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A practical guide to the 4Cs

Use cut, color, clarity, and carat as a shared language, then judge the whole stone.

Cut directs the light

Cut describes proportion and finish rather than outline. It has the strongest visible effect on brightness and contrast.

Round brilliants carry a cut grade. Fancy shapes are judged on their polish, symmetry, and measured proportions instead, which is why we publish the full measurement set rather than a single grade.

Color is a range

Color grades describe how little body color a stone shows under controlled grading conditions. Metal color, shape, and setting can change what you notice.

A near-colorless stone set in yellow gold usually reads as white. The same stone beside platinum is judged against a cooler reference, so the grade matters more the cooler the setting.

Clarity is inspected, then interpreted

Clarity grades record internal and external characteristics under magnification. A grade does not replace an eye-clean review of the specific stone.

Position matters as much as the grade. A characteristic under a prong behaves differently from one under the table, and the plot on the report shows you which you have.

Carat is weight

Two stones with the same carat weight can face up differently. We show millimeter measurements so scale is not reduced to one number.

Judge the whole stone

The four grades narrow a search. They do not rank two finished stones against each other, and they say nothing about how a piece will look on a hand.

  • Start with cut quality and measured spread, then adjust color and clarity to fit the budget.
  • Compare millimeter dimensions before carat weight when scale is the priority.
  • Read the report comments, not only the grade boxes.
  • Ask for the stone to be reviewed unmagnified before it is set.
Last reviewed for product structure on September 27, 2026.
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