THE MILLENIUM CUT by ROGERIO GRACA
Have you ever heard of a gemstone with one thousand facets?
As a gem cutter, I have never heard of a gemstone with more than three hundred facets, let alone one thousand. One of the most popular cuts, "the brilliant cut", displays fifty-eight facets, so it is hard to believe that a single stone could have one thousand facets. Actually, I had never even considered cutting a stone with more than two hundred and fifty facets. The amount of time required to cut such as stone is tremendous, as well, the beauty of a gemstone is not necessarily enhanced by more facets.
"A stone with one thousand facets might need to be touched by the diamond grinding wheel (diamond lap) between five thousand to over ten thousand times"
I calculated the arrangement of facets without any trouble, but transporting it from a piece of paper to a piece of rough stone wasn't quite that simple.
One of the main challenges wasn't just fitting one thousand facets on a piece of rough that was not much bigger than a fingernail, rather, it was to maintain the degree of sharpness between the facets due to their size and the small difference in angles between them. To solve this problem I adopted an extremely hard-surface polishing lap (ceramic lap) to minimize the possibility of rounding off the facets' edges.
My next consideration was to select an appropriate piece of rough for such a time consuming project. I chose a citrine that was clean enough and large enough to be worth the effort.
The third challenge was related to the design. I had to take into account the fact that the number of facets contained on the rows close to the culet (bottom of stone) had to fit into a much smaller space than the rows surrounding the widest part of the stone (girdle). Because the original figures of the design presented forty-eight facets for each row, I had to cut the number in half bringing it to twenty-four facets for the last few rows. Furthermore, in reference to the design, I had to make sure that the number of facets in each row were compatible (divisible) with the machine index used (96 positions) for cutting the stone. Forty-eight facets on each row and twenty-four facets for the last four rows, totalling six hundred and twenty-four facets on the bottom alone.Theoretically, I couldn't see why it wouldn't be possible to cut a stone with that amount of facets.
There was another factor not to be overlooked. How could I find out beforehand the proper depth of the rough material in order to safely accommodate 624 facets on the bottom in addition to 376 facets on the top? It seemed obvious to me that the piece of rough would have to be somewhat deep and bulky to accommodate one thousand facets: as a result weight retention would be inevitable. What I really had to determine was how much space was available and how important it would be to cut the last rows close to the garnet's refractive index (approximately 39 degrees).
Considering the number of facets involved and the uniqueness of each material, I decided to focus primarily on having enough space to accommodate one thousand facets rather than focusing on finishing each stone with the correct refractive index. The outcome would be an exaggeration of the "Portuguese cut", a stone with hundreds of facets precisely cut, but still with the look of a stone cut in an older method. The reason for this look lies in the very gradual change of angles from top to bottom, giving the stone a warmer look, rather than a "cold look" created by sharp edges as in the brilliant cut. This combination, "the old cut" with a very prominent belly on the bottom performed by a precision cutting machine turned out to be a good expression of the past and present, brought together to symbolize the millennium and a state of balance.
Assuming that no major mistakes occurred during the creation of the stone, one question remained. How many times did the stone have to be touched from the first to the thousandth facet? Can you make a guess? I'll give you a hint. Three different laps: a coarse lap, a fine lap, and finally a polishing lap had to be used in sequence for every single facet. If your guess was 1000 x 3 = 3000 times, you were too conservative. I wish that I had only needed to touch each facet once for each cutting/polishing stone, but the fact of the matter is that each facet has to be touched from one to four times either during cutting or especially polishing.
Taking that into account, a more accurate figure would be:
1st lap (coarse lap) 1000 x
2nd lap (fine lap)2000 - 4000 x
3rd lap (polishing lap) 3000 - 5000 x
Based on this, you can assume that a stone with one thousand facets might be touched between six thousand to over ten thousand times depending on the cutter's methodology and skills.
In addition to the idea of creating a unique stone, there was another reason that encouraged me to cut a stone with one thousand facets. This relates to the fact that few cutters in the world work with the precision cutting machine, the only equipment able to meet the high degree of accuracy required for this particular design. Therefore, the possibility of the Millennium cut being largely reproduced is eliminated. Another deterring factor in its reproduction is the time involved and the design particulars.
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