Lab-Grown Diamonds and Gems: Are They Real?

16-04 Lab-Created Diamonds and Gems: Are they the real things?

Marty Peterson: A diamond ring is the symbol of love that most women receive when they get engaged. That sparkling stone in the beautiful setting might be an heirloom handed down from grandmother or great-grandmother. It could also be a new ring with a diamond that came from a mine in some faraway place like Africa, or Russia. Or…it could be a ring with a stone created … in a laboratory! That third possibility is becoming more popular these days – especially among young people – because of the problems that occur when diamonds are mined…

T.J. Walker: There’s an awful lot of environmental impact. That’s the beauty of lab-grown diamonds is that they have, according to Frost & Sullivan, only one-seventh of the impact on the soil, land, water, air when you factor it all in. There’s a tremendous impact in pulling diamonds out of the ground from mines.

Peterson: That’s T.J. Walker, spokesperson for Pure Grown Diamonds, a company that creates genuine diamonds in their laboratory in Singapore…

Walker: You have to dig and often you’re digging hundreds, even thousands of tons of soil out. You have to use a lot of water. In the case of the Philippines, for example, young children, according to Amnesty International, as young as 11 years old, are diving into water as much as 25 meters down with a little tube in their nose. And they’re just pulling it with their fingers in a mine that’s under water. So, it is very tough conditions.

Peterson: To understand what a feat creating diamonds in a lab is you need to understand how they form naturally in the earth. We asked Marcia Bjornerud, professor of geology at Lawrence University in Appleton, Wisconsin…

Marcia Bjornerud: They have a really unusual geological origin. They’re pure carbon, which normally at the surface of the earth occurs as graphite, which is actually what pencil “lead” is made of. Graphite is so soft that it scratches off when you write with it on a sheet of paper. Diamond, of course, is the hardest known naturally occurring material. The big difference between those two forms of carbon is that diamond forms at immensely high pressure. And, in fact, it forms only on earth in two circumstances: either deep in the earth’s mantle, far below the crust on which we live and is brought up by still poorly understood localized eruptions of rock called kimberlites or, the only other way it’s formed is by meteorite impact when, briefly, a meteorite striking the earth, pressures get so high from the shockwave that you can form tiny little diamonds. Most of the mined diamonds that are used for jewelry and industrial purposes are from the kimberlite volcanic rocks that I mentioned.

Peterson: So how do you recreate all of that in a laboratory? Bjornerud says it was done quite a few years ago, but not for the diamonds in your jewelry…

Bjornerud: Diamonds have been synthesized for at least 50 years in very high-pressure apparati. I think General Electric was the first company to create diamonds. They were not trying to make gemstones, but diamond is a really important industrial mineral for abrasives and for cutting of hard materials like glass and other stone, so they were interested in synthesizing industrial diamond and developed a process by which you could generate these extremely high pressures in the lab.

Peterson: He wouldn’t give us any secret information about how to create diamonds in the lab, but Walker says that the process today is very fast and efficient compared to Mother Nature’s…

Walker: You start with a diamond seed which is made of pure carbon. It’s then put into a “greenhouse” where it grows. It’s a crystallization process. It grows after nine to 12 weeks, and then you cut the diamond, you polish it, you mount it, you sell it and it really takes about nine months from the very beginnings until the point when it can be on the finger of a customer.

Peterson: He says that you can get a lab-created diamond in a number of different colors, just as you can mined diamonds…

Walker: We have fancy pink, bright yellow and colorless or white diamonds, so almost anything you see in nature from mined diamonds you can create in lab-grown diamonds. But it’s not a simple matter of just typing in a few coordinates. There’s still a great deal of randomness to it because it is a natural crystallization process.

Peterson: But are lab diamonds really diamonds? Can you tell the difference between them and a mined diamond of the same quality? Walker and Bjornerud say…no…

Walker: A lab-grown diamond is a natural diamond; it just wasn’t from under the ground. But if you took a lab-grown diamond to a gemologist and they looked at it under one of those loupes they would not be able to tell the difference between a lab-grown diamond and a mined diamond, because they are both genuine diamonds.

Bjornerud: This newer method is starting to make the major diamond companies a little bit nervous because so far they haven’t found diagnostic tests that would allow them to distinguish synthetic from natural ones.

