Choosing a solitaire: the 4Cs without the jargon

A solitaire is a single diamond, so the stone does all the work. The 4Cs describe its qualities. Here's what each one means in practice.

Cut

Cut is how well the diamond has been shaped and polished, and it affects sparkle more than anything else. If you prioritise one C, make it cut.

Colour

White diamonds are graded on how colourless they are. The difference between neighbouring grades is very hard to see once the stone is set, especially in yellow or rose gold.

Clarity

Clarity describes tiny natural inclusions. Many diamonds have inclusions you can't see without magnification. 'Eye-clean' is what matters for a ring you'll wear.

Carat

Carat is weight, not size. Two stones of the same weight can look different depending on their cut and shape. A stone just under a round number, say 0.9 ct instead of 1 ct, can look almost identical.

Shape and setting

• Round brilliants give the most sparkle; ovals and pears can look larger for their weight.
• A halo of small diamonds makes the centre stone appear bigger.
• Platinum or white gold suits a whiter stone; yellow or rose gold adds warmth.
• Ask about the grading report for any stone, and what it covers.

The best way to choose is side by side. We'll put a shortlist on the tray at the house, or under the camera on a live video call.