Back to Ganoksin | FAQ | Contact

Glass-filled rubies


#1

Much more on the glass-filled rubies can now be found on the Asian
Institute of Gemmological Studies web site:

http://www.aigsthailand.com/Filearticle/55.pdf

I received this email from GEM-A@MAILTALK.AC.UK and I recommend that
Orchidians who are interested in gemology sign up for the GEM-A list.

Many thanks to Gem-A Mailtalk member Alain van Acker for sending this
link to us.

David Barzilay
Lord of the Rings
607 S Hill St Ste 850
Los Angeles, CA 90014-1718
213-488-9157


#2

David,

I too receive the Gem-A list. it is a great resource for what is
happening in the world. The article on glass filled rubies is good at
helping to understand some of the treating processes used. We need to
know what is going to come across the bench and how to explain these
things to our customers. At this point I do not think that I will
ever put heat to a supposedly safe stone again. The risk is becoming
to great of hitting a treated stone, diamond or otherwise.

Thank you Dr. Ogden, who is behind the list.

Bill Churlik
@Bill_Churlik
www.earthspeakarts.com


#3

Dam, they just keep coming up with ways to make our life more
difficult. Isn’t there a simple test to detect? perhaps water
immersion would make the glass visible?

Ringman


#4
   Isn't there a simple test to detect? perhaps water 

Hi Ringman;

I don’t know of any fluids or special lights that would reveal the
glass filling, but I’ve been able to indentify them by looking at
them under high magnification. What you’ll see is that where the
cracks are filled, the filler polishes down a little, so you see
these crevices and pits where the level drops a bit but it’s
polished. The color is kind of suspicious, especially when you see
one of those dead-on-red rubies in a cheapo mounting. More like the
color of a lab grown, but not as transparent. One trick I’ve heard
they’re doing is taking lab grown material, heating it and quenching
it to crack the crystal, then filling it. Why? To make cabachons!
Usually, good ruby cabbing material is a good color, but not good
transparancy. So, you can get a better margin by fracturing and
filling lab grown than by mining and cutting good cab rough.

David L. Huffman


#5

Ringman,

I have come into this conversation late so I do not know the
original question but let me make everyone aware about glass
fillers.

Any gemstone that is heat treated to improve the color and has
fractures that break the surface has the potential to have a glass
filler.

What actually happens is the flux used to protect the stone during
the heat treatment melts and enters the cavity. This problem is most
often found in rubies but could be found in other gemstones as well
due to the process used.

Greg DeMark
email: greg@demarkjewelry.com
Website: www.demarkjewelry.com
Custom Jewelry - Handmade Jewelry - Antique Jewelry


#6

The observation of telltale gas bubbles and strong purplish blue
color flashes (like in the Yehuda filled diamonds) are plainly
visible with magnification.

I don’t suspect it is too difficult to detect, presuming one has a
good microscope.


#7

Thanks Bill and David for your kind comments about the Gem-A List
with regard to its circulation of about Glass Filled
Rubies.

Glass filled rubies are not the only new headache in our industry.
On my desk at the minute are samples of the green glass beads and
glass ‘gems’ that have supposedly been imported into the USA set in
’tons’ of costume jewellery - the pretty green is due to use of
depleted uranium. (Origin of the glass supposedly Czech Republic,
maybe a bit further East). These things make our lab Geiger counter
sound like an agitated rattlesnake. Then there is the nice little
’tanzanite’ week or so ago that turned out to be synthetic
forsterite…

Gem-A is the Gemmological Association, based in Hatton Garden (the
jewellery district) in London and it also runs the London Gem Testing
Laboratory. The Gem-A list is, at present anyway, limited to members
of that Association (International, with about half based in UK) and
is one of the benefits of Membership. This which is why we can’t
offer it freely to all interested parties. That said, I would love to
find areas where we can work with Orchid.

You might want to have a look at the Gem-A site -
http://www.gem-a.info - to get an idea of what we do. Or what we do
so far… My own background is as much the history of jewellery
materials and technology as gemmology. One of our publication Gems
and Jewellery (in association with the Society of Jewellery
Historians) is expanding its cover of historical jewellery technology
stuff, and our lab is widening its remit to also look the metals,
enamels etc (analysis, technology, toolmarks, authenticity). So if
you join Gem-A you will not only be able to be on the Gem-A List and
receive our publications, you will also be actively supporting
research into the history of jewellery technology. Sorry for the
sales pitch :slight_smile:

Gem-A USA has a booth at Tucson (AGTA - Booth 31) so I’ll be there
(and at the Orchid Dinner) and delighted to talk to any of you. If
you are interested in the history of jewellery technology and in
particular authenticating 18th - 19th century jewellery on the basis
of technology, I am giving a seminar on the subject at the National
Association of Jewelry Appraisers education conference on Thursday
3rd at the Clarion Hotel Tucson Airport - have a look at
http://www.najaappraisers.com/html/conferences.html

Best wishes to all
Jack Ogden
Dr Jack Ogden
Chief Executive Gem-A
T: +44 20 7404 3334


#8
What actually happens is the flux used to protect the stone during
the heat treatment melts and enters the cavity. This problem is
most often found in rubies but could be found in other gemstones as
well due to the process used. 