Peterson: Walker says that his company’s diamonds are Type-2-A, which means that their quality is in the top one- to two-percent of all the diamonds in the world. The Elizabeth Taylor Diamond, and the famous Koh-I-Noor diamond are in that category. There are flaws in many diamonds called “inclusions,” which you might not want in your jewelry, but Bjornerud says are very interesting to geologists…

Bjornerud: The lore of diamonds is partly wrapped up with the fact that they did come from deep in the earth and to geologists it is interesting to study some of these inclusions in the diamonds because, for example, there’ve been a couple of cases where it’s clear that the carbon from which the diamonds formed actually started at the surface of the earth, may have been subducted through plate tectonic recycling deep into the mantle of the earth and then found its way back to the surface again. And that’s the story is certainly interesting. And if that matters to diamond buyers it’s not something that a synthetic diamond carries with it.

Peterson: Of course diamonds aren’t the only stones that people use for jewelry. Bjornerud says that any stone that you find beautiful can be cleaned up, polished and used in a ring or necklace. It’s mostly a question of taste and trends. One thing that all jewelry stones have in common is that they come from minerals…

Bjornerud: To a geologist a mineral is a crystalline substance, that means something in which the atoms, the elements that make it up, have a well-defined pattern in which they sit, and also a well-defined formula. So quartz, for example, one of the commonest rock-forming minerals is simply silicon dioxide, SiO₂, and in the lattice of the quartz crystal those silicon and oxygen atoms have a particular seating arrangement and that makes it a mineral. And gemstones are just expressions of minerals in which the crystals have grown with unusual translucency.

Peterson: You might be surprised to find out what two very desirable and popular stones are made of, and how they are grown in a laboratory…

Bjornerud: Many people don’t realize that ruby and sapphire are technically the same mineral which geologists would call “corundum.” It’s just aluminum oxide; it’s used in sandpaper if it’s not a gem-quality version. And the difference in color between ruby and sapphire is due to tiny differences in trace elements that are in the corundum. But they’re technically the same mineral. Rubies and sapphires are primarily produced by melting powdered aluminum oxide and then allowing that to solidify and crystalize, and that’s the way that’s done and apparently it doesn’t require quite as much technical apparatus so those are relatively inexpensive.

Peterson: Speaking of inexpensive, lab-created diamonds are not as costly as mined ones, although they aren’t cheap. Walker says, though, that engaged couples might want to look into buying a ring with a lab-grown diamond and use their savings for some other expenses…

Walker: The typical engagement ring in the United States, for example, people spend often five thousand dollars for a one-carat diamond. The very same one-carat diamond that is a lab-grown diamond at Pure Grown Diamonds would cost more like three thousand dollars. That means you’ve got a couple thousand dollars more to spend on a honeymoon, a wedding, a down payment of a house. When people are buying diamonds they often have a lot of other big expenses going on in their life, and that’s why they are attracted to the value of lab-grown diamonds.

Peterson: If diamonds that are lab-grown are identical to mined versions, how do you know which one you’re getting? Walker says that it should be pointed out to you by the manufacturer and the jeweler…

Walker: Now what we do, because we’re so proud of what we do, is we actually inscribe under the girdle on each diamond and “LG” for “lab-grown” and the particular identifying number of that diamond so you know exactly what you’re getting. Now, this is not visible to the naked eye, and I can tell you, personally, I’ve looked for this using a loupe, I couldn’t even see the numbers. So it’s in no way distracting. So we ask all jewelry stores, anyone in the supply chain to let people know because we want people to know exactly where it came from.

Peterson: Walker adds that if you’re in the market for a diamond of any kind, you should always go to a reputable jeweler and ask what kind of diamond it is and where it came from. You can find out more about lab-grown diamonds and where to find them, on Walker’s company’s website, PureGrownDiamonds.com. For more information on Marcia Bjornerud and Lawrence University, visit Lawrence.edu. For more about all of our guests, visit our site at Viewpointsonline.net. You can find archives of past programs there and on iTunes and Stitcher. Our show is written and produced by Pat Reuter. Our production directors are Sean Waldron and Reed Pence. I’m Marty Peterson.