| FL |
 |
Flawless |
FL (flawless) - no inclusions or blemishes of any sort are visible to a skilled diamond grader using 10x magnification. |
| IF |
 |
Internally Flawless |
IF (internally flawless) - no inclusions and only blemishes are visible to a skilled diamond grader using 10x magnification. |
| VVS |
 |
Very Very Slightly Included |
VVS1 and VVS2 (very very slightly included) - inclusions are difficult for a skilled diamond grader to see using 10x magnification. |
| VS |
 |
Very Slightly Included |
VS1 and VS2 (very slightly included) - inclusions are minor and range from difficult to somewhat easy for a skilled diamond grader to see under 10x magnification. |
| SI |
 |
Slightly Included |
SI1 and SI2 (slightly included) - inclusions are noticeable to a skilled diamond grader using 10x magnification. |
