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Natural Diamond vs Lab-Grown Diamond: How to Tell Them Apart?

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Since 2018, lab-grown diamonds have flooded the market at prices 5 to 10 times lower than natural diamonds. If you recently purchased a diamond at an unusually low price, or wish to sell a diamond whose origin you are unsure of, this guide is for you.

What is a lab-grown diamond?

A lab-grown diamond (also called synthetic diamond, CVD or HPHT) is chemically identical to a natural diamond: carbon crystallized in a cubic structure. The fundamental difference lies in its origin: one formed billions of years ago in the Earth's mantle, the other was created in a few weeks in an industrial reactor.

How to tell them apart? What you can do

With the naked eye, it is impossible. Even with a loupe, the two stones are indistinguishable. Here is what you can check yourself:

  • The certificate: a GIA or IGI certificate explicitly mentions « Natural » or « Laboratory Grown ». This is the simplest method. Look in your paperwork.
  • The purchase price: if you paid less than 2,000 € for a diamond over 1 carat after 2018, it is very likely a lab-grown diamond.
  • The seller: high-end jewelry stores (Cartier, Van Cleef…) only sell natural diamonds. Online jewelry stores with discounted prices often sell lab-grown.

What only a gemologist can do

Certain distinction requires specific equipment that only professionals have:

  • DiamondView (De Beers): emits a characteristic luminescence that differs according to origin
  • Infrared spectrometer (FTIR): detects impurities specific to natural diamonds
  • Diamond Sure / Diamond View: sorting devices used by professional dealers

At Diamantaires Paris OG, our GIA-certified gemologists have these devices and can analyze your stone in a few minutes.

What resale value in 2026?

Type of diamondTypical purchase price (1ct G VS1)Resale value
Natural diamond5,000 – 8,000 €3,000 – 5,500 €
Lab-grown diamond500 – 1,200 €50 – 200 €

Lab-grown diamonds have lost 80 to 95% of their resale value in a few years. Industrial overproduction has collapsed their prices on the secondary market. We do not purchase lab-grown diamonds because there is virtually no secondary market for them.

Frequently asked questions

Can a Cartier jewelry piece contain a lab-grown diamond?

No. Major houses like Cartier, Van Cleef & Arpels, Boucheron, or Bulgari only use certified natural diamonds. If your piece is authentic and signed, the diamond is natural.

Is my diamond without a certificate necessarily lab-grown?

No. Many old natural diamonds have never been certified. GIA certification has only existed since the 1950s. A family diamond without a certificate can perfectly be a very beautiful natural diamond — our gemologists can evaluate it on-site.

How to know before coming?

Send us a photo of your diamond and its certificate (if any) at [email protected]. We will respond within 24 hours with an initial evaluation.

Have your diamond analyzed for free

You don't know if your diamond is natural? Our GIA-certified gemologists analyze it in minutes. Free expertise, no obligation, completely confidential.

43 Rue Beaubourg, 75003 Paris

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