A lab grown diamond is a real diamond — not an alternative, not an imitation, and not a marketing term for something lesser. It is a diamond grown inside a laboratory rather than pulled from the earth, but chemically, physically, and optically identical to any mined stone in existence.
Understanding what that actually means — and why it matters — is what this page is for.
The Simple Definition
A lab grown diamond is a gemstone made entirely of carbon atoms arranged in the same crystal lattice structure as a mined diamond. Both form under conditions of extreme heat and pressure — one over billions of years deep in the Earth's mantle, the other over a matter of weeks inside a controlled growth chamber. The conditions are replicated; the result is the same.
That sameness isn't a marketing claim. It's measurable science:
- Hardness: 10/10 on the Mohs scale — the hardest material on Earth, identical to mined diamonds
- Refractive index: 2.417–2.419, which is what gives diamonds their signature brilliance and fire
- Chemical composition: Pure carbon (C), bonded in a cubic crystal lattice — the precise definition of a diamond
- Density: 3.51–3.53 g/cm³ — same as a mined stone
- Thermal conductivity: Among the highest of any material, which is why diamonds feel cold to the touch
A professional jeweler looking through a loupe sees a diamond. A standard diamond tester reads a diamond. A spectroscope shows the diamond spectrum. The only instruments that can detect a difference are specialized gemological devices that look for microscopic growth patterns — not visual differences, not quality differences, just origin signatures.
What a Lab Grown Diamond Is Not
This is where most of the confusion in the market lives, so it's worth being direct.
Lab grown diamonds are not cubic zirconia. CZ is made from zirconium oxide — an entirely different material. It's softer, has a different refractive index, clouds over time, and fails a standard diamond tester immediately. Comparing a lab grown diamond to CZ is like comparing a river pearl to a plastic bead.
Lab grown diamonds are not moissanite. Moissanite is silicon carbide — beautiful in its own right, but a completely different stone with different chemistry, different hardness (9.25 vs. 10), and a slightly different optical character. It is not a diamond.
Lab grown diamonds are not "synthetic" in any diminishing sense. Gemologists use the word "synthetic" to simply mean "not formed in the Earth" — a technical classification of origin, not quality. The U.S. Federal Trade Commission made this official in 2018, removing the word "natural" from its legal definition of a diamond entirely. Under federal law, a lab grown diamond that meets the carbon-crystal-lattice criteria is a diamond.
What Are They Actually Made Of?
Every diamond — mined or lab grown — is made of pure carbon. What makes a diamond a diamond isn't where the carbon came from. It's how the carbon atoms are arranged.
When carbon is forced into a specific tetrahedral crystal lattice structure under extreme heat and pressure, it becomes diamond. Under slightly different conditions, the same carbon becomes graphite — pencil lead. The arrangement is everything.
In nature, that arrangement happens roughly 100 miles below the Earth's surface: temperatures exceeding 2,000°F, pressures over 700,000 pounds per square inch, and a timeline measured in millions to billions of years. Volcanic activity eventually pushes those crystals toward the surface.
In a lab, scientists recreate those same essential conditions — the same carbon source, the same temperature and pressure parameters — and compress the timeline to weeks. The carbon atoms behave the same way. The crystal structure that forms is the same structure. The diamond that results is the same diamond.
How Are They Made? (The Short Version)
There are two primary methods used to grow diamonds in a laboratory. Both start with a tiny diamond "seed" — a thin slice of existing diamond — and both produce a genuine diamond crystal.
HPHT (High Pressure High Temperature) mimics the Earth's mantle. The seed is surrounded by carbon material and subjected to temperatures around 1,400–1,600°C and pressures of roughly 50,000–60,000 atmospheres. Carbon dissolves and crystallizes around the seed, growing layer by layer over 2–4 weeks.
CVD (Chemical Vapor Deposition) takes a different route. The seed goes into a vacuum chamber filled with a hydrogen-carbon gas mixture. Microwave energy ionizes the gas into a plasma, and carbon atoms rain down onto the seed, building up a crystal layer by layer. CVD runs at lower temperatures (~900–1,200°C) and is particularly well-suited for producing high-clarity, high-color stones.
For a full deep-dive on both processes, see our guide: How Are Lab Grown Diamonds Made.
Are Lab Grown Diamonds Graded?
Yes — lab grown diamonds are graded by the same independent gemological laboratories as mined diamonds, using the same Four Cs framework:
| Grade | What It Measures |
|---|---|
| Cut | How well the diamond is faceted to interact with light |
| Color | Graded D (colorless) to Z (light yellow/brown) |
| Clarity | Presence or absence of internal inclusions |
| Carat | The weight of the stone |
IGI (International Gemological Institute) continues to apply full individual 4Cs grades to lab grown diamonds — the same D-to-Z color scale and clarity grades used for mined stones. If your certificate is from IGI, you'll see specific grades like "E color, VS1 clarity."
GIA (Gemological Institute of America) changed its approach in October 2025. Rather than issuing individual letter grades, GIA now classifies lab grown diamonds as either "Premium" or "Standard" based on an overall assessment of color, clarity, and cut. GIA-graded lab grown diamonds issued before October 2025 retain their original full 4Cs reports, which remain valid. New submissions receive the simplified quality assessment instead.
