Cut Diamond Grade Categories

You can fit cut diamonds into one of five categories. Not renowned for my tact, I simply call them Best, Better, Good, Junk, and Garbage. Granted, retailers use more euphemistic terms. However, they remain undefined. But, never mind what they’re called. By the time we finish, we’ll dispense entirely with all such subjective terms and be able to assign two precise, objective numbers to any stone. These numbers will have a universal meaning. They will transcend all previous subjective designations and will be unambiguous.

How to Read Between the Lines of Certificates

First, consider the present situation. Take the information supplied by sellers and required by truth-in-advertising laws. If you know how, you can read between the lines of their certificates.

Here is how, starting from the bottom up.

  • If the stone is set in a mounting and sold without a certificate of any kind, rest assured it would grade either as Junk or Garbage.
  • If the stone is sold with a grading report or certificate, READ IT. In its simplest form, you should still see notations relative to the diamond’s weight, color, and clarity, as well as numerical values for its diameter