Lab-Grown Diamonds: Diamonds with a clear conscience

July 18, 2019

Lab Grown Diamonds vs. Natural Diamonds

In my quest to offer a truly environmentally-friendly and ethical alternative to mined diamonds, I’m so excited to start offering lab-grown diamonds! Not familiar? These diamonds are grown in laboratories that recreate the same environment that causes diamonds to form in the earth. Sounds simple, but it’s taken decades of trial and error to grow diamonds that have the exact same molecular composition and optical properties of a mined diamond. Even highly trained gemologists are unable to tell the difference! But as Vogue magazine points out, "it also couldn’t be more different, because there are zero doubts about its origin, carbon footprint, or human impact." 

So how are they formed? 

Lab-grown diamonds can be created using two different methods: High Pressure-High Temperature (HPHT) or Chemical Vapor Deposition (CVD). 

An HPHT diamond begins as a seed that’s placed in a growth chamber with graphite (carbon) and a catalyst mixture of powder and metals. The diamond seed, graphite, and catalysts are then exposed to extreme pressure (1.5 million pounds per square inch) and very high heat (around 1500 Celsius). The carbon begins to melt around the seed forming a rough diamond.

A CVD diamond begins as a thin layer of diamond as a foundation. It’s placed into a chamber and exposed to extremely high heat that rivals the intensity of the outer layer of the sun. The chamber is filled with carbon-rich gases, which are ionized, thus separating the carbon atoms. The free carbon atoms adhere to the thin layer of pure carbon diamond. Atom by atom, it grows into a jewelry-grade rough diamond. 

With both processes, the rough diamonds are then cut by master stone cutters. Up to 80-90% of their mass is often loss in order to maximize brilliance, clarity, and fire. Large diamonds are sent to a grading laboratory to get certified and laser-inscribed with a unique serial number. (Just like with mined diamonds, small accent-sized lab-grown diamonds also don’t come with grading reports.)

    Plasma Reactor (Image Courtesy of Diamond Foundry)   Raw Diamond Crystal (Image courtesy of Diamond Foundry)   Lab Grown Diamonds (image courtesy of Diamond Foundry)
Left to right: a plasma reactor, a rough diamond crystal, and cut diamonds. (All images are courtesy of Diamond Foundry)

 

How is a lab-grown diamond different than a moissanite? 

Moissanite and lab-grown diamonds have a similar appearance, but they have a very different molecular makeup from one another. Moissanite isn’t made from carbon, so it doesn’t have the same molecular, physical, or optical properties as diamond. In contrast, a lab-grown diamond has the same carbon molecular structure, physical properties, and optical properties of a mined diamond. That means lab-grown diamonds have identical fire, scintillation, and sparkle as mined diamonds. Lab-grown diamonds may have minute trace elements that may differ from a mined diamond, but these elemental differences cannot be seen under magnification or a jeweler’s loupe, and don’t affect the optical properties. These differences can only be detected via extremely specialized laboratory equipment. In addition to visual and molecular differences, moissanite ranks lower on the Moh’s Scale of Hardness, but it comes in at a much lesser price point.

Why We Love Lab-Grown Diamonds:

Each individual diamond grown in these foundries is just as unique as a mined diamond since each diamond will grow organically in the forming process with its own unique character. They are every bit as “real” as a mined diamond. In fact, lab-grown diamonds are getting some serious press. NPR says “They Sparkle Every Bit as Bright” and Fortune magazine even explains “Why Man-Made Diamonds Are Now Better Than Mined” diamonds. Another plus is that lab-grown diamonds are around 30% less expensive than their mined counterparts for the same quality. Not only are lab-grown diamonds a more socially and environmentally-friendly choice, but they’re budget-friendly too.

Don’t believe the media? Then take it from the “Patron Saint of Science” himself, Neil deGrasse Tyson. Watch him and an expert gemologist try to distinguish between mined diamonds and lab-grown diamonds: 

 

So how do lab-grown diamonds compare to moissanite and white sapphire? You can read a more in-depth comparison in this blog post.