Diamond Clarity – The 4Cs of Diamonds

GIA Diamond scaleDiamonds are formed deep within the earth  under extreme pressure and heat , they contain unique marks, either internal (inclusions) or external (blemishes).

Diamond clarity refers to the absence of blemishes, marks or inclusions .  Any diamonds without these type of marks are rare, and rarity affects a diamond’s value. Using the GIA International Diamond Grading System™, diamonds are assigned a clarity grade that ranges from flawless (FL) to diamonds with obvious  inclusions (I3).

Every diamond is unique. None is absolutely perfect under 10× magnification, although some do come close. Known as “Flawless diamonds”, these are exceptionally rare. Most jewelers have never even seen one.

The GIA Clarity Scale contains 11 grades, with most diamonds falling into the VS (very slightly included) or SI (slightly included) categories. In determining a clarity grade, the GIA system considers the size, nature, position, color or relief, and quantity of clarity characteristics visible under 10× magnification.

  • Flawless (FL) – No inclusions or blemishes are visible to a skilled grader using 10× magnification. Blemishes only can be on the pavillion.
  • Internally Flawless (IF) – No inclusions and only blemishes are visible to a skilled grader using 10× magnification.
  • Very, Very Slightly Included (VVS1 and VVS2) – Inclusions are difficult for a skilled grader to see under 10× magnification and are considered minute.
  • Very Slightly Included (VS1 and VS2) – Inclusions are visible under
  • 10× magnification but can be characterized as minor.
  • Slightly Included (SI1 and SI2) – Inclusions are noticeable to a skilled grader using 10× magnification
  • Included (I1, I2, and I3) – Inclusions are obvious under 10× magnification and may affect transparency and brilliance

How did the GIA Clarity Scale come about?

Like the color scale, GIA’s clarity grading system developed because jewelers were using terms that were easily misinterpreted, such as “loupe clean,” or “piqué.” Today, when you buy a diamond in another part of the world, the jeweler will most certainly use terms such as VVS1 or SI2, even if her language is French or Japanese instead of English.