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Their interest in
collaborating with me varies. They all agree that there is a lot of
misinformation in the public domain, and many want to set the record
straight and educate the public in accordance with their
charters. Others see an opportunity for research to be performed on a pet project
with little
expense to them. These many years have yielded a rewarding collaborative
effort to the mutual benefit of all.
Research Process
My original research
began circa 1980. My research process at that time involved locating
photographs or line drawings of the stone to be replicated. This process
was slow and tedious since computers were somewhat of a rarity and had
very limited capability. The Internet as we know it today did not exist,
and only universities were engaged in regular e-mail correspondence.
This limitation meant that one round-trip of correspondence with an
authoritative source could take weeks.
Once suitable documentation was found, I would apply tracing paper over
the photo or drawing, and then painstakingly transfer the facet pattern
of the crown and pavilion to the paper. I then used trigonometry to
analyze the facet pattern and to calculate the angle and index setting
for each facet (all this, of course, tempered by seven years of
stone-cutter’s judgment). Each step had its inaccuracies, so the final
stone was a close approximation of reality. Certainly good enough for
display, but more of a
representation than a true replica.
Fast forward 25 years ...
Today, computers
have more computing power, e-mail and instant messaging allow
near-instantaneous, near-simultaneous worldwide communications, and
highly accurate modeling and graphics programs abound. References are no
longer restricted to documents at the local library, but can be
purchased over the Internet or borrowed through inter-library
loans. Communication and coordination with museum curators, professional
cutters, and others are increased by orders of magnitude. Progress made
in all these factors now enables much more accurate replicas to be
created.
The discoveries made today would not have been possible even five years
ago. Technology (such as the programs used to
model the Hope diamond)
had not progressed
far enough. The
researchers of the past (including me!) shouldn’t be faulted as they did
the best they could with what they had, but some information does need
to be corrected.
Today, my
research process
starts much as it always has, by locating pictures or drawings of the
stone to be replicated. (In some rare cases, I have been granted direct
access to the original stone.) In all cases, a photograph is preferred
over a line drawing, as drawings are subject to artist interpretation. A
photo captures the stone objectively, it only records what the camera
sees.
Although photos can present minor inaccuracies due to parallax,
spheroidicity of the lens, and other optical errors, they are currently
the most accurate representation of reality. Parallax is potentially the
most serious error, but professional photographers realize this, and it
is assumed that this problem is considered by the professional
photographer when provided a once-in-a-lifetime opportunity to capture
one of these phenomenal diamonds.
Only after the best raw data has been obtained and analyzed, the
photograph (or drawing) is converted into a digital format and magnified
anywhere from 3 to 30X. Line drawings of the pavilion and crown are then
drawn. Lines are drawn at the edge of each facet with to-the-pixel
accuracy until the full pattern materializes. Unfortunately, in many
photos lines can be very indistinct. In these instances, stonecutter
judgment, tempered by knowledge of ancient cutting techniques and
cultural preferences, fills in these areas.
Size, shape, and facet pattern must be accurately determined. This is no
small feat, even though it could be reasonably be expected that these
are all documented for any world famous diamond. Wrong! Not even the
Royal Collections, Tower of London, or even the Queen of England had
the dimensions
of the Cullinan's. The Blue Heart, residing in the Smithsonian for
almost 50 years, has been weighed, but its dimensions have never been
published, and as of this writing (September 2006), are unknown even to
the Smithsonian (this is soon to be corrected). There
is only one place I’ve been able to find the dimensions of the
Cullinan III-IX diamonds: The Asscher diaries in the back of Balfour’s
book.
The derived and calculated line drawings are then used to virtually
“cut” the stone via a computer program called GemCad (www.gemcad.com).
This program not only allows for determining the cutting angle and
setting for each facet, but also it permits the cutter to become
familiar with the actual cutting process.
