Clarity · Chapter 11

Clarity, without overbuying

What the laboratory records, what the eye notices, and when an inclusion deserves a structural check.

Clarity becomes much easier to use when magnification, face-up appearance, and durability are treated as three different questions.

The scale is a laboratory judgment

Clarity runs from Flawless to Included and is assessed under controlled conditions at 10× magnification. Neighboring grades can differ under a loupe while looking identical to an unaided eye.

“Eye-clean” needs a definition

Eye-clean is useful shopping language, but it is not a laboratory grade. FL, IF, and VVS stones are ordinarily clean to the unaided eye and often cost more for rarity that cannot be seen. VS1 and VS2 are commonly eye-clean at a normal viewing distance. SI1 can be eye-clean depending on inclusion type and location; SI2 and Included grades need more careful exact-stone inspection. None of these is a guarantee—stone size, lighting, angle, eyesight, and the setting can change the answer.

Position and relief shape visibility

A dark crystal beneath the table may draw attention more readily than a pale inclusion near the edge. Reflections can also make one characteristic appear in several places even when the plot shows it once.

Size and shape change the answer

A clarity grade describes the stone under magnification; whether you can see an inclusion also depends on the stone’s size and cut. Larger stones present larger tables and larger features, so a VS2 that is invisible in a one-carat round may be visible in a three-carat stone. Brilliant cuts break up light and help hide small features; the open facets of emerald and Asscher cuts show them more plainly. For VS2 and below, judge eye-cleanliness in the exact shape and size you are considering.

Worth remembering: The same grade can be invisible in one stone and visible in another.

Durability is a separate question

A surface-reaching feather, cavity, very thin girdle area, or feature near a vulnerable point may deserve professional review. The inclusion name alone does not establish risk; its size, position, orientation, and setting all matter.

Transparency is not captured by the label alone

Clouds, graining, and dense groups of features can sometimes affect how crisp or transparent a diamond appears. Read the comments and request slow, neutral imagery rather than relying on the plot’s apparent busyness.

Worth remembering: Choose for visible appearance and sound structure—not for the rarity of a label you cannot see.

When the report says clouds are not shown

The comment means clouds are present but were not drawn on the plot. The grade already accounts for them, and at higher clarity grades they rarely change appearance. At SI grades, or in larger stones, several clouds together can soften transparency, so ask for exact-stone video in even, daylight-like light and look for crisp, well-defined facet reflections.

Laboratory-grown inclusions look different

Laboratory-grown diamonds are graded on the same clarity scale, but their inclusions reflect how they were grown. HPHT-grown stones can contain metallic flux inclusions, which look dark or reflective. CVD-grown stones can show dark pinpoints of non-diamond carbon and growth-related graining. Many laboratory-grown diamonds are offered at high clarity grades, which makes the usual question sharper: is the grade buying a difference you can see?

Essential language

Eye-clean: A non-standard description meaning inclusions are not visible under stated unaided viewing conditions.
Relief: How strongly a clarity characteristic contrasts with the surrounding diamond.
Feather: A separation within the diamond that may appear white, transparent, or reflective.
Cloud: A group of tiny pinpoint inclusions that can create a hazy appearance.
Metallic flux inclusion: A metal-rich inclusion that can form during HPHT growth; it may look dark or reflective.

Questions to take with you

Is it clean face-up at a normal viewing distance?
Which characteristic set the grade, and where is it?
Do the comments mention clouds or graining not shown?
Does any surface-reaching feature deserve a durability review?
At this size and in this shape, is the stone still clean face-up?