Earrings · 3 min read · Published , updated
How we match a pair of diamonds
Diamond earrings only look right when the two stones look identical. Here are the exact rules our matching follows.
Most diamonds are sold one at a time, so a pair has to be found. We compare live, independently graded natural diamonds and only offer two stones together when they pass every one of these rules:
- Same shape, same grading lab and the same cut grade.
- The same colour grade. Colour is the difference the eye notices first side by side, so it must match exactly.
- Clarity no more than one grade apart. At earring distance a single clarity grade is not visible.
- Carat weight within 0.05 ct, and face-up length and width each within 0.05 mm, so the two stones look the same size on the ear.
- Depth within 1.5% and table within 2%, so they sparkle the same way.
Each pair is given a match score out of 100, where 100 means identical on every measured point. We only show pairs scoring 90 or more. Because the diamonds are live, a pair can sell; if one stone goes, we show you the closest new partner for the one that remains.
Fluorescence is not used for matching: at the strengths found in fine diamonds it does not change how a pair looks in everyday light.
