How to Judge Diamond Clarity

Diamond clarity is graded on an 11-point scale, 12 for some grading systems. A correct clarity grading requires thorough inspection of the diamond under a loupe or microscope, magnifying the diamond by a power of 10x. An expert will look for scratches, polishing lines, extra facets, pinpoints, bearding, feathers, crystals, clouds, carbon, chips, and even fractures.

As fascinating as a full description of a diamond can be—it does, after all, prove a natural diamond’s uniqueness—the full description can feel overwhelming. After all, most diamond wearers are more interested in how the diamond looks to the unaided eyes of other people, not the exact diamond clarity grade.

And most diamond wearers are not looking for a flawless diamond. (They certainly don’t want to pay for flawless diamonds!) They are looking for affordable diamonds with no obvious visual defects. They expect hundreds of friends and relatives to gaze at the diamond—and unless some of those are jewelers or gemologists, they aren’t likely to whip out a loupe for an in-depth diamond clarity inspection.

Judge Diamond Clarity Yourself

And what is the best way to find a diamond with no obvious visual defects? Look at diamonds and judge for yourself. Resist the temptation to read the diamond certificate first. Start with a loose diamond. Look down at it, through the table. Look through the sides from every direction. Even look from the diamond’s bottom, upward through the pavilion.

If you can see inclusions or blemishes, the diamond is a grade I-1 or lower. And if you can see even the smallest problem with the diamond, so can the people to whom you plan to show it.

Next, borrow a 10x loupe from a jeweler. If any of the diamond’s inclusions appear larger than a grain of salt, or if you can see cracks or black spots, the diamond is clarity grade SI-1 or lower.

Alternatively, if your inspection with a 10x loupe reveals nothing wrong with the diamond, and you feel you’ve given it a thorough review—top, bottom, all the sides—it is likely a VS-2 grade or higher. The GIA defines the VS-2 as “The diamond contains minute inclusions such as small crystals, clouds or feathers when observed with effort under 10x magnification.” If you are a novice, not a trained gemologist, it makes sense to assume an expert may discover “minute inclusions” even if you didn’t discover any.

While VS-2 is only the sixth clarity grade from the top, about 36% of the loose diamonds available online and through retailers are graded VS-2 or the slightly higher grade VS-1. This grade range is very popular—an untrained observer with a 10x loupe might not see anything wrong with these diamonds, and they are priced significantly better than the rare diamonds with flawless clarity.