Diamond Clarity and Its Effect on Beauty and What A Diamond is Worth

Whether you call them imperfections, characteristics, inclusions, blemishes or flaws, clarity issues make all the difference between a highly valuable diamond and a less valuable diamond. Clarity technically refers to the absence of flaws or imperfections in the stone. The more perfect the stone, the more rare and the more valuable and expensive it will be.

To my mind, talking about a diamond’s clarity characteristics is a polite way of mentioning what we would call its imperfections or “flaws” in normal English. If it is badly flawed, it is naturally going to be worth less.

Diamonds are judged and literally graded based on the relative lack of imperfection. The fewer the flaws, the more perfect the diamond is, the closer to flawless, then the more rare and valuable it is. Very few gem quality diamonds rate an official grade of Flawless or Internally Flawless. These truly near-perfect stones are exceedingly rare – and to find one that close to perfect in a larger size is so jaw droppingly rare, it’s a good bet you will never see one in this lifetime!

The industry standard is to examine the stone under 10x magnification, using a hand loupe, eye loupe, or binocular microscope to locate and identify any unusual clarity characteristics including inclusions and blemishes. These internal and external characteristics are then marked and labeled or noted on a diagram called a plot.

The plot for each diamond is unique, just as each stone is unique. You can use the plot to identify a specific diamond similar to the way a fingerprint can be used to identify an individual person.

Imperfection: Diamond Clarity Characteristics, Inclusions and Blemishes

A diamond can be totally beautiful even if it is flawed. Most diamonds, even gem quality diamonds, have at least a few internal imperfections or “clarity characteristics” (inclusions) and may also have some surface blemishes as well. There are many different kinds of inclusions and blemishes. The most serious internal irregularity or inclusion will “set the grade” for the stone. A stone’s inclusions and blemishes also help identify it, similar to the way a fingerprint identifies a person.

Natural and Man Made Imperfection or Flaws in a Diamond

When diamonds form in nature under great heat and pressure conditions, they are created as gorgeous stones but they are also naturally subject to imperfections. Nearly every gem quality diamond contains naturally formed inclusions such as small internal crystals. Sometimes, too, the diamond can be slightly damaged during the cutting process resulting in small cracks or “feathers”. And diamonds that have undergone laser treatment contain drill holes. These kinds of natural and man-made inclusions are located in a unique pattern inside each stone.

The Plot Diagram or How to Identify Your Diamond

During the grading process, inclusions and blemishes are marked on a custom-drawn diagram somewhat like a map; the diagram is called a plot. There may also be special notations about the diamond’s condition. The plot can then be used forever after to identify that specific stone.

Gem Quality vs. Flaws You Can See

In general, if you can notice an imperfection in a diamond without using a loupe, then it is not gem quality. A gem quality diamond would not have any inclusions – natural or caused by man -- that are visible to the naked eye.

The Loupe or 10 X Magnification

The industry standard is to examine the stone with a loupe that magnifies by the power of ten, also called a 10X loupe. Any inclusions seen at that level of magnification will affect the grade. This is why a diamond can appear perfect -- and yet it may contain flaws.

You might come across a diamond with a surface blemish such as an extra facet or polish lines. Oddly, blemishes do not affect the clarity grade except in the case of Flawless or Internally Flawless stones.

The GIA Clarity Grades Best to Worst

The internationally recognized Gemological Institute of America or GIA Clarity Grades, from best to worst:

• Flawless

• Internally Flawless

• Very Very Slightly Included (VVSI 1 and VVSI 2)

• Very Slightly Included (VSI 1 and VSI 2)

• Slightly Included (SI 1 and SI 2)

• Included (I 1, 2 & 3)

The Significance of Clarity

Of the four C’s or value factors that can be applied to diamond value (otherwise known as the 4 C’s of cut, color, carat weight and clarity), clarity is important in several ways. It can affect how light moves through the diamond, and it can potentially affect the structural integrity of the diamond. Clarity, with its distinctive pattern of inclusions and blemishes, also helps identify each diamond – no two are ever alike! Each diamond is as uniquely an individual as the special person who wears it.

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