Engagement guide

Choosing a stone: what to look for, in plain words

Cut, colour, clarity and carat, explained the way we explain them across the salon table, plus when a coloured stone makes more sense.

Loose champagne and white diamonds on a grey sorting tray

Most people arrive having read about the four Cs and leave having chosen with their eyes. Both matter. Here is how I explain them when we sit down with a tray.

Cut is the one to spend on

Cut decides how a diamond handles light. A well-cut stone looks bright from across a room and lively up close; a poorly cut one looks glassy however large it is. For round stones there is a grade to guide you. For ovals, cushions and emerald cuts, there isn’t, which is why we look at them together in daylight before anything else.

Colour and clarity, in proportion

  • Colour runs from D (no colour) downwards. In yellow or rose gold, a G or H looks just as white once set, and costs noticeably less.
  • Clarity describes tiny inclusions. From VS2 upwards, you won’t see them without a loupe.
  • Champagne diamonds are a natural colour, not a lower grade. They suit warm gold and cost less than white stones of the same size.

Carat is size, not quality

Two stones of the same weight can look quite different in size, depending on how they were cut. An oval of 0.9 ct can look as large as a round of 1.1 ct. We show you stones by how they look on the hand, not by the number on the report.

Choose the stone that makes you look twice. Then check the report.

Sapphires and spinels

For a coloured engagement ring, sapphire is hard enough for daily wear and comes in more colours than blue. Spinel is a little softer and often brighter. Both are traced to the mine in the same way as our diamonds.

Every diamond of 0.5 ct or more comes with an independent grading report, and every stone we sell can be traced to its mine and cutter. If you’d like to see a selection, tell us your rough budget when you book and I’ll prepare a tray.

More from the guide

The full guide
  • Three plain rings in yellow gold, rose gold and platinum side by side

    Engagement guide

    Gold or platinum? How each metal wears

    Yellow, rose and white gold, and platinum: how they look, how they wear over decades, and what each costs to keep.

  • A hand trying on a plain gold sizing ring from a small tray of rings

    Engagement guide

    Finding the ring size, quietly

    How to find a ring size without giving the game away, what the size numbers mean, and what happens if you get it wrong.

Talk it through in person

An hour in the salon with one of our jewellers. Tea is always on.

Chat on WhatsApp

Cookie preferences

Cookie policy