Choosing a diamond can feel intimidating. Yet its quality rests on four universal criteria known as the “4Cs”: Carat (weight), Colour, Clarity and Cut. Understanding these four words lets you compare two stones with confidence and put your budget where it truly matters.
1. Carat: weight, not size
Carat measures a diamond's weight (1 carat = 0.2 grams), not its dimensions. Two diamonds of equal carat can look quite different depending on their cut: a well-proportioned stone often appears larger than a heavier but poorly cut one. Prices jump at “round” weights (1 ct, 2 ct), so choosing 0.90 ct over 1.00 ct gives you a near-identical look to the eye for a noticeably lower price.
2. Colour: aiming for colourless
A white diamond's colour is graded from D (perfectly colourless) to Z (visible yellow tint). The differences between neighbouring grades are subtle and often invisible once the stone is set. For an excellent balance of visual purity and budget, grades D to G are considered colourless, while H to J remain superb — especially on a yellow or rose gold setting that masks any slight warmth.
3. Clarity: natural inclusions
Almost every natural diamond carries tiny marks formed during its creation, called inclusions. The scale runs from FL (flawless) to I (inclusions visible to the naked eye). The good news: from the VS (Very Slightly included) grade upward, inclusions are only visible under 10x magnification and have no effect on sparkle. Aiming for VS1–VS2, or an “eye-clean” SI1, is the smartest choice for most budgets.
4. Cut: the most important C
Cut is the only C shaped by human hands, and it is by far the most decisive for a diamond's beauty. It describes the precision of the facets and proportions, which govern how light enters, bounces and returns from the stone. An Excellent or Very Good cut makes a diamond truly sparkle; a poor cut dulls even the purest stone. If you must prioritise a single criterion, choose cut.
Finding the right balance
An IGI-certified diamond comes with an independent report detailing its 4Cs — a guarantee of transparency. Our recommendation for a brilliant solitaire without overspending:
- Cut: Excellent or Very Good, the absolute priority.
- Colour: D to G for white gold; H to J for yellow or rose gold.
- Clarity: VS1 to SI1, eye-clean.
- Carat: a weight just under the round thresholds (0.90; 1.90 ct).
At Maison d'Éclat, every engagement ring is composed to order: you choose the metal, the weight and the stone's characteristics, then we prepare your quote. Explore our designs and begin your project whenever you are ready.