Why Fancy Shapes Don't Get a Cut Grade

Grading reports give round brilliants an overall cut grade, but not ovals, pears or marquises. Here is why, and what to look at instead.

If you compare two diamond reports, one for a round stone, one for a marquise, you will notice something missing on the second. There is no overall cut grade.

Clients often read this as an omission, or worse, as a sign the stone is inferior. It is neither.

The reason is honest

Round brilliants are standardised. The proportions that make one perform well are known, measurable and consistent, which makes it possible to grade cut on a single scale that means the same thing every time.

Fancy shapes are not standardised. A marquise can be cut long or wide, deep or shallow, with different facet arrangements, and several of those variations are legitimately beautiful. Light behaves differently in each. A single grading scale applied across all of them would produce a number that sounded authoritative and told you very little.

Rather than invent a grade that would not survive scrutiny, the report leaves it out.

What the report does tell you

Polish, how cleanly the facet surfaces were finished.

Symmetry, how precisely the facets were aligned and the outline balanced.

Both are graded, both are meaningful, and on a fancy shape they are the two craftsmanship measures you have.

What you have to do yourself

Look at the stone.

Face up, at arm's length, under ordinary light rather than the spotlights over a display case. Check that the outline is even. Check that the two halves mirror each other. Check where the dark areas fall when you tilt it.

For a fancy shape, your eye is not a fallback for the certificate. It is the primary instrument, and the certificate supports it.

Book a complimentary design consultation at our Kuala Lumpur atelier: 010-766 7448 · hq@cgarden.com.my

C'Garden is an independent bespoke jeweller in Kuala Lumpur. We are not affiliated with, endorsed by, sponsored by or certified by any organisation, laboratory or brand named in this article. Third-party names are used only to refer factually to those organisations and their published standards. All text and imagery in this article is original work created by C'Garden.

Reference

Gemological Institute of America. (2024). Observations of oval-, pear-, and marquise-shaped diamonds: Implications for fancy cut grading. Gems & Gemology. https://www.gia.edu/gems-gemology/fall-2024-fancy-shaped-diamonds