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Lab-grown Diamonds: What They Are and What You Need To Know

by David Weliver

A lab-grown diamond is a real diamond. It doesn’t differ in any way from an earth-created diamond except how it came into being. Buying a lab-grown diamond eliminates any environmental or political concerns and may save you money. Here’s everything you need to know about laboratory-created diamonds.

What is a lab-grown diamond?

As the name suggests, a laboratory-grown diamond is a diamond that is grown in a lab using the same extreme forces — temperature and pressure — that form earth-created diamonds. 

There are exactly zero chemical, optical, or physical differences in a lab-grown diamond, compared to an earth-created diamond

Lab-grown diamonds even have inclusions, the tiny flaws that are in virtually every earth-created diamond. 

That’s not surprising, since, as we’ll see, the ingenious methods of creating diamonds mimic the earth’s natural processes. 

But before we answer questions such as how on earth humans are able to create diamonds, let’s debunk a common myth.

Are cubic zirconia and moissanite lab-grown diamonds?

No! Cubic zirconia and moissanite are two inexpensive types of imitation diamonds. They are not lab-grown diamonds.

Cubic zirconia (CZ) are cubic zirconia. They are almost always sold as a diamond substitute, or a diamond simulant, but they’re not diamonds. 

Moissanite gemstones are moissanite. They also might be marketed as a diamond substitute, or a diamond simulant. But they’re not diamonds. 

Diamonds are diamonds. These include earth-created diamonds and laboratory-grown diamonds. There are zero differences between lab-grown and earth-made except for where they are made. 

How are lab-grown diamonds different than cubic zirconia and moissanite?

Cubic zirconia and moissanite are not as hard as diamonds. They also differ from diamonds chemically. Furthermore, they have different optics — light behaves differently in them than in diamonds. 

So why do I mention CZ and moissanite at all, in this article on laboratory grown diamonds? 

The reason is that quite a number of uninformed bloggers (and even on some sites you’d expect to be better informed) refer to cubic zirconia and moissanite as “synthetic diamonds.” 

They’re simply not. They are different materials, end of story.

Are lab-grown diamonds synthetic diamonds? 

Sort of. Lab-grown diamonds are sometimes called synthetic diamonds because they are synthesized in a lab. But a lab-grown diamond is indistinguishable from an earth-created diamond.

In this case, “synthetic” is a somewhat misleading term. 

The word can give the impression that lab-grown diamonds are somehow different from earth-created ones.

But they’re not different at all, except in how they came into being. 

Is there a difference between “lab-grown” and “lab-made”?

No difference at all. Both terms refer to diamonds which are made in a lab. These are merely different wordings.

Who invented lab-created diamonds?

Howard Tracy Hall was a chemist at General Electric considered to be the first person to successfully grow a diamond in a lab.

Though his work would be worth billions of dollars to the diamond industry, he received only $10 for the discovery.

There were claims of success in creating diamonds in labs in the late 19th Century and first half of the 20th century. But none were confirmed or reproducible. So, as far as science and history are concerned, lab-grown diamonds did not exist until Hall’s discovery.

The first documented, reproducible lab-grown diamond was devised by Hall in 1954.

He was an unrecognized chemistry genius at General Electric. Four years of experiments and failed attempts, and a lack of respect from his colleagues and managers, finally ended in his triumph. 

Making the success even sweeter for Hall, no doubt, was that competing members of the General Electric lab working on the problem had access to a 1,000-ton press, but Hall was restricted to using only the 400-ton press. 

He was everyman, in that sense. The underdog, overlooked, discriminated against, in office politics. 

To attempt these experiments, the competitors explored many variables. One of these variables was the container in which carbon was compressed.  Hall was at a disadvantage here, too. He had to make do only with hardened steel, rather than even harder specialized materials available to other members of the team. (It’s called Carbaloy …  don’t ask! It’s tungsten carbide mixed into cobalt.) 

So with only hardened steel to work with, and the measly 400-ton press, Hall had to get creative. So he did. He designed a radically new donut-shaped container outfitted with curved and tapered pistons. 

If you have a look at the contraption, I think you’ll agree: Hall and the container offer a look that does not disappoint. The monkey wrench in his hand is also impressive.  I’d say Howard Tracy Hall is the Mick Jagger of chemists. 

With substandard materials, and a substandard press, it was the the design he worked out, and the physics of it, that put Hall over the goal line. 

In went the ingredients (iron sulfide and powdered carbon). Then the pressure was brought to 100,000 atmospheres. And it was heated to 2,900 degrees Fahrenheit. 

Thirty-eight minutes later, the diamonds were cooked. 

Out came the diamonds. (Industrial grade, but still — a giant leap for mankind. Hall was the winner of this historic contest. He had just mimicked processes that take centuries deep inside planet Earth, to create diamonds.)

