Reading Diamond Certs :: Proportions

The Proportions can make an enormous difference in the appearance of a diamond.

On a GIAGTL certificate, “Proportion” is a general heading that includes the Depth % and Table % and various other details as described in our other lessons.


All of the top three labs now include a Cut Grade, which is an overall analysis of a diamond’s cut — the most important factor in the beauty of a diamond.

The cut grade is the most valuable piece of data for you, the consumer. It summarizes the real beauty of a diamond, from an expert’s eye. This is so much more accurate than guessing the beauty of a stone from the individual stats, which is all we have ever been able to to up to this point. Use the Cut Grade — it’s important.

Proportions, Polish, and Symmetry are actually more important than ColorClarity or Carat weight in determining beauty.

Keep in mind that beauty is in the eye of the beholder, and everyone does NOT have exactly the same preferences in diamond proportions. Some people prefer a table that is a little wider (within reason) to make the diamond appear larger and brighter, while others like a smaller table because it may add a little more fire.

Please Note:

Discounts for stones outside of these limits are too difficult to explain here. If you want to learn how to calculate a price for any diamond you want, please see my easy, fast, step-by-step Diamond Pricing Tutorial page.

NEXT :: Diamond Certificates :: Symmetry

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