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Grading the Colorful, The Rocky Road to Quality Assessment


#1

"Collectors Universe has stated it has every intention of becoming
the world’s leading purveyor of diamond and colored stone
pedigrees—“maybe not tomorrow, or next year,” (CU President) Haynes
says, “but within the foreseeable future.”

David Federman, Professional Jeweler, 2006

At the beginning of a new year it is traditional to assess the past
year, make resolutions and talk about the future. Several happenings
over the past twelve months that considered in isolation are
important taken as a whole appear to be crucial milestones along the
road toward colored gemstone quality grading.

A consortium of seven major gem laboratories under the aegis of the
Laboratory Manual Harmonization Committee (LMHC) established
important precedents:

  1. First, they abandoned the traditional protocol of naming a gem
    based on species and variety. The committee agreed that on grading
    reports issued by member labs to use the term “Paraiba” to describe
    all copper colored or cuprian tourmalines regardless of their actual
    source.

  2. In a separate decision, the LMHC also decided to stray beyond the
    realm of verifiable science and enter the world of aesthetics. They
    agreed to adopt a set of color parameters for and use the term
    "Padparadscha" sapphire on grading reports issued by member labs.

This year a new player entered the grading games: /Collectors
Universe (CU)/, a publicly traded company that provides certification
for coins stamps and guess what, baseball cards purchased /American
Gemological Laboratories/ (AGL) the only major U. S. lab that issues
quality grading reports on colored CU has the financial
muscle and appears poised for an strategic play: The company already
owns /Gem Certification and Assurance Lab/ (GCAL) as well as
/Gemprint/, the diamond identification and registration system that
will laser print an ID # on

In order to have a universal colored stone grading system you must
have a universally acceptable methodology. Internet shoppers, in
particular, are demanding a way to compare apples to apples and what
the market requires the market sooner of later gets. Getting all
major players to accept a single methodology may be difficult but a
broad basis of agreement between a number of important labs may do
the trick. The LMHC includes seven of the world’s most respected
gemological laboratories: (AGTA Gem Testing Center, CISGEM (Milan),
GAAJ (Japan), GIA (USA), Gemological Institute of Thailand, Gbelin
Gem Lab (Switzerland) and SSEF Swiss Gemmological Institute
(Switzerland) missing only AGL and The Swiss Lab Bangkok (GRS) the
very well respected Bangkok based lab run by Adolph Piretti.

Historically, no institution, not even the mighty /Gemological
Institute of America/ (GIA), the originator of the universally
accepted diamond grading system, has succeeded in creating an
acceptable colored stone grading system. GIA tried twice, first in
the 80s /Colormaster/, a sort of color blender and then with
/Gemset/, a set of round faceted plastic doohickeys, both of which
were flawed and failed to win industry wide acceptance. GIA has
wisely abandoned its go it alone strategy and joined LMHC.

Instrument based color determination appears to be the wave of the
future. According to American Gemological Laboratories C. R. "Cap"
Beasley “instrument based measurement is simply more consistent”.
The fact is; you have the rock, the light and the observer,
standardize the latter two and you are eliminate two variables. Does
Beasley have an instrument? None that he will admit to.

AGL is still the only major laboratory that grades colored
Beasley introduced his own system, /Colorscan/, in the
early 1980s, a system that many gemologists including this writer
believes was the most viable system yet created. /Colorscan/,
however, relied on the human eye as observer. New Computer based
systems such as /Gem-e-Square /that project a range of
hue/saturation/tone on a color computer monitor also require the
human eye and judgment to make a call.

Collectors Universe appears to be making a bid to become a major
player in quality grading. I will be interviewing CU president Bill
Haynes, later in the week. Stay tuned.

*Contest: *

*The Hope Diamond, * *Inflation in the Seventeenth Century *

*Take a shot, win a signed copy of */Secrets Of The Gem Trade, The
Connoisseur’s Guide
/

In 1669 Louis XIV of France purchased the /French Blue/ diamond from
the famous gem merchant Jean-Baptiste Tavernier for 220,000 livres or
42.7 million dollars (1 livre = $1,941.). In an inventory taken by
the French crown in 1691 the /Sancy /Diamond, a colorless stone of
55.23 carats and the largest white diamond in Europe at that time,
was valued at 24.2 million dollars.

By the time this inventory was taken, The /French Blue/, had been
recut by M. Pitau to 69 carats, a 40% loss in weight. Despite this
the stone that ultimately became the Hope Diamond, was valued
at…in 1691? The person who comes closes wins a signed paperback
copy of /Secrets Of The Gem Trade/. Post your answer in French
/livres/ and your email address to the *Comments *section of the
blog. Winner’s name to be posted on GemWise in two weeks. Hint: read
Ronald, /The Sancy Blood Diamond/, Morel, /The French Crown Jewels/.