It spawned an entire industry manufacturing industrial grade diamonds. GE was poised to make a fortune. 

It’s safe to say, he got Employee of the Month. That’s actually a joke. What’s no joke is this: GE gave him a $10 savings bond. Not $10 million. Ten. Dollars.  

GE was able to grow diamonds in the lab, but they weren’t exactly gemstones. They were low-grade — ugly, small, and suitable only for industrial applications. They still were worth fortunes, because mining and heavy industry has no end of need for industrial-grade diamonds, the hardest substance on earth.

The story has a happy ending, though. 

Hall left GE and created an even better, more radical design of his press. One that didn’t rely on any GE patents. With this technology, he started his own diamond-making enterprise. He awesomely name it … MegaDiamond. 

It was acquired by various companies through the years and has been absorbed into Schlumberger, an international oil and gas drilling company. 

How are lab-grown diamonds made?

Two different processes are used to make lab-grown diamonds. Both use a tiny “seed” diamond. Chemical vapor deposition (CVD) puts tiny layers of vaporized carbon over the seed. The other method replicates nature’s process by subjecting carbon and the seed to intense pressure and heat.

Chemical vapor deposition (CVD)

To make lab-grown diamonds using the CVD method, vaporized carbon is laid down in layers over a “seed” of a tiny diamond. 

This process gets complicated. But it’s fascinating. The short version is: 

1. Put a tiny diamond “seed” inside a chamber that can be compressed and heated to ungodly heat and pressure. 

2. Pump into the chamber gases that are full of carbon. Microwave it to the aforementioned ungodly temperatures. (Say, 1,400 degrees Fahrenheit.) Things get so hot, the molecular bonds of the gases are severed. That means carbon is floating around freely. It latches directly onto the “seed” diamond. And as it “fits in” to the chemical surface of the seed diamond, these new layers of carbon form layers of diamond.  

It can result in beautiful gemstones. 

High pressure, high temperature (HPHT)

This method relies solely on subjecting carbon to intense heat and pressure.

This method has come a long way since Howard Tracy Hall first created it in 1954. It results not only in diamonds for industrial use, but can be fine-tuned to create diamonds for gemstones. 

1. First, a tiny diamond is placed into a bit of carbon. 

2. This ball of carbon is then compressed with 1.5 million pounds per square inch. (Yeah, that’s a lot.)  Then, the heat is turned up to 2,700 degrees Fahrenheit. 

3. At this point, the carbon becomes molten. As the molten carbon forms up against the diamond crystal, it crystalizes into diamond form, just like the vaporized carbon atoms do in the CVD method. 

Who makes lab-grown diamonds? 

There are a handful of companies that manufacture laboratory-grown diamonds, including the most famous diamond company of all, De Beers.

For years, De Beers tried to hold out against the lab-grown diamond onslaught. They preferred to sell only what they’d always sold: earth-mined diamonds. 

But in 2018, De Beers got into the diamond gemstone manufacturing business as well. 

Other makers of lab-grown diamonds include: 

How long does it take to make a lab-grown diamond?

Creating a diamond in a lab can take as little as two weeks and up to 10 weeks.

This elapsed time refers only to their creation. When lab-made diamonds come out of the chamber, they are rough. Diamonds sold for jewelry must be cut and polished, which is a different process.

They come out of the chamber roughly equivalent to earth made diamonds brought up from a mine. They look vaguely like rocks!

How can you tell the difference between a lab-grown diamond and an earth-grown diamond? 

Lab-grown diamonds sold by any reputable retailer are clearly labeled and documented.

If you have any doubt as to a diamond retailer’s reputation, check the BBB, Trustpilot, and other online review sites. If you can’t find information about the retailer, consider looking elsewhere.

You can’t go wrong with James Allen, Blue Nile, Brilliant Earth and of course major chains like Tiffany, Cartier, Zales, Jared, and others (which are really too numerous to mention). 

On the other hand, if you’re buying from some random eBay seller, you’ve got more things to worry about than whether your diamond is human-made or earth-made.

Please. Just. Don’t buy from any retailer but a real jeweler such as James Allen, etc., that you know is legitimate. Anything that’s a huge discount or too good to be true is, in fact, no exceptions, too good to be true!

Are lab-grown diamonds marked in any way? 

All laboratory-created diamonds are labeled as such via a tiny engraving right on the diamond. In this sense, lab-grown diamond jewelry can be easily distinguished from authentic or natural diamonds.  

It’s an almost microscopic etching on the girdle of the diamond. It usually says, literally, “Lab-Created” or “Lab-Grown”. 

Many diamonds also have pertinent information like serial numbers etched into their girdles. This is true whether they are lab-made or earth-made. 

The etching is applied at the time a diamond is cut. Remember, just because these are lab-grown does not mean that they are not high-quality diamonds. 

