Treatments:
If you are not a gem or jewelry enthusiast,
you may be surprised to learn that many gemstones are enhanced
in some way or another. From diamonds, rubies, sapphires,
and on down to 'lesser' stones, treatments are
quite common. The types of treatments and the reasons for
treating a stone are very dependent on the classification
of the stone. Some estimates suggest up to 95-99% of all
emeralds are treated. Most are treated to improve the passage
of light within stone. The physical makeup of the emerald
crystal, with its tiny natural fissures simply makes it
logical to do so. As is the case with most gems, the stone's
natural properties simply dictate which enhancements are
acceptable and which are not. A perfect example of this
would be the heat treatment of tanzanite. Before heating,
tanzanite is a brownish color, but turns a permanent blue
or purple color after heating. The enhancement method is
accepted because no foreign coloring agents were introduced,
the method is common practice, and it is generally fully
disclosed to the buyer.
Cedar Wood Oil
Many centuries ago, the Greeks began using colorless oils
to improve the appearance of emeralds taken from Egypt.
The oil would fill in the natural cracks and fissures within
the stone improving how light may pass through the stone.
The practice is still extremely common today. In fact, it
is the most widely practiced and accepted method of emerald
enhancement. Today, mostly natural, colorless cedar wood
oil is used and has been for the past four decades. It is
not permanent, but it is rather stable. Over time, some
oil may gradually evaporate or 'leak' from the
stone. When this happens to lightly oiled stones, the change
in appearance will not be significant or even noticeable,
but may be on those that are more heavily treated. Keep
in mind that we are not talking about months or even a few
years, but likely over a decade or more. Ultrasonic jewelry
cleaners and harsh solvents will also remove cedar oil treatments
and perhaps other types of treatments as well. These cleaners
should never be used on emeralds. If a stone loses its oil
enhancement, most can be retreated. Most of the emeralds
sold by Embassy Emeralds have been lightly treated with
cedarwood oil.
Epoxy
There are many types of epoxy treatments; therefore we will
speak of them in a rather general sense. They are as varied
as the emeralds they're applied to, and, of course,
some are better than others. Epoxies are used to fill naturally,
as well as unnaturally, occurring cracks and fissures in
stones. They are used far less than cedar oil treatment
and are considered a less desirable treatment option. The
practice of using an epoxy is accepted to an extent. When
done properly, the treatment can greatly improve the appearance
and transparency of a stone. Some can be used to deceive
the buyer..so you need to be aware of what's
out there. From Embassy Emeralds you have little to worry
about. Our sources are established and reputable. We feel
very comfortable offering the stones we do because we know
our sources share the same high quality standards that we
do.
Gematrat
Gematrat was developed in 1997 as a way to permanently treat
emeralds, leaving them in a stable and permanent state once
finished. The process has been defined as 'gemstone
branding' and begins with a very extensive cleaning
of the stone which may take weeks or even months in some
cases. The stone's tiny fissures and cracks are then
filled with the colorless Gematrat substance, which is said
not to leak or discolor. The substance also contains a tracer
which glows blue under ultraviolet light.
According to the producers of the treatment,
you can put Gematrat treated gems in an ultrasonic cleaner,
a steamer, and even recut the stone without damage. The
stones are marketed with an American Gemological Laboratories
(AGL) report.
ExCel
Another emerald treatment process developed after the Gematrat
process. This process does not include the tracer element
that was present in the previous process because of incompatibilities
with the treatment and the appearance of many fakes that
mimicked the tracer's effect under ultraviolet light.
Information about the gem is laser engraved on the girdle
of the stone.
Palm Resin
Also known as Palma, this is a type of oil-like plastic
treatment that is used in place of cedarwood oil. The treatment
is not stable or permanent and tends to leave a milky-white
residue. It is still used, but it is not considered an acceptable
treatment.
Opticon
A plastic treatment that first appeared in Brazilian emeralds
in the 1980's. The use of this treatment was not disclosed
and was considered an unethical method of enhancement. The
Opticon substance is green colored, but may turn yellowish
over time. Many feel that Opticon treated emeralds are easily
detected by their appearance when compared with typical
untreated or cedarwood treated stones.
PermaSafe
This permanent, synthetic epoxy resin emerald treatment
was developed by the Centro Gemologico para la Investigación
de la Esmeralda (CGIE) in Bogota, Colombia. (Gemology Center
for Emerald Investigation) The treatment was intended to
be a Colombian alternative to the Gematrat and ExCel permanent
treatments. It is reportedly a stable, permanent treatment
that will not evaporate or leak and can safely be subjected
to ultrasonic cleaning. The same resin has been used in
other commercial applications outside of the jewelry industry.
Joban
A treatment commonly used in India that uses a green oil
to not only fill and mask the cracks and fissures in the
stone, but to also give it better color. The process is
considered unethical.
Paraffin
Commonly used on African emeralds, paraffin is used in an
oil or wax form.
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