Here's the short, surprising answer: a lab grown diamond is made of the same thing as a mined diamond: pure carbon arranged in the same crystal structure, with the same physical and optical properties. They have no chemical difference. A diamond pulled from deep in the earth and a diamond grown in a laboratory are, at the atomic level, the same material. The only thing that differs is where the carbon crystallized. Understanding this is the key to understanding why lab grown diamonds are genuinely, unambiguously real diamonds, and it starts with a single element.
It All Comes Down to One Element: Carbon
A diamond, whether mined or lab grown, is made of one thing: carbon. Not "mostly" carbon or "a carbon compound" pure carbon, the same element found in graphite, in the food you eat, and in every living thing on Earth.
What makes carbon so remarkable is that the same element can form wildly different materials depending on how its atoms are arranged. Arrange carbon atoms one way, and you get graphite, the soft, gray material in a pencil, so soft it flakes onto paper. Arrange the same carbon atoms differently, and you get diamond, the hardest known natural material on Earth. Same element, completely different result, purely because of structure.
This is the foundation of what a diamond actually is. A diamond isn't defined by where it comes from. It's defined by what it's made of (carbon) and how that carbon is arranged (a specific, incredibly strong crystal structure). Any material that meets both of those criteria is a diamond, and a lab grown diamond meets them exactly.
The Crystal Structure That Makes a Diamond a Diamond
The arrangement of carbon atoms in a diamond is what gives it every property it's famous for, so it's worth understanding.
In a diamond, each carbon atom bonds tightly to four other carbon atoms, forming a repeating three-dimensional lattice in the shape of tetrahedrons. This structure is called the diamond cubic crystal structure, and it's extraordinarily strong. Every atom is locked to its neighbors by powerful covalent bonds in every direction, with no weak points. This is why diamond is the hardest known natural material, and there's simply no easy way to break those bonds.
This same crystal structure is responsible for a diamond's other signature traits. Its brilliance and fire come from how this dense, ordered lattice bends and reflects light. Its ability to conduct heat rapidly comes from how efficiently the tightly bonded atoms transfer energy. Its durability, its sparkle, its resistance to scratching, and all of it flows directly from that specific arrangement of carbon atoms.
Here's the crucial point: a lab grown diamond has this same crystal structure. When a diamond is grown in a laboratory, the carbon atoms arrange themselves into the identical diamond cubic lattice, bonded the same way, in the same tetrahedral pattern. This isn't an approximation or a close copy. It's the same structure, which means the same hardness, the same brilliance, the same everything. The lattice doesn't know or care whether it formed over billions of years underground or over weeks in a lab; the physics is identical.
How Lab Grown Diamonds Get Their Carbon
If a lab grown diamond is just carbon in a diamond structure, how does a lab actually make that happen? The full process is a fascinating subject in its own right, but here's the short version of how the carbon becomes a diamond.
Laboratories use one of two main methods, both of which take carbon and create the conditions for it to crystallize into the diamond structure:
High Pressure High Temperature (HPHT) recreates the extreme conditions found deep in the earth, where natural diamonds form. A small diamond seed and a carbon source are subjected to immense pressure and intense heat, causing the carbon to crystallize into a diamond around the seed, layer by layer.
Chemical Vapor Deposition (CVD) takes a different route. A diamond seed is placed in a chamber filled with carbon-rich gas. The gas is energized so that carbon atoms separate from it and settle onto the seed, building up a diamond crystal atom by atom, layer by layer.
Both methods produce the same result: pure carbon arranged in the diamond crystal structure of a real diamond. The difference between them is the pathway, not the product. For the complete step-by-step breakdown of how each method works, see our full guide on how lab created diamonds are made.
Are Lab Grown Diamonds "Real" Diamonds?
This is the question that sits behind most searches about what lab grown diamonds are made of, so let's answer it directly and definitively: yes, lab grown diamonds are real diamonds.
This isn't a matter of marketing or opinion. It's settled on multiple levels:
Scientifically, they are identical. A lab grown diamond is pure carbon in the diamond cubic crystal structure the exact definition of a diamond. It has the same hardness (10 on the Mohs scale), the same brilliance and fire, the same density, the same thermal conductivity, and the same chemical composition as a mined diamond. There is no physical or optical property that distinguishes a lab grown diamond from a mined one on the basis of quality.
Officially, they are recognized as diamonds. In 2018, the U.S. Federal Trade Commission updated its definition of a diamond, removing the word "natural" from the definition. The FTC affirmed that a lab grown diamond is a real diamond and that describing it as "synthetic" could be misleading, since that word wrongly implies it's an imitation. In the eyes of the body that regulates how diamonds can be described and sold, lab grown diamonds are diamonds.
Practically, they are indistinguishable. Because they're the same material, lab grown diamonds pass every standard diamond test, including thermal conductivity testers, since they conduct heat exactly like mined diamonds. Even trained gemologists cannot tell a lab grown diamond from a mined one by eye; distinguishing them requires specialized equipment that detects tiny differences in trace elements or growth patterns, not any difference in what the stone fundamentally is.
The only real difference between a lab grown and a mined diamond is origin: one crystallized in the earth over a vast span of time, the other in a laboratory over a much shorter one. That difference in origin is exactly why they differ so dramatically in price, but it has nothing to do with what the diamond is made of or whether it's real. Our full comparison of lab grown versus natural diamonds explores this difference in depth.
Lab Grown Diamond Vs Diamond Simulant: An Important Distinction
Understanding what lab grown diamonds are made of also means understanding what they are not. Lab grown diamonds are often confused with diamond simulants, but these are completely different things, and the difference comes down to composition.