Are lab-grown diamonds better?

Laboratory grown diamonds differ from earth mined diamonds as a class, in one important way: They don’t have the same range of color flaws.

This makes perfect sense, as we think it through. Since the market overwhelmingly prefers diamonds to be as colorless as possible, the companies creating diamonds try to make them that way. As colorless as possible. 

That means all the various shades of yellow which we may find in earth-created diamonds do not appear as often in lab-made diamonds. 

The GIA has even tried to account for this difference as a class by grading the color of lab-grown diamonds in a slightly different way than they grade the color of earth-created diamonds. 

Another way to put it: Lab-grown diamonds, taken all together, have much better color than earth-grown diamonds, taken all together. 

This can be an advantage to you, as a buyer, because despite this color disadvantage, demand tends to be higher for earth-created diamonds.

Consumers still show a preference for earth-created diamonds. There are several reasons for this, including the fact that people are still digesting the existence of human-made diamonds. A lot of confusion still surrounds it. So most people, for such an important purchase, tend to revert to what they know and feel comfortable with: earth-created diamonds. 

Of course, the higher demand for earth-created diamonds tends to make them more expensive. 

Which means, in principle (and often in fact), you can find laboratory-created diamonds with excellent color for significantly less than you’d expect to pay for that color among earth-created diamonds. All because people are naively prejudiced against lab-grown diamonds. 

Something that also needs to be taken into account with lab grown diamonds is that you can be a conscious shopper, because you don’t have to worry as much as the environmental impact of diamond mining, or the issues surrounding unethically sourced diamonds, such as blood diamonds. Lab-grown diamond technology allows for every diamond you buy to be an ethically-sourced diamond. 

One of the biggest benefits of lab grown diamonds is that the creation process involves very low carbon emissions, while still allowing makers to create diamonds with perfect symmetry, ideal chemical properties, and in a range of styles, cuts, and many color grades too. 

Where to buy lab-grown diamonds

Although not every jeweler sells lab-grown diamonds, they are becoming increasingly popular. You can find thousands of lab-grown diamonds for sale at leading online jewelers including Blue Nile and James Allen. Before going into a physical jewelry space, we do recommend looking for a reputable and knowledgeable jeweler online. 

Blue Nile sells an exclusive collection of lab-grown diamonds from Lightbox, a leading maker of lab-created diamonds.

James Allen also has over 10,000 lab-created loose diamonds to choose from with which you can design your own engagement ring.


What are laboratory-grown diamonds? They’re exactly the same thing as earth-made diamonds. They’re just made in a lab. 

Laboratory-grown diamonds are identical in every way to earth-created diamonds. As a group, the only difference is that lab-grown diamonds have a narrower range of colors than earth-created diamonds. (They’re engineered this way because that’s what buyers want.)

Lab diamonds are often (but not always) less expensive, since many people still prefer earth-made diamonds. 

But lab-grown diamonds are rapidly growing in popularity, especially since it’s 110% clear they’re not connected to wars and conflicts, and they were not ripped from deep in the earth with mining equipment. 

Lab-grown diamonds are perfectly legitimate diamonds. The bottom line here is that if you aren’t an expert, you’re not going to notice a difference between natural and laboratory-grown diamonds. Both mined and lab-grown diamonds can make for an excellent engagement ring! Let’s take a quick look at some of the best jewelry brands out there that current offer lab grown diamonds. 

Recommended Jewelers

James Allen

James Allen logo

James Allen is the most competitive diamond vendor with more than 150,000 loose diamonds in inventory. They have been a leader in selling diamonds online and pioneered 3D imaging so you can see the exact diamond you're buying in exquisite detail. You'll find it hard to beat James Allen in terms of price or selection. Read our James Allen review.

Shop James Allen »


Whiteflash logo

Whiteflash is the home of "A Cut Above" diamonds which are among the best quality round- and princess-cut diamonds in the world. With superior diamond photographs and videos, Whiteflash's diamonds seem to come to life -- even online. Read our Whiteflash review.

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Brilliant Earth

Brilliant Earth logo

Brilliant Earth is the global leader in ethically-sourced jewelry. Brilliant Earth goes above and beyond existing standards to offer “Beyond Conflict Free Diamonds” that they select for their ethical and environmentally-responsible origins. With over 120,000 diamonds in inventory, you can be sure to find your perfect diamond and feel good knowing it was responsibly-sourced. Read our Brilliant Earth review.

Shop Brilliant Earth »

Blue Nile

Blue Nile logo

Blue Nile is the world's largest online jeweler. Their reputation for quality and customer service is unparalleled in the industry. Blue Nile offers free shipping, a 30-day return policy and satisfaction guarantee. Read our Blue Nile review.

Shop Blue Nile »