 |
| The 12-carat Blue Moon. Photo credit: Cora International/Tino Hammid |
A little over a year ago I was invited to view a 12-carat blue diamond, known as the “Blue Moon” prior to its only public exhibition at the Natural History Museum of Los Angeles County.
Suzette Gomes, CEO of Cora International, a manufacturer of diamonds and jewels known for working with statement diamonds, showed the gem on a plain gray tray under office lighting. When asked of its value, she became annoyed barking the word “priceless” a couple times.
Well it turns out that priceless has a price as it will go up for auction at Sotheby’s with an estimate of $35 to $55 million. Any successful bid at the high end of this estimate will shatter the record for a blue diamond, which is $32.6 million paid in November 2014 in Sotheby’s New York for a pear-shaped 9.75-carat rare Fancy Vivid Blue Diamond Pendant owned by Bunny Mellon.
For Gomes and Cora International, it will present what should be a healthy profit for the 29.62-carat rough it purchased for a reported $26 million even after the costs—which include cutting and polishing it into the 12-carat Blue Moon (which took three months, according to Sotheby’s, after five months of study), exhibiting and travel fees and auction commissions.
There are very few people in the world with the means and desire to purchase such a diamond so Sotheby’s has no doubt been in contact with them and must be fairly certain that the gem, now set on a ring, will meet its estimate—and perhaps surpass it. It is obviously the top lot of its November 11 Magnificent Jewels & Noble Jewels sale in Geneva.
 |
| The Blue Moon presented to the press at Sotheby's London in September. Photo credit: Sotheby's |
So, what the makes the Blue Moon so valuable?
First, it’s size. At 12.03 carats, it is the largest cushion-shaped Fancy Vivid Blue diamond ever to appear at auction.
Second, its report from the Gemological Institute of America. The organization graded the gem as Internally Flawless and Fancy Vivid Blue, the latter being the highest possible GIA grade, David Bennett Sotheby’s International Jewellery Division chairman, reportedly said, adding that about four of the approximately 400 blue diamonds graded by GIA received the “Fancy Vivid Blue” grade. GIA also gave the gem a Type llb classification, meaning that it contains the chemical element boron, which gives blue diamonds its color by being trapped in the crystal structure during its formation.
Third, it’s pedigree. While statement diamonds do come to the market quite often these days, it’s rare that their origin is known. In this case, the 29.62-carat rough was mined in January 2014 at the Cullinan mine in South Africa. The mine is known for producing the top source for blue diamonds in the world but these gems still only account for 0.1 percent of its total diamond output, according to Gomes. It is also the source of at least two other important blue diamonds: the 30.62-carat “Blue Heart,” Fancy Deep blue stone on display at the Smithsonian Institution and the 27.64-carat Fancy Vivid blue “Heart of Eternity.” However, the mine’s most famous find is a colorless 3,106.75-carat diamond discovered in 1905. The rough diamond was cut into several polished gems. The largest is the 530.4-carat “Cullinan I” or “Great Star of Africa;” followed by the 317.4 carat “Cullinan II” or the “Second Star of Africa.” Both gems are in the Crown Jewels of the United Kingdom.
 |
| The Blue Moon in the Cora International office, taken in August 2014. Photo credit: Anthony DeMarco |
Fourth, it’s color. Gomes and Sotheby’s are describing the Blue Moon as “ocean blue,” “velvet blue,” etc… When I saw it the conditions weren’t ideal but I described it as aqua blue and translucent with the facets appearing as if they are wavelets on water. The blue is also evenly displayed throughout the gem.
Fifth, the combination of these factors. When looking at the pedigree, being Internally Flawless, Fancy Vivid Blue, and over 12 carats, it becomes a once in a lifetime offering. As one gemologist told me, “Try to go find another…. or even anything remotely like it and you’ll come up with a big goose egg.”
So while Gomes’ presentation skills may need polishing, her skill at identifying and buying quality rough; and making and selling world class diamonds is top notch.
Next week we’ll learn its true value.
A version of this story also appears on my Forbes.com blog
Please join me on the Jewelry News Network Facebook Page, on Twitter @JewelryNewsNet and on the Forbes website