The practical implication: if precise color and clarity grades matter to you when comparing stones, look for IGI-certified lab grown diamonds. For a full breakdown of what this means when you shop, see our Lab Grown vs. Natural Diamond guide. You can also explore our Diamond Education: The 4Cs guide to understand how each grading factor affects what you see in person, and find answers to common certification questions in our FAQ.
One Surprising Detail: Lab Grown Diamonds Are Often Purer
One side effect of the CVD growth process is that it typically produces a more chemically pure diamond than what forms naturally. About 98% of mined diamonds contain nitrogen clusters trapped during formation — what gemologists call Type Ia — which is responsible for the slight warmth in color at lower grades (Gemological Institute of America). CVD diamonds form in a nitrogen-controlled environment, producing Type IIa stones with essentially no nitrogen. It's not a marketing claim — it's simply what happens when the growth conditions are controlled rather than geological.
So Why Does This All Matter?
Because once you understand what a lab grown diamond actually is, the value proposition becomes obvious.
You're not compromising. You're not choosing the "budget version." You're choosing the same stone — formed through the same process, graded by the same standards, with the same physical properties — at a price that reflects what it genuinely costs to create exceptional diamonds, not the overhead of a century-old mining and distribution system with generations of marketing mythology built into the price.
At LabGrownDiamonds.com, our position has always been simple: a diamond is a diamond. The brilliance is real. The hardness is real. The certificate is real. The only difference is what you paid to get there.
What Do Lab Grown Diamonds Cost Compared to Mined Diamonds?
As of 2026, lab grown diamonds retail for approximately 70–85% less than mined diamonds of equivalent quality — and the gap widens significantly as carat weight increases.
All comparisons below are apples-to-apples at the quality standard that actually matters: F color or better, VS clarity or better, Excellent or Ideal cut. Lower-quality stones are cheaper on both sides — these figures reflect what you're paying for a diamond that genuinely performs.
Loose diamonds (round, F+ color, VS clarity, Excellent cut):
- 1-carat natural diamond: ~$5,000–$7,000
- 1-carat lab grown diamond: ~$750–$1,200
- Savings: roughly $4,000–$6,000 on a single stone
Stud earrings (2 carats total weight, 1 carat per ear, F+ color, VS clarity):
- Natural diamond studs: $10,000–$18,000+
- Lab grown diamond studs: starting around $1,500–$2,500
- The same earrings. The same sparkle. A difference that can reach $15,000 or more.
Engagement rings (2-carat center stone, F+ color, VS clarity, Excellent cut):
- Natural diamond ring: typically $15,000–$25,000+
- Lab grown diamond ring: average around $3,000–$6,000
- That's a meaningful sum that could go toward a down payment, a honeymoon, or simply starting your life together without debt.
The gap is largest at bigger carat weights, because natural diamond scarcity compounds dramatically with size while lab grown production doesn't follow the same constraints. A 3-carat natural diamond at top quality can cost $50,000–$100,000+. A comparable lab grown stone: $2,500–$5,000.
This price difference doesn't reflect a difference in the stone. It reflects a difference in what it costs to bring one to market. Natural diamond prices include the overhead of global mining operations, a complex multi-country distribution network with many layers between mine and finger, and over a century of carefully managed market positioning. Lab grown diamond prices reflect what it actually costs to grow, cut, certify, and deliver an exceptional diamond — which has dropped significantly as the technology has scaled.
The result: you can own a significantly larger, higher-quality diamond for the same money — or the same stone for dramatically less. Neither means you're getting a lesser diamond. You're getting the same diamond, priced more honestly.
Explore our collection of lab grown diamond stud earrings, engagement rings, and loose diamonds — all F+ color, VS+ clarity, and Excellent/Ideal cut.
Frequently Asked Questions
Are lab grown diamonds the same as real diamonds? Yes. Lab grown diamonds are real diamonds — identical in chemical composition, hardness, brilliance, and durability to mined diamonds. The only difference is where they were formed: underground over billions of years versus in a laboratory over several weeks.
Will a lab grown diamond pass a diamond tester? Yes. Standard diamond testers measure thermal conductivity, which is identical in lab grown and mined diamonds. A lab grown diamond will test as a real diamond every time.
Do lab grown diamonds look different from mined diamonds? No. Lab grown and mined diamonds are visually identical — to the naked eye, under a jeweler's loupe, and in photographs. The only instruments that can detect a difference are specialized gemological devices that look for microscopic growth patterns invisible during normal wear.
Are lab grown diamonds a good investment? Neither lab grown nor mined diamonds are reliable financial investments for most buyers. Both lose significant value on the secondary market compared to retail price. Lab grown diamonds cost substantially less to begin with, which means less financial exposure regardless of resale performance. Diamonds are best purchased to be worn and enjoyed, not as assets.
Do lab grown diamonds come with a certificate? Yes. Lab grown diamonds are certified by the same gemological laboratories as mined stones — primarily IGI and GIA — and graded on the same Four Cs criteria (cut, color, clarity, and carat weight). You can find more answers to common questions in our FAQ.
Ready to see them for yourself? Explore our loose lab grown diamonds — or learn more about how they're made, whether they're real, and how they compare to mined stones.
