Melee sizing reference

MM size & carat weight chart

Round-brilliant nominal mm to approximate single-stone carat weight. Use as a planning tool — every parcel ships with a written QC sheet listing the actual average.

Round brilliant — by mm

mmApprox. ct (each)Stones per carat
0.800.003330
1.000.005200
1.200.009115
1.500.01567
1.700.02050
2.000.03033
2.200.04025
2.500.06017
2.700.08013
3.000.10010
3.250.1407
3.500.1706
4.000.2504
4.500.3603
5.000.5002

Tolerance & sorting

Published mm is the nominal sieve size. Our acceptance window is ±0.02mm. Stones outside the window are pulled and graded into the next sieve up or down — they never ship in the original parcel.

Fancy shapes

For princess, baguette, marquise, pear, oval, and emerald shapes — request a per-shape chart from the sales desk. Length × width × depth tolerances differ from round and from each other; we publish them per cutting partner.