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Diamond Clarity

Diamond clarity is the assessment of small imperfections on the surface and internally. The surface flaws are called blemishes, and internal defects are known as inclusions. These tiny, natural blemishes and inclusions are microscopic and do not affect a diamond’s beauty in any way. Diamonds with the least and smallest inclusions receive the highest clarity grades.

Clarity is one of the 4Cs of diamond grading and quality. Diamond clarity is the least important factor when choosing to buy a diamond because most diamonds have blemishes and small inclusions that are microscopic, unable to be seen with an untrained or unaided eye.

Diamond Types According to the GIA Clarity Grading Scale

In 1953, Richard T. Liddicoat and colleagues established the Gemmological Institute of America (GIA) diamond grading system and clarity scale. The GIA diamond grading scale is divided into six categories and eleven diamond clarity grades. On the diamond clarity scale, also commonly referred to as the diamond grading chart, the complete list of diamond grading categories and clarity grades are listed below:

FL diamond example

Flawless (FL) Diamonds

Inclusions and blemishes aren’t visible on flawless diamonds, even under 10x magnification. Less than 1% of all diamonds are FL clarity. A flawless diamond is incredibly rare because it's nearly impossible to find a diamond 100% free of inclusions. Six percent of customers buy FL diamonds.

Shop FL Diamonds

Diamond Clarity Buying Tips

In the market for an engagement ring or fine diamond jewellery? Here are a few things you should know about what diamond clarity means when it comes to diamond quality and how different clarity grades affect price.

All Diamonds Are Imperfect

Because they’re made underground, most diamonds have small inclusions and blemishes. When referring to inclusions, diamond experts often use the term “internal characteristics” instead. Internal characteristics of natural diamonds are what gives the diamond its character and uniqueness.

Inclusion Examples

  • Clouds
  • Feathers
  • Crystals or minerals
  • Knots
  • Cavities
  • Cleavage
  • Internal graining

Blemish Examples

  • Polish lines
  • Scratches
  • Nicks
  • Pits
  • Chips
  • Breaks
  • Dark or light spots

VS Diamonds and SI Diamonds are the Best Value

For the best value, select a diamond with inclusions that can’t be seen through the crown without magnification (also known as eye-clean diamonds), such as an SI or VS clarity grade. These diamonds are much less expensive than the extremely rare Flawless (FL) or Internally Flawless (IF) diamonds.

Diamond Shape & Size Affect Clarity

Diamond shape and cut play with and impact diamond clarity in different ways.

Diamond Shape — Some diamond shapes require a higher clarity grade than others. Emerald and Asscher-shaped diamonds (referred to as step cut) are designed with rectangular facets that emphasise transparency and let you see farther down into the diamond, which can make inclusions more visible. For these diamond shapes, choose a clarity grade of VS1 or better to ensure the inclusions will not be visible.

Conversely, round, princess, oval, marquise, pear, and heart-shaped diamonds may not require as high of a clarity grade. Cut with a brilliant facet pattern, which reflects light from many different angles, these shapes naturally hide many inclusions.

Diamond Size — As diamond size increases, the size of the facets (the multiple mirror-like surfaces on the diamond) also increases. This can make inclusions more visible. Be sure to prioritize a higher clarity grade as the size of your diamond increases.

There Are 5 Diamond Grading Factors for Clarity

When diamonds are graded, they are magnified 10x. The clarity grade of a diamond is based on the most noticeable inclusions when magnified by 10x. Any inclusions or characteristics that don’t get factored into the grade may still be noted on what’s called a diamond plot chart.

The five diamond clarity factors are:

  • Size — First to get looked at is the size of a characteristic or inclusion. The larger or more noticeable a characteristic, the lower the likely clarity grade.
  • Number — Next is number of easily seen characteristics, not number of total characteristics. Having fewer characteristics means a higher clarity grade.
  • Position — The third factor is the position of a given characteristic; is it under the table (most visible) and close to a pavilion? This position turns inclusions into reflectors, which have a bigger impact on the clarity grade.
  • Nature — Then there is the nature of a diamond characteristic, or whether it’s internal or external. Internal characteristics cannot be graded as flawless or internally flawless diamonds.
  • Colour and relief — Colour and relief is essentially a measure of how easily seen a characteristic is, or how much contrast there is between the characteristic and surrounding diamond.

Shop Blue Nile Diamonds By Clarity Grade

At Blue Nile, we offer the highest quality diamonds and deliver the best value for your budget. If you're shopping for a diamond ring or other diamond jewellery, we offer the following diamond clarity grades:

Flawless Diamonds

Slightly Included Diamonds

Next: Diamond Carat Weight