Buying guidance

Beyond the four Cs: comparing loose diamonds

A useful shortlist combines grading information with the practical requirements of the piece you are manufacturing or sourcing.

Read dimensions alongside carat weight

Carat is a measure of weight, not face-up size. Compare length, width and depth when evaluating proportions or matching a stone to a setting.

Color and clarity grades help narrow the field. Media, inspection and the intended setting still matter.

Confirm the exact stone, report, current availability and commercial conditions. Keep a written record of the specifications and terms.

Reviewed by Only Carat editorial team. Updated 2026-10-23.