Clarity refers to the presence or absence of certain diamond identifying characteristics, known as inclusions. The location, size, types and color of these inclusions all help to determine where a diamond falls on the clarity grading scale. Clarity is only one characteristic of quality, so don’t use the terms interchangeably. Keep in mind that the higher the clarity, the more rare, and consequently more expensive. Only about 2% of the world’s diamonds are flawless.
The right blending of the four C’s will put a diamond into the right price range for your client. Color and cut (the most obvious after carat weight) influence the price most significantly.
Remember: your client determines which diamond is the “right” quality; our job is to provide objective and accurate information.
Clarity grading terminology
The most widely accepted standard for clarity grading is the scale developed by the Gemological Institute of America (GIA). Its greater number of classifications makes it the strictest system. (An alternative scale is the AGS, which has slightly fewer classifications.)
|IF||No inclusions visible at 10x|
|VVS1||Minute inclusions; extremely difficult to see at 10x|
|VVS2||Minute inclusions; very difficult to see at 10x|
|VS1||Minor inclusions; difficult to see face-up at 10x|
|VS2||Minor inclusions; somewhat easy to see face-up at 10x|
|SI1||Noticeable inclusions; easy to see at 10x|
|SI2||Noticeable inclusions; very easy to see at 10x|
|I1||Obvious inclusions at 10x; visible to the unaided eye|
|I2||Obvious inclusions; easily visible to the unaided eye|
Types of inclusions
Inclusions are internal characteristics that can be colorless, white, black, green, or red.
- Pinpoint: Whitish or dark dot that is very difficult to see.
- Cloud: Cluster of pinpoints; often hazy in appearance and difficult to see
- Darkspot: Silvery, reflective, flat inclusion; like a mirror
- Colorless Crystal: Could consist of a crystal of diamond, a group of crystals, or of a mineral; could lower the diamond from a VS2 to I3.
- Feather: Another name for a crack; not dangerous if it doesn’t break out of facet. Note: thermoshock and ultrashock cleaners can make it bigger.
- Bearding or Girdle Fringes: Happens in the cutting process when the girdle becomesoverheated; develops cracks that look like whiskers. Sometimes can be polished off, sometimes have to facet the girdle. When minimal bearding, can still call a diamond IF
- Growth or Grain Lines: Can only be seen by slowly rotating the stone. Will appear in groups of 2, 3 or 4 pale brown lines if small and not visible through the crown. Won’t have an adverse affect.
- Knaat Twin lines: An included crystal that breaks the surface. External flaws that look like small ridges.
Types of Blemishes (External Flaws)
- Natural: Looks like a rough, unpolished area on the girdle; can look like a scratch or small triangle (trigon). Some don’t call it a flaw if no wider than the normal width of the girdle, or, does not interfere with circumference.
- Nick: Small chip.
- Girdle Roughness: Criss-crossed lines that can be remedied by polishing.
- Pit or Cavities: Holes in the table.
- Scratch: Minor, can be removed by polishing
- Polishing Lines: Won’t lower the value if minor and on the pavilion.
- Abraded or Rough Cutlet: Minor flaw.