Clarity

Diamonds were formed deep within the earth under extreme heat and pressure so often - even usually - contain unique birthmarks, internally (inclusions) and/or externally (blemishes). The term diamond clarity refers to the absence or density of these inclusions and blemishes.

The GIA’s clarity chart looks like this:

From a practical and budget point of view, most buyers wish to avoid seeing any inclusions or blemishes but are ok finding some under magnification.

To give you a visual sense of how clarity can be imagined, take a glass of water, at any color level you want, add grains of salt, or pepper, and call them inclusions.

Just as in a diamond, some inclusions will be white or so small you could have dozens and they would be invisible to the eye, while, in another stone, just one small, carefully placed black bit is easily seen.

So grading clarity is pretty subjective. Unless you want to become a gemologist or buy a particular grade for some reason, we offer an easy solution to picking clarity. Buy at the point farthest down the scale where you can’t find an inclusion with your eye. That’s ‘eye clean’ in gem jargon.

Here’s a rough guide to show which clarities are likely to be eye clean in different cuts:

For beautifully cut round brilliants (and other cuts based on the brilliant such as pears, ovals, cushions, hearts, marquise, princess and radiants) where the amount of light dispersion baffles the eye, consider buying these clarities (if given by rigorous gia certification).
- - A very occasional SI-2 where there are lots of tiny inclusions rather than a few big ones.
- - Most carefully chosen SI-1 stones.
- - Almost all VS-2 stones.
- - Practically all VS-1 stones.
Step-cut stones like emerald cut and asscher cut, because they have less facets, are more ‘open’ to the eye. This means it’s usually (but not always) necessary to go a grade or two higher if you don’t want to see any inclusions.
- - Consider buying.
- - A very occasional SI-1.
- - Most carefully chosen VS-2S.
- - Almost all VS-1S.
- - Practically all VVS-2S.

To get exactly the right ‘eye clean’ stone, either online or in-store, we can help you. If you’re buying online, we suggest going to our help section to speak with one of our diamond specialists who will get back to you after ensuring which stones pass their eye clean test (and they have great eyes!).

If you’d like to personally examine and compare several stones under a microscope yourself, click on our 'free hotel offer'. Come to any of our galleries, by appointment, and we’ll help you locate the inclusions with your own eyes in a selection of stones brought in especially for you. Then, taking the stones out of the scope, knowing exactly where those inclusions are, try hard to find them using no magnification.

If you can’t find them, save the money. At that level they don’t impact in any human-eye detectable way on the stone’s brilliance. And, since you’re not likely to walk around with a diamond-scope on your arm, your stone has passed the relevant eye-clean test.

Finally, remember every grade you can go down without crossing the eye-clean barrier saves you serious money.