Hi all,
I have to set a 10ct Kunzite in a 18kt bezel next week. This stone
has been in the family for 35 years and to say the least, I am a bit
anxious.The girdle is thin and the stone is an elongated oval. I
have never set a Kunzite before. Has anybody had any experience
setting Kunzite? Anything I have to watch out for?
Yours sweating, Hans Meevis.
http://www.meevis.com
Hans,
I haven’t had any particular problems, but kunzite does have perfect
cleavage so you can split the stone in two, though I would doubt it
will happen with the usual care taken in setting any stone, unless
your mounting is similar to an iron maiden. 
Brian Corll
Vassar Gems
Kunzite absolutely fades gradually in sunlight - permanently, first
of all. Keep it out of the sun, and it should never be put in a
store window. Strange but true. As for setting, think topaz - even
periidot, but harder. It will chip if you wink at it. Very fragile
stone, not so much in wear as in setting. I’d say just be very
careful and take your time - and don’t use the hammer handpiece, or
not much.
I have to set a 10ct Kunzite in a 18kt bezel next week. This stone has been in the family for 35 years and to say the least, I am a bit anxious.The girdle is thin and the stone is an elongated oval. I have never set a Kunzite before. Has anybody had any experience setting Kunzite? Anything I have to watch out for?
Hi Hans. With a hardness of 6.5 or so, kunzite (spodumene) is easily
scratched, but you probably knew that already. But couple that with
two perfect cleavage directions, and you have got a real problem. My
first suggestion is to use a 22K bezel instead of 18K and be very
careful. Yes, I know that 22K is very soft for gem mounting, but the
stone in question will be affected as easily, or more so, than the
metal if knocked around at all. If it’s in a pendant or brooch, it
won’t really matter if you use 22K. If it’s going to be in a ring or
bracelet, the kunzite’s chances of surviving long is slim indeed.
Either way, kunzite tends to fade in sunlight, so it should be
carefully worn only at night, anyway.
The second suggestion is to make certain that, if you do use the
18K, just make sure it is annealed to dead soft. Best of luck, Hans,
and please post a photo of it when finished - I’d love to see it.
James S. Duncan, G.G.
James in SoFL
I am wondering, is the color fading is permanent?
Either way, kunzite tends to fade in sunlight, so it should be
carefully worn only at night, anyway.
James S. Duncan, G.G.
James in SoFL
Either way, kunzite tends to fade in sunlight, so it should be
carefully worn only at night, anyway.
I am wondering, is the color fading is permanent?
Yes, basically. But since pale colored kunzite may be irradiated,
then heated to intensify its color, it may be possible to restore
color intensity to a faded piece. Has anyone here heard of this being
done?
James S. Duncan, G.G.
James in SoFL
since pale colored kunzite may be irradiated, then heated to intensify its color, it may be possible to restore color intensity to a faded piece. Has anyone here heard of this being done?
Faded Kunzite may be irradiated with Cobalt 60 Gamma Ray
Irradiation.
It will turn a fantastic neon green color (that will fade in
sunlight in a very short time - to a very light color). Then the
Kunzite can be heated in a stoppered test tube over a bunsen burner
or in a Kitchen oven and it will turn pink again.
I saw a dealer do this once. He had a parcel of beautifully faceted
Kunzi te and he put it in the oven to “tweak” the pink color. The
phone rang and he forgot the stones in the oven. They became a
parcel of beautifully faceted clear colorless stones - but not what
he wanted.
After irradiation, they turned a fantastic neon green - rivalling
Paraiba Tourmaline - but the color faded quickly in sunlight.
After putting them back in the oven and paying careful attention,
the stones turned back to their characteristic pink color.
I do not know if this process would work on a stone that is already
mounted in a setting due to the different heat conduction rate of
the setting that would cause hotter points on parts of the stones
when heating. And I do not know how the Cobalt 60 Gamma Ray
Irradiation would affect the metal of the mountings. It would
probably be more intelligent to remove the stone from the mounting
in order to irradiate it.
One other consideration is that the treatment laboratories usually
have a minimum charge which is on the order of USD$ 1,000.00 per load.
Unless one can find a University Research Laboratory with a Cobalt
60 Gamma Ray facility and which charges a lower minimum fee for a
small load - it is probably not economically feasible to treat a
single stone. Of course one could find a kunzite dealer and ask him
to treat the jewlery piece along with his next load to be irradiated.
Best regards,
Robert Lowe
Lowe Associates - Brasil
Gemstones, Rough, Specimens
Tucson - Jan 31-Feb 5, 2007 - GJX booth # 205
e-mail: robertplowejr_AT_juno.com