What if that diamond on your finger is real, but an inscription says it was grown in a lab? Carlsbad gemologists and industry experts say while many people like these cheaper stones, some diamond purists are concerned these lab-grown counterparts could negatively impact the diamond industry.
So, what's the difference?
At the Gemological Institute of America labs around the world and in Carlsbad, gemologists are checking lots of precious stones every day, including diamonds.
James Shigley, a researcher there, said they can see whether a diamond came from the lab by shining a light through it.
“The light is produced by a light source that comes down to the optical cable which you are putting close to the diamond and using that light to look for a fluorescent pattern not present in lab-grown diamonds,” Shigley said.
The Gemological Institute, which has developed a diamond grading system followed around the world, has been doing this work for some time. But, lab and natural diamonds are basically the same, Shigley said.
"It's a diamond. It is exactly the same in terms of chemistry," he said.
The process is based on carbon, the element of diamonds in its pure form. So, when scientists want to grow diamonds, they start with a vacuum chamber to create a gaseous mixture of hydrogen and carbon.
Then they put a small diamond part, called a seed, into that mixture at an elevated temperature — around 900 to 1,200 degrees Celsius. The gas envelopes this seed, and grows pure carbon on top of it. The result is a larger diamond.
The only difference between this and a naturally formed diamond is time — a lot of time.
"Some of these natural diamonds are up to more than a billion years old," Shigley said. "They formed, maybe, a hundred miles down in the Earth and they were brought to the surface, maybe, by a volcanic eruption. And they survived that process."
Value based on rarity, not composition
And that's where the controversy with lab-grown diamonds comes in. Some in the industry believe these two products ought to be valued differently.
"There's never going to be that comparison of rarity between a natural diamond, which is quite rare. And a lab-grown diamond which can be produced in high quantities," Shigley said.
He said these diamonds are much cheaper than the natural ones. And that can create some industry challenges, said Ben Jenowski, a diamond industry consultant based in New York.
“If we see the ramping up of production of lab-grown diamonds which is already occurring and it's becoming less and less expensive, at some point we are going to undermine the value of true diamonds," Jenowski said.
The main impact will be on diamond miners, dealers and manufacturers who base diamond value on their rarity, he said. According to industry estimates, one diamond mine employs more than 1,000 people.
“The classic argument is that this has less environmental impact, there are no blood diamonds involved. To some degree that has validity," Janowski said.
So for the most part, Janowski said, the industry will depend largely on how the public feels. If more people don't mind buying a cheaper lab-grown stone, rather than shelling out the funds for the natural ones, that could potentially shake up the industry, he says.
Using science to get ahead
So, Shigley said, even though lab-grown and natural diamonds are the same, identification is necessary.
“There’s certainly a part of the consuming public that’s intrigued by lab-grown diamonds and the science and all this about them. And if they are properly disclosed and the pricing is correct they are perfectly fine on the market place," he said. "The problem is that they can be misrepresented either knowingly or unknowingly. And you may buy something and it’s not what you think you bought.”
Misrepresentation could also damage jewelers' reputations, Shigley said.
“These are increasingly available, these lab-grown diamonds in the marketplace and showing up in pieces of jewelry. Because they aren’t visually identifiable we have to have some additional testing with a device like this or in our laboratories.”
GIA has been producing reports or putting inscriptions on the stones to indicate where they came from. Now, Shigley said, the other piece of this process is educating the public on how they can check into their precious gems.
