By GrownDiamond Editorial TeamUpdated March 17, 20265 min read
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Are Lab-Grown Diamonds Real Diamonds?

A

Quick Answer

Are lab-grown diamonds real diamonds?

Yes, unequivocally. Lab-grown diamonds are 100% real diamonds — chemically (pure carbon), physically (hardness 10, density 3.51 g/cm³), and optically (refractive index 2.42) identical to natural diamonds. The FTC, GIA, and IGI all recognize lab diamonds as real diamonds.

📊 The FTC's 2018 Jewelry Guides update specifically defines diamonds as including 'laboratory-created diamonds' that have the same optical, physical, and chemical properties as mined diamonds.

The Scientific Evidence

The "realness" of a diamond is defined by its physical and chemical properties. Here's why lab diamonds are, by every scientific measure, real diamonds:

PropertyLab DiamondNatural DiamondMatch?
Chemical compositionPure carbon (C)Pure carbon (C)Identical
Crystal structureCubic (diamond cubic)Cubic (diamond cubic)Identical
Hardness (Mohs)1010Identical
Density3.51–3.53 g/cm³3.51–3.53 g/cm³Identical
Refractive index2.422.42Identical
Thermal conductivitySameSameIdentical
Optical dispersion0.0440.044Identical
Passes diamond testerYesYesIdentical

The US Federal Trade Commission (FTC) is the governing body for jewelry marketing standards in the United States. In 2018, the FTC:

  • Removed the word "natural" from the definition of "diamond," making lab diamonds legally equivalent
  • Required disclosure that lab diamonds must be called "lab-grown," "lab-created," or "man-made" — but NOT "simulated" or "imitation"
  • Confirmed that lab diamonds have the same optical, physical, and chemical properties as mined diamonds

Lab Diamonds vs "Fake" Diamonds

Confusion often arises from conflating lab diamonds with diamond simulants like moissanite or cubic zirconia. These are fundamentally different:

  • Lab diamond: Pure carbon, cubic crystal structure = REAL DIAMOND
  • Moissanite: Silicon carbide — a different mineral. NOT a diamond.
  • Cubic Zirconia (CZ): Zirconium dioxide — yet another mineral. NOT a diamond.

Lab diamonds pass standard diamond testers (thermal conductivity probes) because they genuinely have diamond-level thermal conductivity. Moissanite also passes standard testers (for a different reason). CZ does not pass.

Shop Real Lab Diamonds

GIA and IGI certified — the same credentials as natural diamonds.

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Frequently Asked Questions

Yes. Professional jewelers and gemologists recognize lab-grown diamonds as real diamonds. The Gemological Institute of America (GIA), the world's most respected diamond authority, certifies lab diamonds with the same grading reports as natural diamonds.