Given the special characteristics
of the emerald, the presence of fissures, flaws or impurities, there
is a constant search for new processes that might yield better and
more satisfactory cleaning and beautification methods for the stone.
One of the most common and currently accepted methods is to use
acid to clean the stones. After the material is acid-cleaned it
is left in long enough to reach neutralization and is then given a thorough acid
wash out. After clean up, the stones are treated in our state of
the
art laboratory with cedar oil or Permasafe. To improve durability
of the stone we use Permasafe enhancement from
CGIE, a wide world accepted treatment.
Our company uses the
basic standard of emerald enhancements of ICONTEC (Colombian Institute
of Technical Law and Certification). This standard is GTC 46 approved
from 11/26/1997, for the Colombian National Council of industrial
procedures.
Cedar Wood Oil: Oil distilled from the leaves of the "Juniper's Virginian".
It is a colorless liquid dissolved in alcohol.
Specific Gravity: 0.94 y 0.98
Refractive index: (20°C) 1.50 and 1.52
PermaSafe (NEW): To improve the durability of emerald enhancements
and to reestablish market confidence among wholesalers, dealers
and customers, our company uses only the new emerald filler named PermaSafe from CGIE.
PermaSafe is a durable
epoxy resin and can withstand ultrasonic cleaners and the
heat of a cutting wheel. PermaSafe reportedly can be removed from
the emerald and fluoresces a pale blue in long wave ultraviolet
light for easy identification. PermaSafe is touted to be transparent
and closer to emerald's refractive index, thereby concealing fissures
more effectively. It is also less viscous and can permeate emeralds
with a minimum of heat and pressure.
The text below about
permasafe is taken from an article, dated April 1999, on the professional
Jeweler web site.
New Emerald Treatment at the Source
A Colombian company tackles the problem of filler durability with
PermaSafe Not everyone accepts the gloom enveloping the emerald
business. In Bogotá, Colombia, the world's most important
emerald source, C.I. Gemtech Ltd. has taken a proactive approach.
"PermaSafe," a new durable emerald enhancement, is the
product of a partnership Gemtech forged with a gemological laboratory,
the Center for Gemological Studies of Emerald, Bogotá. The
lab's director, Rodrigo Giraldo, a graduate gemologist, says PermaSafe
offers durability and safety. "And that goes to the heart of
the problem with emeralds," says Gemtech President Jaime Rotlewicz
Cohen.
Many gem dealers agree with Rotlewicz. They say improving the durability
of emerald enhancements and explaining to buyers what exactly is
in an emerald will go a long way toward reestablishing market confidence.
What Is It?
PermaSafe is an epoxy resin, similar in some ways to the secret
material used in the Arthur Groom-Gematrat enhancement (Professional
Jeweler,April 1998, p. 50), Giraldo says. Both treatments are durable
and can withstand ultrasonic cleaners and the heat of a cutting
wheel, he says. PermaSafe reportedly can be removed from the emerald
and fluoresces a pale blue in long wave ultraviolet light for easy
identification.
PermaSafe is touted to be transparent and closer to emerald's refractive
index, thereby concealing fissures more effectively. "It is
also less viscous and can permeate emeralds with a minimum of heat
and pressure," says Giraldo. Arthur Groom of Arthur Groom-Gematrat,
New York City, says there probably are more differences than similarities
with his product. Nevertheless, Groom welcomes the development of
PermaSafe. "It is a positive development because in Colombia,
they are beginning to understand the importance of durability in
emerald enhancements," he says. Another U.S. emerald dealer
agrees. "It seems to be pretty stable," says Ray Zajicek
of Equatorian Imports, Dallas, TX. "I've run several durability
experiments on emeralds treated with PermaSafe and am positive about
the results." Gemtech and its lab say they've sent samples
of the new treatment to all of the world's major laboratories. In
the U.S., the Gemological Institute of America Gem Trade Laboratory
in Carlsbad, CA, and the American Gem Trade Association Laboratory,
New York City, confirmed having received samples for study. (GIA
expects to release the first part of a report about a wide variety
of emerald fillers in an upcoming issue of Gems & Gemology,
its quarterly journal).
- by Robert Weldon, G.G.