Aug 252013

A quick post about calculating diamond depth in a round diamond.

If you have a diamonds measurements, you can calculate the total depth of the diamond.  The total depth is a quick guide to ensure the diamond is ‘OK’.

To calculate the depth you divide the depth by the average of the  the minimum & maximum diameter.  The weight of the diamond does not have any impact.  The formula is the same for a 0.25ct diamond or a 50.00ct diamond.  Lets do a couple:

Measurements: 6.20 – 6.30 x 4.10

Depth / Average Diamater * 100

4.10 / 6.25 * 100 = 65.6% total depth   <- This diamond is quite deep and will not score a very high cut grade.


Measurements: 6.72 x 6.75 x 4.07

4.07 / 6.735 * 100 = 60.4% total depth <- This diamond has the potential to be very attractive.


That’s it!  This is for round diamonds, other shapes use different formulas.

  One Response to “Calculating Diamond Depth (round diamond)”

  1. […] you calculate the diamond depth, you get 75.2%.  This is mind blowing to a diamond guy like me.  A true first!  No problem, just […]

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