The grading of a gemstone is based on the presence or absence of inclusions. The fewer inclusions, the better a gemstone’s clarity grade. In diamond grading clarity is one of the four C’s (cut, color, clarity, carat weight) and is divided into defined grading terms which can be found in the table below. Colored stones don’t have such a defined grading system but you will find gemstone dealers using similar descriptions for colored stones.
Clarity
| Main Grade | Subgrade | Name | Short Grade Explanation |
|---|---|---|---|
| Loupe Clean | FL | Flawless | Internally and externally flawless when examined with a loupe. |
| IF | Internally Flawless | Internally flawless. | |
| VVS | VVS1 | Very very slightly included (high end-close to IF) | Very, very small inclusions may be visible when examined with a loupe but the inclusions are not on the table. |
| VVS2 | Very very slightly included (low end-close to VS 1) | Very, very small inclusions may be visible when examined with a loupe. The distinction between VVS 1 and VVS 2 is only made for stones above 0.5 ct. |
|
| VS | VS1 | Very slightly included (high end-close to VVS 2) | Very small inclusions are present that are hard to see with the loupe but the inclusions are not on the table. |
| VS2 | Very slightly included (low end-close to SI 1) | Very small inclusions are present that are hard to see with the loupe. | |
| SI | SI1 | Slightly included (high end-close to VS 2) | Small inclusions are easily observed with the loupe but the inclusions are not on the table. |
| SI2 | Slightly included (low end-close to I 1) | Small inclusions are easily observed with the loupe. | |
| I | I1 | Imperfect 1 | Inclusions are hard to observe with the naked eye, but easily with the loupe. |
| I2 | Imperfect 2 | Inclusions are hard to observe with the naked eye but occur in multiple sites. | |
| I3 | Imperfect 3 | Inclusions are very easily observable with the naked eye and interfere with the brilliance of the stone. |