I'd never heard of a diamond going into "surgery," so when I was invited to watch a massive 5-carat pink diamond worth $3.2 million go under the knife (aka, diamond cutting wheel), I was more than a little curious.
"One wrong move and the stone could just shatter, then millions of dollars right down the drain," Scott West tells me as he looks at a bright pink diamond in the palm of his hand.
The thought of shattering such a perfect gem makes me cringe, but Scott West knows what he's doing. He and his dad, Larry West, are the father-son duo who run L.J. West Diamonds, a wholesale diamond house in New York City that's been around for 41 years. The Wests are known as "diamantaires" in the industry, experts whose primary business is sourcing and cutting rare colored diamonds.
First a little back story on their pink rock…
"We purchased it at auction for $3.2 million, but we see the potential to add millions to its value," says Scott.
When Scott and his dad shelled out all that cash, they were drawn to the rock because they knew they could unlock more value in the stone by cutting it. In fact, they specialize in cutting and shaving colored diamonds in ways that improve cut, clarity, and color. In essence, a new shape can help a stone better reflect light, which can enhance or magnify a diamond's natural hue. In this case, they believe they can reshape this exotic pink rock to make it even more pink. They do it because a more intense pink color will make it even more valuable.
Scott says it's pretty simple, "The more color the stone has, the more valuable it is."
How much more valuable? Scott tells me, "If we are successful, we can double the stone's value overnight." So with this rock we're talking going from $3.2 million to some where north of $6 million.
The Wests say they confirmed through computer modeling that some tweaks to the stone's shape would make it better reflect light and pump up its pink hue — and that price-tag.
During the operation, they plan to remove a few micro millimeters from key points around the rock and shave the angle of a few facets. The diamond's 5-carat weight is big part of the reason it's worth so much money, so they want to get this done by removing as little weight from the stone as possible.
And since diamonds are one of the hardest materials in the world, instead of a scalpel, the tool in this surgery is a steel polishing wheel coated with diamond dust that spins anywhere from 350 to 600 RPMs. When you touch a diamond to the spinning wheel, in a split second it can shave micro millimeters from a facet. In the diamond business this delicate surgery is called "re-polishing." The risk is, if you apply too much pressure to the diamond or hold it at the wrong angle on the wheel, it could destroy the stone.
"We had a 20-carat yellow diamond that 'busted on the wheel' we call it... it went from $600,000 to $100,000 - just like that, it's the unlucky lotto," says Scott.
This delicate procedure is rarely seen outside the industry and this is the first time L.J. West Diamonds is allowing cameras inside the "operating room."
"When you re-polish these stones, it can be very nerve-wracking…but you have to go for it," Scott says.
We take an elevator three floors up from the L.J. West offices to an area called the gem-polishing room. It's a high-security area that requires us to be swiped in with a digital key and enter through two sets of security doors, where finally someone unlocks it and lets us through.
We enter a small, magenta-painted room with five diamond cutting stations. The air is thick, filled with microscopic particles of diamond dust and it smells kind of smoky. The guys sitting at these stations are called master diamond cutters. In order to reach this master level of diamond cutting, some of these craftsmen must practice for over 10 years with white diamonds before they acquire skills and patience needed to handle even rarer colored diamonds.
Scott takes the pink diamond he's carrying over to a man dressed in a navy blue button-down shirt that reminds me of something a wood shop worker would wear. His hands are covered in dust. Scott tells me he's one of the best diamond "surgeons" in America, but there are ground rules: I can't use his name in my reporting and our cameras can never be pointed at his face. (People who work in the diamond industry generally like to be discrete about their access to multi-million dollar diamonds so they don't become targets.)
The mysterious diamond master asks if we're ready, and I nudge my camera guy to make sure he's rolling. This guy's about to increase the value of this diamond by millions of dollars — or destroy it.
I hold my breath as he brings the stone closer to the spinning wheel and Scott's holding his breath too.
When the rock hits the wheel and the first spin chews into the stone, the sound is jarring. It's a lot like the terrible buzz you hear when having a cavity drilled by the dentist, only this is 10 times louder.
Scott's got $3.2 million on the line, so his eyes are glued to the wheel.
After about 30 minutes of spinning, checking facets and weighing the diamond on a scale, the diamond master says he's done for the day. Scott tells me it's too dangerous to do too much cutting in a single sitting, instead they pause because they don't want to over cut the stone and must let the "excited" stone relax: The speed of the wheel and grinding the stone against it causes the diamond to heat up and intensify the color. This color increase is often temporary, so Larry and Scott need to give this pink diamond time to cool down and rest while they re-evaluate the techniques they'll use to finish up the job.
In fact, the re-polishing process for this rock unfolds over more than 10 sessions and two weeks. In total, this diamond spends about six hours in the "operating room."
I visit the Wests on the final day of surgery and when I see the stone, I honestly can't tell any difference. The Wests explain it takes an expert eye to see it. Larry West whips out his jeweler's loupe, a small magnifying glass experts use in the business, to closely examine the newly shaped stone and announces, "Well, Scott I think you did the trick."
But before the Wests can pop the champagne, they need to ship the rock to the Gemological Institute of America (GIA), the institute that officially classifies gems by color and clarity on the industry's standardized diamond grading scale. Experts at the GIA will assess the rock to determine if the operation has really made the rock any more pink.
Two-weeks later, the GIA ships the rock back with the verdict, and Scott is thrilled, "We got the upgrade — from fancy pink to fancy intense pink."
That means the surgery was a success and the diamond's color is now a more "intense" pink than it was before. Amping up the pink moves the rock into an even smaller group of rare pink diamonds — and that boosts its value by a lot.
"Because it did so well, the stone is now worth over $7 million... it was a total home run," explains Scott.
Experts say this pink diamond has definitely increased in value by the millions, but it remains to be seen if L.J. West will find a buyer to pay $7 million for the diamond.
The increase in value is a big boost, but the Wests decline to share how it compares to what they have made off past stones.
The Wests have since set the seven-figure diamond into a platinum ring flanked by two white diamonds. They plan to take it on a tour to several V.I.P. events this fall where they believe they'll find a client who will "fall in love with it" and write them a big check to take it home.
Erica Wright is a producer for CNBC's special projects unit.
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