Theresa, I have noted a lot of differences in stones in the last
two years. My experience is that stones that have been
irridated and heated are much more brittle. Facet edges chip
easily and it is difficult to get a scratch free polish.
Morganite beryls have been especially finicky. Some quartz
materials can cause problems. The new lemon quartz and green
quartz are in this category. Sapphires have not been a problem.
No one that I know of has ever done a study to find out if
heating and radiation effect the durability of the stones. Some
stones are put through the process several times to furthur
enhance them. Does it effect the characteristics of the stone?
I do not know for sure.
Gerrry Galarneau
Boy, I’m with you there, Gerry. I haven’t been following this
thread, but I have noticed a lot of difference in stone fragility
this past year. This year, I’ll track my cutting expenses to
better monitor the problem, but I would guess I lost over fifteen
hundred bucks on recutting and loss of income from carat weight
this year. That is only counting the ones that I didn’t feel I
was at fault on - there were others where it was most certainly
my own stupidity. I mostly deal with higher end rubies and
sapphires and feel they are much more fragile than in the past.
My guess is that they’ve been over heat treated, but I’m a simple
goldsmith, not a gemologist. I’ve been setting stones for a
heck of a long time now, and design and make each piece for the
stone, so it’s either me or the stones, and I don’t think it’s me
(of course). It would be nice to see some kind of study done on
this, because in my mind it’s becoming a much more serious
problem than it used to be. There is no way I’d heat on an
expensive ruby or sapphire these days, and I used to do it all
the time.
Mike Rogers
I was taking a refresher course from the GIA 4 years ago in
Tucson on new gem treatments and synthetics and I brought up this
very problem to the GIA people there and they all looked at me
like I was nuts. But I also believe that a lot of material that
has been heated is more fragile than unheated. We just have to
use a little more care in everything we do, I guess.
Daniel R. Spirer, GG
Spirer Somes Jewelers
1794 Massachusetts Ave.
Cambridge, MA 02140
@spirersomes
Hi Dan,
I was taking a refresher course from the GIA 4 years ago in
Tucson on new gem treatments and synthetics and I brought up
this very problem to the GIA people there and they all looked
at me like I was nuts. But I also believe that a lot of
material that has been heated is more fragile than unheated.
That doesn’t suprise me. I don’t think many folks at GIA or
their gem lab are faceters. They know lots abut the theoretical,
but are a little short on the pratical side.
Dave