GEM ALLERT
Radioactive Cat's-Eye Gemstone
November 13, 1997
by:Jeffery Bergman
@Jeffery_Bergman
Photo: “Before and after treatment” courtesy of the Center for
Gemstone Testing
A frightning development in the never ending saga of gemstone
treatments came to light this last August. The story started out
innocent enough, but when the truth finally came out, a wave of
fear swept through the worldwide communiy of gemstone dealers.
Early in the month, two gem dealers based in Bangkok brought me
a small selection of 3 to 5 carat cat’s-eye chrysoberyls. Upon
first examination they looked like very fine quality natural gems
with sharp bright eyes and a very dark brown body color, but the
color was just a little different from any cat’s-eye chrysoberyl
I had ever seen before.
When I questioned the dealers, they said they had been told the
stones were heat treated. I was quite puzzled by this since I had
never read anything in any gemological literature about any
treatment processes for any of the chrysoberyl family. I checked
Kurt Nassaus diffinative work “Gemstone Enhancement” as well as
the GIA chart on detecting gemstone enhancements and found
nothing.
What I heard next made me begin to question the literature I had
just reviewed. The dealers said they had sold these cat’s-eyes to
an Indonesian dealer a month earlier for a few hundred dollars
per carat. Then, a few weeks later, they bought their gems back
from the very same dealer for over $1,000 per carat.
Why would any gem dealer in their right mind do something like
this? Simple. When they sold the cat’s-eyes, they were a pale
miky yellow color. When they bought their gems back they were a
much more valuable chocolate brown color. Having known these
dealers well for over a decade, I was confident in the veracity
of their story.
Gem labs are the super sleuths, the Sherlock Holmes’s, the
detectives of the gemstone industry. One of the best labs in the
world just happens to be around the corner from my office, so I
borrowed one of the suspect cat’s-eyes, dropped it in my pocket,
and headed for the Asian Institute of Gemological Sciences (now
the Center for Gemstone Testing). I gave them the stone, a 3.5
carat oval, and briefed them on the story.
I then set off on my own search to discover the secret of this
new treatment process. My dealer friends said the cat’s-eyes came
from the Orissa gem deposits in India, so I obtained a dozen
small samples from this source, and began a series of heat
treatment experiments attempting to duplicate the results I had
seen. Every variation of temperature, time and atmosphere
produced not the slightest change in any of the samples. This
failure lead me to believe we were not dealing with a heat
treatment process.
My daily phone calls to the lab all resulted in the same news,
“We can not find anything”. I went back to the dealers and began
to ask more questions. During one conversation, one of the
dealers inquired, “Is it possible to get sick from wearing one of
these cat’s-eyes in jewelry?”. The implications hit me like a ton
of bricks.
I called the lab that was checking the sample and got Gary
Dutoit on the line. I asked him if a residual radiation check had
been done on the stone and he said “No. Hold on and I’ll go get
it”. He came back on the line shortly and said “listen to this”.
With a Geiger counter on audio, he placed the stone near the
machine, and over the phone line I heard the tell tale “Beep
beep beep beep beepbeepbeepbeeeeeeeeeeeeeeeeee…” as
the counter went off the scale. Gary quickly found a lead
container to safely store the very hot gemstone.
Preliminary testing, using equipment provided by Doug Parsons of
Beta Color Ltd., verified the stone was indeed highly radioactive
and quite dangerous. I shudder when I think of the time I carried
it around in my pocket. The 3.5 carat sample revealed a
radioactivity level of 52 nCi/g. This is significantly higher
than the legal release levels set by the relevant authorities in
the USA (1.0 nCi/g) the UK (2.7 nCi/g) and Asia (2.0 nCi/g).
Subsequent tests by Beta Color have shown it to have a moderately
long half-life of approximately one-hundred three (103) days,
indicating that this particular stone will reach the legal
release level in Asia in another sixteen (16) months (around
January 1999). Before that time it must be kept in a properly
shielded radioactive materials storage container.
Meetings with lab director Ken Scarratt, and three of the
dealers involved, revealed that several hundered carats of this
treated material was already circulating through the gem market
in Thailand. Further meetings determined that significent
quantities were also on the market in Indonesia, where it is
believed the nuclear facility responsible for the treatment is
illegally releasing the dangerous gems “out the back door”. At
this point we had to assume the treated cat’s-eyes were also
making their way into other Asian markets. It was not long before
our fears were confirmed.
On September 2, I left for the Hong Kong Show to help out fellow
gem dealer Dan McKinney in his booth. Since he processes and
sells blue topaz he has a Geiger counter in his office to check
for radioactive stones that have been released before they are
safe. I visited several prominant cat’s-eye dealer’s booth’s and
told them the story, offering to check their stones. Fortunately,
all of their stocks were non radioactive.
Word traveled fast, and dealers began to drop by the McKinney
International booth to have their cat’s-eyes checked for
radiation. Every stone we checked was fine, until one dealer
visited us just a few hours before the end of the show. He had a
beautiful gem of over 30 carats in a gold mounting surrounded by
diamonds. It was so radioactive that the Geiger counter went off
the scale.
Finding a dangerous cat’s-eye in Hong Kong, already mounted in
jewelery, shows just how far these gems have been dispersed in
the Asian marketplace. Although Ken Scarratt, president of the
new Center for Gemstone Testing in Bangkok, has alerted the
proper international nuclear authorities about the problem, it is
really the gemstone industries responsibility to police itself.
Unfortunately, radioactivity can not be seen, felt, heard,
tasted or smelled, but it can be extremely dangerous. Anyone
subjected to close contact with these gemstones runs a high risk
of developing serious health problems, with cancer at the top of
the list. If you suspect you may have treated cat’s-eyes in your
inventory, the only safe and sane thing to do is to have them
checked in a lab equipped with a Geiger counter. If they are
found to be radioactive, they must be stored in a proper storage
container until they reach levels safe and legal for release.
END
Jeffery Bergman has been involved in the international gemstone
trade for over 25 years, and was an AGTA member for 10 years. He
can be contacted at:
Gem Source
CS Building, Suite 502
35 Surasak Road, Silom
Bangkok 10500 Thailand
Ph: (662) 238-2033 & 34
Fax: (662) 238-2044
E-mail: @Jeffery_Bergman