Laboratory-Grown vs. Natural Diamonds: What's the Same and What's Different

The short answer: A laboratory-grown diamond and a natural (mined) diamond are the same material: carbon crystallized in the cubic crystal system, with the same hardness and optical properties. The difference is origin. One formed in the earth, and the other was grown in a factory in a matter of weeks. You can't tell them apart by eye. Gemological laboratories identify origin with specialized instruments and state it on the grading report. In the U.S., the Federal Trade Commission's Jewelry Guides require sellers to disclose that a diamond is laboratory-grown, which is why every stone we sell is described that way.

What's the same

The FTC's Jewelry Guides define a diamond by what it is, not where it came from. Under 16 CFR 23.12, "a diamond is a mineral consisting essentially of pure carbon crystallized in the isometric system." The definition goes on to list a hardness of 10, a specific gravity of about 3.52 and a refractive index of 2.42. A laboratory-grown diamond meets that definition.

GIA, the Gemological Institute of America, says the same thing from a scientific angle. Although laboratory-grown diamonds are made in factories, "their chemical and physical properties correspond very closely to that of natural diamonds." GIA also points out that calling laboratory-grown diamonds "imitations or simulants" is incorrect.

In practice this means:

  • Durability: the same hardness, so a laboratory-grown diamond is suited to everyday wear in the same way.
  • Optics: the same refractive index, so a well-cut laboratory-grown diamond shows brilliance and fire the same way.
  • Grading: labs such as IGI grade laboratory-grown diamonds for carat, color, clarity and cut, and most of our stones carry IGI reports.

What's different

Origin and time

Natural diamonds formed deep in the earth and were carried toward the surface by volcanic eruptions, which created the rock formations known as kimberlite pipes (GIA). Laboratory-grown diamonds are grown by one of two methods. HPHT uses a press that recreates high pressure and temperature, and GIA says crystals form over days to weeks. CVD deposits carbon from a gas onto a seed in a vacuum chamber, and GIA says a batch can take three or four weeks. We explain both in our guide to CVD vs HPHT.

Scientists first grew diamonds in a laboratory in the mid-1950s, but those were too small for jewelry. According to GIA, production of larger, gem-quality crystals began in the mid-1990s.

How they're identified

Because the material is the same, you can't separate them by looking. Laboratories rely on growth features. Natural, HPHT-grown and CVD-grown diamonds grow in different crystal shapes and leave different internal patterns. GIA uses a fluorescence imaging instrument (the DiamondView) that shows concentric growth patterns in natural diamonds, cross-shaped patterns in HPHT-grown stones and striations in CVD-grown stones. Other clues include strain patterns, fluorescence and, in HPHT stones, metallic flux inclusions.

For a buyer, this means the grading report is the reliable record of origin. Our guide to IGI certification explains how to read and verify one. IGI states that every laboratory-grown diamond it reports on is laser-inscribed with an "LG" prefix before the report number. GIA inscribes its current laboratory-grown assessments with the words "Laboratory-Grown" and the assessment number, as National Jeweler reported.

Treatment

Post-growth treatment is common in laboratory-grown diamonds. GIA notes that many CVD crystals are heat-treated to remove a brownish tint, and that some colors (pink and red, for example) come from post-growth processes. Natural diamonds can be treated too. Either way, a reputable lab report discloses what the lab detects, so read the comments section.

Price and value

Laboratory-grown diamonds generally cost less than natural diamonds of similar size and grades, which is a big part of why buyers choose them. Prices for both change over time. We don't make resale or investment claims about any diamond, laboratory-grown or mined. Choose the stone because you like it and the price makes sense to you today.

What the FTC says about the words

The FTC's Jewelry Guides are the U.S. guidance on how gems and jewelry may be described. The Guides were last revised in 2018. Here's what they mean for the words you'll see:

  • "Laboratory-grown", "laboratory-created" and "[manufacturer name]-created" are the FTC's examples of clear disclosures that a stone is not mined. We use laboratory-grown (or the short form lab-grown) on every listing.
  • "Cultured" may be used for laboratory-created diamonds only if it is qualified by a clear, conspicuous disclosure that the product is not a mined stone (16 CFR 23.12(c)(3)). The FTC's 2018 notice explained that the qualifier doesn't always have to sit directly next to the word, as long as the disclosure is clear.
  • "Synthetic" was removed from the FTC's list of suggested descriptors in 2018 but not banned. As JCK reported, the FTC also cautioned marketers against using words like "real", "genuine", "natural" or "synthetic" to imply that a laboratory-grown diamond is not actually a diamond.
  • Imitations are a different thing. Under 23.25, words like "gem" or "stone" for laboratory-made or imitation products must be qualified with a term such as "laboratory-grown", "imitation" or "simulated", so the buyer knows what the product is.

The bottom line: a laboratory-grown diamond is a diamond, and an honest seller tells you plainly that it was grown in a lab.

Lab-grown diamonds vs. simulants

It's easy to lump these together, but they're different materials. GIA explains that imitations such as cubic zirconia and synthetic moissanite only look like diamond and have "very different chemical and physical properties" that trained gemologists can identify easily. A laboratory-grown diamond is diamond, which is why it takes laboratory testing to separate it from a mined one.

How to decide

Ask yourself:

  1. Does origin matter to you? If a stone formed in the earth is important to you, choose natural. If what matters is the material, the look and the specification for your budget, laboratory-grown is a reasonable choice.
  2. Which grades will you actually see? Cut quality drives sparkle. Color and clarity differences at the top of the scale can be hard to see once a stone is set, so compare stones in the video before paying for grades you can't see.
  3. Can you verify it? Buy a stone with an independent report, check the report number on the lab's website, and make sure the measurements and grades match the listing.

Shopping laboratory-grown diamonds with us

Every stone we list is a laboratory-grown diamond, identified as such in the title, with a link to its IGI or GIA report. Most listings also include a 360° video. Start with white diamonds or a shape such as round, or explore color in our fancy-color collection. You can also browse by size, for example 1 to 1.99 carats or 2 to 2.99 carats. Our FAQ covers the 4Cs and report verification.

Related reading: IGI-Certified Lab-Grown Diamonds: What IGI Certification Means and How to Verify a Report · CVD vs HPHT Lab-Grown Diamonds: How They're Made and Whether It Matters

FAQ

Is a laboratory-grown diamond a real diamond? Yes. It meets the FTC's definition of diamond (pure carbon crystallized in the isometric system). The FTC requires the laboratory-grown origin to be disclosed.

Can a jeweler tell the difference just by looking? No. Separating laboratory-grown from mined diamonds requires laboratory instruments. The grading report and the laser inscription on the girdle are the practical records of origin.

Is "lab-created" the same as "lab-grown"? Yes. The FTC lists "laboratory-created" and "laboratory-grown" as examples of disclosures that a diamond is not mined.

Is moissanite a lab-grown diamond? No. Moissanite is a different material (silicon carbide) that imitates diamond. GIA classes it with simulants, along with cubic zirconia.

Are lab-grown diamonds graded the same way as natural diamonds? IGI grades laboratory-grown diamonds for carat, color, clarity and cut. Since October 1, 2025, GIA describes new colorless to near-colorless laboratory-grown stones as "Premium" or "Standard" instead of using its natural-diamond color and clarity grades.

Will a lab-grown diamond hold its value? We don't make resale or investment promises for any diamond. Buy the stone you love at a price that makes sense to you today.

Sources

Reviewed September 2026 against the sources above. The FTC Guides are guidance, not a substitute for legal advice.

Back to blog