Interrelationships between facets, cutting sequence, and similar issues
are discovered. This "virtual testing ground" is extremely important, as
learning these on a piece of rough is not only time-consuming, but also
expensive when dealing with these larger diamond sizes. Although cubic
zirconia is relatively cheap, destroying a 2,000-carat piece of rough
unnecessarily involves a cost in money, time, and wear and tear on
equipment (and the stone-cutter!) that should be avoided.
Cutting a stone on the computer is a highly iterative process that can
be very tedious when absolute precision is required. The simplest of
diamond cuts, the standard brilliant, has 57 facets placed in a regular
pattern, and each has its own angle and index setting. Fifty seven
facets with two variable each, and you are simultaneously solving for 114 variables. (This is somewhat of an exaggeration. For symmetrical
patterns, the variability is considerably reduced.) Try solving this
for an irregular pattern such as the 186 carat version of the
Koh-I-Noor, irregularly shaped with over 200 facets, and it becomes
quite a chore to duplicate. A slight variation on one facet affects all
its neighbors, which affects all their neighbors, so a change on one
facet affects the entire stone. It is not an easy process to juggle all
the variables, which is why this phase can easily take 50-100 hours for
a moderate-to-difficult facet pattern. And this is time invested before
the rough even touches the machine.
Once the GemCad file is created, it is imported into a document
containing the cutting instructions, dimensions, and life-size drawings
of the stone from all angles. This document serves as the reference for
the cutting process.
For my own replicas, I do the cutting
using a very old
Ultra-Tec faceting machine and standard processes. A 20X optical
comparator is used to ensure dimensions of individual facets on the
stone match those in the line drawings. On facets larger than about 10
mm, a digital caliper accurate to 0.01 mm, and a table gauge accurate to
0.1 mm, are used. Digital calipers are readily available from almost
any tool department, and the table gauge can be ordered from the
Gemolgical Institute of America (GIA). These three items, or tools with
similar capabilities, are absolutely critical in creating accurate
replicas.
As good as GemCad is (and it is outstanding for this purpose), it still
has its limitations. For example, it is difficult to transfer the
outline of the stone in the diagram to the computer model, especially if
the girdle is ground and not faceted. Also, any derived angles and
settings still need to be tempered by stone-cutter judgment. And this is
where science yields to art. There are, for example, nuances of the
cutting process, such as stone-centering, over- and undercutting,
stonecutter technique, and limitations of the faceting equipment, that
can alter the calculated values. Many famous diamonds were not cut for
symmetry, especially the historic Indian stones, which greatly increases
the difficulty of creating an accurate replica using this or any other
"rules based" program.
As I mentioned earlier, there have been
some extremely rare cases where the research presented here on this Web
site was performed on the real stone. This was the case deriving the
data on the Hope diamond as a result of a
Discovery Channel program. In the case
of the 186-carat version of the Koh-I-Noor diamond, Coster Diamonds in
Amsterdam loaned me one of their two glass models made circa 1851. And
one of the two plaster casts made of the stone in 1851 was borrowed from
the Natural History Museum in London and was studied over a period of
four months. These research techniques were preferable to using the
numerous line drawings of this stone, for whose version would be used?
Bauer's, Dieulafait's, or someone else's?
The research for
the diamonds presented on this site is exhaustively meticulous. It
should go without saying that the data presented here result from the
cooperation of many individuals and organizations
that share the common goal of publishing accurate scientific
knowledge. These individuals and organizations cannot be thanked enough
for their support, and hopefully all their efforts have been properly
acknowledged.
One Last Note ...
There are many critics out there who
believe that the
information presented in this Web site contradicts what they’ve heard or read. There are others
who just wonder, “Where did this information come
from?” The research process and methodology for each stone is given and
laid bare for scrutiny, and hopefully, you will agree with the process used
to reach the final conclusion. In no way
should the research be interpreted as “I am right, you are wrong.” As
in all science, two researchers can be presented with the same
information, yet arrive at different conclusions. The information is
presented, and you can draw your own conclusions. With any luck, your
future research will uncover some other undisclosed fact, and then this
can be added to the current body of knowledge. |
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