The 4Cs of diamonds: the simple guide to choosing well
Carat, Color, Clarity, Cut: understand the 4Cs in five minutes to choose a diamond — lab-grown or not — without getting it wrong.
Four letters that say it all
Since the 1950s, every diamond in the world — mined or lab-grown — has been assessed on four criteria: Carat, Color, Clarity, Cut. Understanding them means knowing how to read a certificate and buying with full knowledge. Here is the essential, without jargon.
Carat: the weight, not the size
The carat measures the stone's weight: 1 carat = 0.20 grams. Two one-carat stones can look different depending on their cut and proportions. Above all, remember that prices jump at 'round' carat marks (0.50 – 1.00 – 1.50…): just below the mark, the stone looks identical and costs noticeably less.
Color: from icy white to warm white
Colour is graded from D (perfectly colourless) to Z (tinted). To the eye, the difference between a D and a G is almost imperceptible once the stone is set. Lab-grown diamonds regularly reach the D-E-F grades that were once extremely rare.
Clarity: the purity
Clarity describes internal inclusions, from FL/IF (none visible at 10× magnification) to I (visible to the eye). The good benchmark: from VS2 up, inclusions are invisible to the naked eye. Paying for better is about the certificate, not the gaze.
Cut: the criterion that makes the light
The cut is the only criterion owed to the human hand — and it is the most important for brilliance. A perfectly cut stone returns the light; a badly proportioned one extinguishes it, whatever its other grades. Never compromise on cut.
At MICKAEL STONE, we select our lab-grown diamonds first on cut and whiteness — because that is what your eye will see every day.
Frequently asked questions
A fine cut (Excellent/Very Good), a colour from D to G, a VS clarity: the eye won't see better, the budget will.
Do the 4Cs apply to lab-grown diamonds?Yes, in exactly the same way, by the same laboratories (IGI, GIA).
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