Well yes, that’s pretty much true as far as it goes, but the
treatment is not simply an unintended consequence of ordinary heat
treatment but, at least in the case of Mong Hsu ruby, a process
intentionally used to improve the appearence of lower qulity,
fracture filled stones. There is a detailed discussion by Richard
Hughes at:

Jerry in Kodiak


#9
Glass filled rubies are not the only new headache in our industry.
On my desk at the minute are samples of the green glass beads and
glass 'gems' that have supposedly been imported into the USA set
in 'tons' of costume jewellery - the pretty green is due to use of
depleted uranium. (Origin of the glass supposedly Czech Republic,
maybe a bit further East). These things make our lab Geiger
counter sound like an agitated rattlesnake.> 

Intriguing! Although I don’t deal much with precious stones or their
imitations (fonder of cheap cabs meself), I’m always on the lookout
for Czech pressed glass beads in a juicy, intense shade of
yellow-green - the hallmark of uranium glass. I bought a strand of
"Swedish fish"-shaped beads in this unmistakable color at a recent
bead show and have been meaning to take themover to the college lab
and Geiger them. (Don’t worry, I won’t wear them or chew on them or
store them next to unexposed film - I was just curious!)

Allegedly, this type of glass will also glow very brightly when
exposed to a blacklight. This might be a handier way for customers to
detect dangerous green glass, since not so many folks have Geiger
counters handy.

For a little more info on uranium glass, see

http://www.beadcats.com/radhaz.htm

Cheers,
Jessee Smith
www.silverspotstudio.com


#10

Very interesting reading for those who have to do with rubies.
http://tinyurl.com/38bzrq9

Cheers, Hans


#11

Hans,

Glad to see someone with your gravitas bringing up this subject, and
I would encourage everyone here to read this article. These "fakes"
are the elephant in the room, and if our industry doesn’t take
control of this monster, it just might squish all of us.

The ISG has been a leader in identifying this problem, and Robert
James has my personal thanks for his untiring efforts. He is
currently testifying in the class action suit against Direct Shopping
Network for their alleged undisclosed selling of diffusion treated
andesine. This isn’t an isolated problem - it’s systemic. (By the
way, I have absolutely no affiliation with the ISG, I’m just a fan.)

Macy’s should know better than to sell lead glass filled corundum as
"natural rubies." In my opinion it stinks, and woe to the jeweler
who takes a piece of this jewelry in for a repair - puts a torch to
it - and bang! It’s all over but the weeping.

Of course the short term profits are huge when you can buy lead
glass filled rubies for a buck a carat, and then sell them for
hundreds or even thousands per carat. But, what is the cost to the
industry in the long term? What happens when you show a real treasure
of a ruby to someone who then tells you they can buy the same thing
on the “web” for a few dollars…the argument that everyone is a
crook but “us” only goes so far.

Imitations, synthetics and lead filled stones all have their place,
but proper disclosure is paramount. That’s all the ISG and Mr. James
are asking for, and I don’t think that’s too much to ask. We’d all
better get a handle on this issue, or it will get it’s handle on us.
I never want to misrepresent anything, especially my work. Today I
find myself becoming more and more cynical. The short term profits
are just too great, and someone in the gem industry sales chain no
doubt sees that too. I’m constantly concerned about that one faceless
entity, that “one person,” who is willing to look the other way.
That’s all it takes, just one unscrupulous person, one doctored
stone, one needed sale, to wipe out years of building credibility and
trust.

Thanks for posting this Hans, I’m Glad you too are concerned.

Rgds…Ski & Cathy
Rocks to Gems


#12

Some good info concerning these litte devils. Our store is in the
Hampton Roads area of VA, with a huge Navy presence in Norfolk, VA.
We are seeing some really cheap, big & ugly glass filled rubies that
the service folks are bringing back from Afghanistan. Recently a
dealer came in with some very beautiful looking stones which he
identified as glass filled rubies. They looked very fine, again, very
inexpensive.

http://tinyurl.com/39ppmld


#13
Of course the short term profits are huge when you can buy lead
glass filled rubies for a buck a carat, and then sell them for
hundreds or even thousands per carat. But, what is the cost to the
industry in the long term? 

But we know the cost. The same happened in 97 with emerald
treatment. You could not give emerald away for several years after
that. Everybody should buckle up. It is going to be a rough ride.

Leonid Surpin
www.studioarete.com


#14

I had the DIS PLEASURE of working on one these for a jeweler friend
of mine. A simple prong repair turned into a near nightmare!! The
stone, of course, exploded! Luckily we could tell afterwards that
this stone was filled. It cost my buddy $1300.00 but now he looks
much closer at rubies! He bought it a couple of years ago and didn’t
think to check it closely. He learned! CHECK YOUR STONES PRIOR TO
REPAIRING ANYTHING! This is the one thing that needs to be repeated
constantly!!! Chips, cracks, abrasions, inclusions, bubbles, soap sud
inclusions, etc.

It will only save your butt in the long run!

Steve Cowan, Arista Designs