Carat is weight. Millimeters are what your ring head, prong seat and earring post actually fit. Order by mm and you will avoid the number-one return reason: the stone does not fit the setting.
Round brilliant reference sizes
| Carat | Diameter (mm) |
|---|---|
| 0.5 | 5.0 |
| 1.0 | 6.5 |
| 1.5 | 7.4 |
| 2.0 | 8.1 |
| 3.0 | 9.3 |
| 5.0 | 11.0 |
Fancy shapes reference (length x width)
| Shape | 1 ct (mm) | 2 ct (mm) | 3 ct (mm) |
|---|---|---|---|
| Oval | 8.0 x 6.0 | 10.0 x 7.0 | 11.5 x 8.0 |
| Pear | 7.5 x 5.5 | 9.5 x 6.5 | - |
| Marquise | 10.0 x 5.0 | 13.0 x 6.0 | - |
| Emerald | 7.0 x 5.0 | 8.5 x 6.0 | 10.0 x 7.0 |
| Cushion | 6.5 x 6.5 | 8.0 x 8.0 | 9.5 x 9.5 |
| Princess | 5.5 x 5.5 | 7.0 x 7.0 | - |
| Radiant | 6.5 x 5.0 | 8.0 x 6.0 | - |
Actual sizes vary a little with cut proportions, which is why the measured mm on the GRA certificate is the number to trust. If your setting needs a non-standard size, ask - we cut to order.