A lab grown diamond is made of carbon in the diamond crystal structure. It is a diamond. The lab isn't imitating a diamond; it's growing one.
A diamond simulant is a different material entirely that's designed to look like a diamond without being one. The two most common simulants are cubic zirconia (made of zirconium dioxide) and moissanite (made of silicon carbide). Neither is made of carbon, neither has the diamond crystal structure, and neither is a diamond. They're stand-ins that resemble diamonds to the eye.
This distinction matters enormously. When someone says "lab grown diamond," they mean a genuine diamond that happens to be grown in a lab. When someone says "diamond simulant," they mean an imitation made of something else. A lab grown diamond will pass a diamond tester because it's real carbon; a cubic zirconia won't, because it isn't a diamond at all. Confusing the two is one of the most common misunderstandings in the entire diamond world, but once you understand that it all comes down to composition, the difference is clear.
Why Composition Matters When You're Buying
Understanding what a lab grown diamond is made of isn't just interesting science, and it has real, practical value when you're shopping for one.
First, it means you can buy a lab grown diamond with complete confidence that you're getting a genuine diamond, not an imitation. The stone in a lab grown diamond ring is the same material as the stone in a mined diamond ring. You're not compromising on what the diamond is, only on where it came from, which is what makes it so much more affordable.
Second, it explains why lab grown diamonds are graded on exactly the same standards as mined diamonds. Because they're the same material, the 4Cs — cut, color, clarity, and carat apply identically to lab grown diamonds, and they're certified by the same gemological labs. A lab grown diamond's quality is measured the same way a mined diamond's is. Our complete 4Cs of diamonds guide explains how those grades work.
Third, it clarifies what you should and shouldn't pay attention to. Since a lab grown diamond is chemically identical to a mined one, the origin isn't a reason to question its beauty or durability, and it's simply the reason for the lower price. What matters when choosing one is the same thing that matters with any diamond: the quality of the cut, color, clarity, and carat, and the certification that verifies them.
At EthicStone, every lab grown diamond we sell is a genuine diamond, which is pure carbon in the diamond crystal structure, independently certified so you have verified proof of exactly what you're getting. You can explore our lab grown diamonds to learn more, or browse our lab grown diamond engagement rings to see real diamonds at a fraction of mined prices.
Frequently Asked Questions
⮞ What are lab grown diamonds made of?
Lab grown diamonds are made of pure carbon arranged in the diamond crystal structure — the exact same material and structure as mined diamonds. There is no chemical difference between a lab grown and a mined diamond; both are pure carbon in the same tetrahedral crystal lattice, which gives them identical hardness, brilliance, and properties.
⮞ Are lab grown diamonds real diamonds?
Yes. Lab grown diamonds are real diamonds, made of the same pure carbon in the same crystal structure as mined diamonds, with identical physical and optical properties. The U.S. Federal Trade Commission officially recognizes them as real diamonds. The only difference from a mined diamond is origin, not composition or authenticity.
⮞ What is the difference between a lab grown diamond and a mined diamond?
The only real difference is origin. A mined diamond crystallized in the earth over a very long time; a lab grown diamond crystallized in a laboratory over a much shorter time. They are chemically, physically, and optically identical, both pure carbon in the diamond crystal structure. This origin difference is why lab grown diamonds cost far less.
⮞ Are lab grown diamonds the same as cubic zirconia?
No. Cubic zirconia is a diamond simulant made of zirconium dioxide, a completely different material that only looks like a diamond. A lab grown diamond is made of carbon and is a genuine diamond. Lab grown diamonds pass diamond testers because they're real diamonds; cubic zirconia does not.
⮞ How are lab grown diamonds made?
Lab grown diamonds are made using one of two methods: High Pressure High Temperature (HPHT), which recreates the Earth's diamond-forming conditions, or Chemical Vapor Deposition (CVD), which builds a diamond from carbon-rich gas. Both take carbon and crystallize it into the diamond structure, producing a real diamond.
⮞ Do lab grown diamonds have the same chemical composition as mined diamonds?
Yes, the same. Both lab grown and mined diamonds are pure carbon arranged in the identical diamond cubic crystal structure. There is no chemical difference between them whatsoever. This is why they have the same hardness, brilliance, durability, and every other property that defines a diamond.
⮞ Are lab grown diamonds as hard as real diamonds?
Yes. Lab grown diamonds score 10 on the Mohs hardness scale, the same as mined diamonds, because they have the identical carbon crystal structure. They are just as hard, durable, and scratch-resistant as any mined diamond, making them equally suitable for everyday wear in engagement rings.
⮞ Why are lab grown diamonds cheaper if they're the same material?
Lab grown diamonds are cheaper because of how they're produced, not what they're made of. Growing a diamond in a lab over weeks is far less costly than mining, which involves extensive excavation and a long supply chain. The identical material at a fraction of the price is exactly why lab grown diamonds have become so popular.
⮞ Can you tell the difference between a lab grown and mined diamond?
Not by eye. Because they're the same material with the same properties, lab grown and mined diamonds look identical, and even trained gemologists cannot distinguish them without specialized equipment. That equipment detects subtle differences in trace elements or growth patterns related to origin, not any difference in what the diamond is.
⮞ Are lab grown diamonds fake or synthetic?
Neither, in any meaningful sense. Lab grown diamonds are real diamonds made of the identical material as mined ones. The FTC has advised against calling them "synthetic" because that word wrongly implies imitation. They are genuine diamonds that were grown rather than mined, real in every way that matters.