By eye, by loupe, by tester: can a lab-grown diamond be recognised? What jewellers and machines see — and don't see.

Let's start with the answer everyone expects: no, nobody can tell a lab-grown diamond from a natural one with the naked eye. Not you, not a jeweller, not an expert. Same sparkle, same fire, same scintillation — since it is the same material, cut by the same hands to the same proportions.
The jeweller's 10× loupe reveals inclusions, cut quality, facet edges — but nothing that betrays origin. A lab-grown diamond's inclusions look like a natural one's. An honest professional will tell you: under the loupe, they grade the stone, they don't guess its provenance.
The classic electronic tester, which measures thermal conductivity, identifies a lab-grown diamond without hesitation as a diamond — logically, since that is what it is. It is in fact the test that instantly separates it from imitations like cubic zirconia.
Only gemmological laboratories equipped with specialised instruments — spectroscopy, fluorescence imaging, analysis of the crystal's growth patterns — identify a stone's origin with certainty. These machines read the history of the diamond's growth, not its quality. That is why the industry rests on a simple principle: the declaration of origin, carried by the certificate and the girdle's laser inscription.
At MICKAEL STONE, the question does not arise: we use only lab-grown diamonds, and we write it everywhere. Origin is not a secret to be detected — it is a choice we claim.
Not visually. They can read the girdle's laser inscription under a loupe if the stone is certified — the only 'detection' available in a shop.
Do testers sold online detect origin?No. They separate diamond from imitations, not laboratory from natural.
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