burned or frosted when heated. Do you throw them away or use them?
Karen, if it should happen that a larger stone were burned, which in
my case it would not - just too careful for that - it can be
re-polished, though of course then it’s not the same stone. For melee
and also chipped stones there are guys who come around periodically
and pay $5/ct. for that. They grind them up and use them for diamond
cutting. That’s dirt cheap, yes, but look at the cost of grit on Rio
or somewhere - plus if it weren’t for them it would be $0/ct.
Thank everyone for answering my question on the damaged diamonds.
The reason I asked was that I teach rocks & mineral classes to the
Grade 3 students in and around Calgary and I am often asked to make
up hardness testing kits for them. I have found it incredibly
difficult to find inexpensive diamonds to use to make these and of
yet have not been able to put these together. I have a couple of
rough diamonds that are not gem quality and are only about 4-5 mm in
size. In a mineral box with the magnifying top the kids can see one
in a cube shape (yellow in colour) from South Africa and one in an
octahedron shape (black in colour) from Australia. I have only ever
found these two and if I remember correctly, they cost about $10 a
piece 15 years ago. This way the children can at least see what a
natural diamond actually looks like. For the hardness tests they
could be damaged cut stones or natural rough stones. Many of our
schools cannot afford expensive samples and for hardness testing
they don’t have to be large. I do have to make a little profit on
these as well. I was hoping this might be a way to get some
inexpensive samples if they were no longer useful for making
jewellery out of. 
Oh well.
Thanks again
Karen Bahr
Karen’s Artworx
I am a Technology Ed teacher and use to doing things on a low budget.
Have you considered asking a tile contractor for a used up diamond
abrasive blade or going to a home center like lowes or home depot and
purchasing a new one? I’m not sure how the diamonds are attached to
these, but there are a lot of them on a blade like this. Maybe you
could have the blade broken into pieces for the hardness kits. Just a
thought…never tried it.
Matt
I have only ever found these two and if I remember correctly, they cost about $10 a piece 15 years ago.
Karen, you could have my chipped diamonds for dirt cheap, but I think
you can do better than that. Mine are tiny, for one thing and I don’t
have much right now. Ebay… Jewelry and watches/loose
gemstones/diamonds/rough diamonds and then 'Buy it Now". As I write,
there is 10 cts. of 1/3 ct size for $95 (26-33 pieces), 5 ct., 1mm
size 300-400 per lot for $30, 35 black diamond beads for $59.99 -
lots more if you look carefully. Those are Ebay stores (Part of using
Buy it Now…), not bozo idiot people. I had need to go looking for a
crystal, and found this, lately…Since you need them for
utilitarian purposes - not clarity/color/etc. you should be able to
do pretty well there…
Karen_Bahr
We here in India add 8% boric acid solution to the investment mixture to prevent the diamonds from frosting. But this creates a permeability problem in the investment powder & give a very rough surface… But the diamonds do not frost or burn… The procedure is to mix exactly % Boric Acid powder in ltrs of water & boil the solution till all the powder gets dissolved. This mixture is let to cool.
When you are preparing for investing you just take 50% of this Boric Acid solution & addit to 50% fresh water before mixing thoroughly & use it with Investment powder in wax set trees… to get the required results. This process will prevent your diamonds from Burning & Frosting…
Regards,
Prakash V PaI
INDIA.
Dear Karen_Bahr… Hii
Kindly ignore my earlier & refer to this reply as I missed out on mentioning the mixing figures.
We here in India add 8% boric acid solution to the investment mixture to prevent the diamonds from frosting. But this creates a permeability problem in the investment powder & give a very rough surface… But the diamonds do not frost or burn…The procedure is to mix exactly 16 % Boric Acid powder in 1 ltrs of water & boil the solution till all the powder gets dissolved. You can make at least 50-100 ltrs of this solution & keep it aside This mixture is let to cool. When you are preparing for investing you just take 50% of this Boric Acid solution & add it to 50% fresh water before mixing thoroughly & use it with Investment powder in wax set trees… to get the required results. This process will prevent your diamonds from Burning & Frosting…
Regards,
Prakash V Pai
INDIA.
Can I inquire your burnout temoerature cycles & times that you use with the boric acid additive solution. Also what metal alloys you typically use and temp if you know it.
I’ve tried casting small gems in place before…with some success, but with the diamonds - the burnout temo was 1200Fish, and shoukd not have exceeded 1125-50.
Thanks
Eileen
Hi Eileen Webb…
The Burnout cycle is as follows…
150 Deg C - 60 Minutes
150 Deg C - 60 Minutes HOLD TEMP
300 Deg C - 60 minutes
400 Deg C - 60 minutes HOLD TEMP
550 Deg C - 60 minutes
600 Deg C - 60 minutes HOLD TEMP
600 Deg C - 180 minutes ( Start casting at middle of this stage)
600 Deg C - 180 minutes
600 Deg C - 360 minutes ( Hold till casting is complete)
The above Burnout cycle is used by me for stone in place castings. As you do not need more than 600 Degree Celcius / 1112 Degree Farenhiet ). Stones will not burn at this temperature.
Also Do not forget to use INVESTMENT POWDER which contain Boric Powder addition. This addition can be up to 5% max from the suppliers. You can directly cast with this powder OR you can adopt the below process.
To a litre of distilled water/ normal tap water, add 16% boric powder & boil the liquid properly. Let it cool. ( It is better to cool this solution & check for residual crystalisation of Boric Powder left over in the solution. Filter the same).
On cooling take 50% of this solution & add 50% of distilled water & mix thoroughly. Add INvestment Powder & mix it under vacuum for specified time by the suppliers & then pour it in the flask. Vacuum thoroughly & let it settle for two hours at room temperature. Once dry, keep the flask in Furnace & switch ON the furnace. Cast next day morning when your flask is at 600 degrees / 1112 Deg Farenheit.
QUENCH THE FLASK AFTER AN HOUR OF COOLING & CHECK THE RESULTS.
DO KEEP ME POSTED about the results…
Regards,
Prakash V Pai
INDIA
Hi Prakash
Thanks so much for the information. My burnout is in F vs C. I’ll compare the two and take it from there.
Eileen
The last diamond I burned I hit a 1 pointer and turned it into CO2 because I got too close with my laser beam…
.
I do have some that I overheated and honestly I use them since they are small and not worth re polishing to show people what happens when you do hit a diamond with a laser beam. People think it’s so cool.
Viola
Guys send all the frosted & chipped diamonds to INDIA … as we recut & re polish them for dirt cheap rates…
JUST JOKING…