September 23, 2020

Diamond clarity refers to the absence of inclusions and blemishes inside a diamond. It is one of the 4Cs used to determine diamond quality and value. This complete guide covers everything you need to know about diamond clarity grading scales, what inclusions are, and how clarity affects appearance and price.

What is Diamond Clarity?

Diamond clarity is an evaluation of the number, size, relief, nature, and position of internal characteristics called inclusions and external characteristics known as blemishes.

Inclusions are tiny natural irregularities that occur when a diamond forms underground. Diamonds with fewer and smaller inclusions are considered higher clarity. Blemishes are surface flaws that occur during the cutting and polishing process.

Evaluating diamond clarity involves carefully analyzing these characteristics under magnification to determine how they affect the overall beauty and eye-clean appearance of the diamond.

GIA Diamond Clarity Scale

The Gemological Institute of America (GIA) diamond clarity grading scale is the universally accepted standard for assessing diamond clarity. The GIA clarity scale contains 11 specific grades, from Flawless to Included, based on the visibility of inclusions under 10x magnification:

  • Flawless (FL) - No inclusions or blemishes. Extremely rare.
  • Internally Flawless (IF) - No inclusions, only minor blemishes. Very rare.
  • Very Very Slightly Included (VVS1, VVS2) - Inclusions difficult for experts to see under 10x magnification.
  • Very Slightly Included (VS1, VS2) - Minor inclusions observed by experts under 10x magnification.
  • Slightly Included (SI1, SI2) - Noticeable inclusions under 10x magnification.
  • Included (I1, I2, I3) - Obvious inclusions visible under 10x magnification that may impact appearance.

Diamonds graded as SI2 and higher are considered eye-clean, meaning inclusions are invisible to the unaided eye. With an I1 clarity grade, inclusions may start to be visible without magnification.

GIA's clarity grading analysis is extremely stringent to maintain consistency across millions of diamonds. Other labs may use broader clarity grades.

Evaluating Diamond Clarity

Diamond clarity grading involves a comprehensive analysis of inclusions and blemishes:

  • Size - The dimensions of identifiable characteristics are measured in millimeters. Larger inclusions have greater impact on clarity grade.
  • Number - How many identifiable characteristics are present. Typically fewer inclusions means higher clarity grade.
  • Position - Location of inclusions relative to table and crown. Inclusions under the table have less effect on appearance.
  • Relief - How an inclusion sits within the diamond. High relief inclusions are more visible through the crown.
  • Nature - Type of inclusion. Crystalline inclusions are more appealing than dark clouds or cracks.
  • Blemishes - Quantity, size and position of external surface flaws caused by the cutting/polishing process.

This thorough examination under 10x magnification determines how various clarity characteristics affect the diamond's brilliance, dispersion of light, and apparent eye-cleanliness.

Eye-Clean Diamonds

"Eye-clean" means no inclusions or blemishes are visible to the unaided eye. Eye-clean diamonds include clarity grades:

  • Flawless (FL)
  • Internally Flawless (IF)
  • Very Very Slightly Included (VVS1 - VVS2)
  • Very Slightly Included (VS1 - VS2)

Diamonds graded SI1 and below may start to exhibit minor inclusions visible without magnification. However, inclusions that are faint, white, transparent, or situated under the bezel can still result in an eye-clean SI1 or SI2 diamond.

Depending on the number, size, nature, relief and position of inclusions in the stone, even some I1 diamonds can face up eye-clean. However, diamonds graded I1 have obvious inclusions that potentially impact transparency and brilliance.

How Clarity Affects Diamond Value


Higher diamond clarity comes with exponentially greater rarity in nature and higher prices per carat as a result. As clarity grade declines, diamonds become far more plentiful and costs decrease steadily.

For example, a 1 carat round diamond may sell for (on average):

  • FL - $11,000
  • IF - $10,200
  • VVS1 - $9,500
  • VS1 - $8,000
  • SI1 - $5,500
  • I1 - $3,200

The difference in price between IF and I1 can be over 300% for diamonds of the same shape, cut, color and carat weight.

Clarity is one of the 4Cs that directly impacts the perceived beauty and value of a diamond. While a lower clarity grade can represent a smart purchase in some instances, diamonds with higher clarity grades will have greater brilliance and appeal.

How to Choose Clarity for Engagement Rings & Jewelry

  • For rings, prioritize eye-clean diamonds (VS2 and above).
  • Evaluate inclusions under magnification for visibility.
  • Consider fluorescence if eye-clean appearance is borderline.
  • Buy clarity just below major grade thresholds to save (eg. VS2 over VVS2).
  • Choose lower clarities for smaller diamonds under 0.50 carats.
  • Excellent cut can help mask some inclusions.
  • Discuss your budget and preferences with a jeweler.

With some education on diamond clarity characteristics, it is possible to find beautiful eye-clean diamonds across many clarity grades at accessible price points for every customer.

Takeaway Tips

  • Clarity assesses internal and external characteristics.
  • GIA scale ranges from Flawless to Included based on inclusion visibility.
  • Eye-clean diamonds have no visible inclusions without magnification.
  • Higher clarities are exponentially rarer and more expensive.
  • Cut quality influences how inclusions impact appearance.
  • Select clarity grade based on visibility, budget and diamond size.

Understanding GIA's diamond clarity grading system is key to making an informed decision with confidence. Be sure to review the diamond under magnification yourself to evaluate the inclusions and ensure an eye-clean appearance.

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