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Gemmological Commission
Gemmological Commission to explore ways
to improve gem harmonisation and consistency
By Hanco Zwaan, President
CIBJO Gemmological Commission
T
he CIBJO Gemmological Commission (CGC)
serves as a platform for gemmological
laboratories to raise issues or formulate
recommendations, specifically from a technical
point of view. These can be considered by other
commissions when discussing the Diamond,
Pearl and or Gemstone Blue Books. In short,
technical updates help to clarify the current
situation and support harmonisation.
In this respect, during the last congress in Tel
Aviv, the CGC presented its recommendations to
the Coloured Stone Commission to edit Annex
A of the Gemstone Blue Book, adding cases
of irradiated quartz, and also making sure
CIBJO SPECIAL REPORT 2014
GEMMOLOGICAL COMMISSION
PAGE 1
that all statements regarding the irradiation of
gemstones are correct.
In addition, the impregnation declarations of
opal and turquoise were corrected and included.
After thorough discussion, most of the edits were
agreed upon and, after being presented, were
approved during the Coloured Stone Commission
meeting.
CONSISTENCY AND RELIABILITY
In view of concerns that have been raised
about inconsistencies in results presented by
laboratories, we have explored how laboratories
worldwide could work together and harmonise
with the trade, to improve consistency, reliability
of information and consumer confidence.
Closer cooperation between the labs is needed
to fight disharmony, because inconsistencies
occur in both nomenclature and the reporting
of results, for instance in the areas of origin and
determination of treatments.
Closer cooperation is called for, but it is not
necessarily easy. The experience of major
and important laboratories that work together
under the umbrella of the Laboratory Manual
Harmonization Committee (LMHC), and which
are also represented in the CGC, show that it is
a monstrous task to get only seven laboratories
together, let alone even more institutions
worldwide.
But the fact remains that these laboratories
have succeeded in sitting down together on
a regular basis, and as a consequence have
made considerable progress in harmonizing
gemmological
report
nomenclature.
They
have produced numerous information sheets
with valuable information on various coloured
gemstones and treatments, providing alternative
options when considering nomenclature on gem
reports.
These sheets can be accessed on the Internet
at
http://www.lmhc-gemology.org/LMHC_
Information_sheets.html. They give a clear
picture of the type of information that can be
found on a gem lab report, and on the generally
accepted nomenclature.
LMHC has always been and will continue to be
open to suggestions and comments from other
labs and the trade. In this way, it truly serves
as a platform for harmonising nomenclature
even more. However, it was agreed though that
CIBJO should examine what more can be done to
improve the situation.
To advance the process, laboratories around
the world should take note of the information
sheets produced by LMHC and consider what
nomenclature they can comply with and implement
in their own organisations. This would be a first
important step, as this would also be very much in
line with what has been laid out in the CIBJO Blue
Books. In addition, CGC will continue contributing
to harmonisation by providing factual information
through presentations on relevant topics.
Pornsawat Wathanakul, Vice President of CIBJO’s
Gemmological Commission.
Claudio Milisenda, Vice President of CIBJO’s
Gemmological Commission.
Hanco Zwaan, President of CIBJO’s Gemmological Commission.
CIBJO SPECIAL REPORT 2014
GEMMOLOGICAL COMMISSION
PAGE 2
Opal and hydrophane. Nomenclature and criteria to distinguish them will be discussed at the CIBJO
Congress in Moscow. (Photos: Netherlands Gemmological Laboratory)
SCOPE OF THE CGC AGENDA
Although members of the CGC have already given
their input on harmonising the diamond, gemstone
and pearl book, this topic will be dealt with in the
other commissions and sectors at the upcoming
CIBJO Congress. Improving consistency between
laboratories, the reliability of information and
consumer confidence will again be on the agenda
of the next congress in Moscow. We will have
discussions on the use of the information already
available, the status of statements on country of
origin that are made on laboratory reports, and the
industry and public needs in this area.
We will also talk about the use of colour descriptive
terms, such as “pigeon blood red,” “royal blue,” and
so on. It seems that there is a strong demand to
Sapphire with a medium-dark, vivid blue colour,
which may be considered ‘royal blue’ in the
trade. (Photo: Netherlands Gemmological Laboratory)
CIBJO SPECIAL REPORT 2014
GEMMOLOGICAL COMMISSION
PAGE 3
use these terms on gem reports. We will need to
consider when we really want these terms, and,
if so, is there a way to agree on what objective
colour descriptions compare with those terms?
The CGC will also discuss the description of
opal and hydrophane. At the last Gemstone
Industry and Laboratory Conference (GILC) in
Tucson, Arizona, the “opal-hydrophane problem”
was discussed again. During this meeting
it became apparent, especially in Australia,
that hydrophane needs a proper description
to distinguish it from stable precious opal.
Advice is needed on nomenclature, and on the
criteria required to make a distinction between
hydrophane and opal.
It is important that laboratories harmonise on
an approach to deal with the opal-hydrophane
problem and on relevant nomenclature. A short
update will be given on the progress LMHC has
made on this subject.
At the 2014 CIBJO Congress in Moscow, the
Gemmological Commission Steering Committee
(GCSC) will hold its pre-congress meeting on
Sunday, May 18, from 09:00 to 10:30 a.m. The
Gemmological Commission meeting will take
place on Tuesday, May 20, from 15:15 to 16:15.
Both meetings will be chaired by CGC President
Hanco Zwaan, of the Netherlands, who will be
assisted by two Vice Presidents, Pornsawat
Wathanakul of Thailand and Claudio Milisenda
of Germany, who is replacing Kenneth Scarratt.
Many thanks are extended to Ken for his five
year tenure as Vice President of the commission.
ALL RIGHTS RESERVED
© CIBJO, The World Jewellery Confederation 2014
www.cibjo.org

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