FL (Flawless) to I3 (Included). Every inclusion mapped with precision under 10x magnification.
Diamond clarity measures the presence of internal characteristics (inclusions) and surface irregularities (blemishes). These natural features are formed during the diamond's creation deep within the earth and serve as unique identifying markers, much like a fingerprint.
BGI's clarity grading within the 6C system follows rigorous standards. Each diamond is examined under 10x magnification using a gemological microscope, and every inclusion is documented for type, size, position, and color. This detailed mapping ensures precision and provides a permanent record for verification.
BGI gemologists systematically examine each diamond using dark-field and bright-field illumination techniques. Inclusions are categorized by type (crystal, feather, cloud, needle, etc.), plotted on a diagram, and assessed for their impact on overall appearance.
The clarity grade is determined by evaluating five key factors: size of inclusions, number of inclusions, position (location within the diamond), nature (type of inclusion), and relief (contrast against the diamond). This comprehensive approach ensures consistent, accurate grading.
Higher clarity grades command premium prices due to rarity. FL and IF diamonds are exceptionally rare, especially in larger carat weights. VS and SI grades offer excellent value as their inclusions are typically invisible to the naked eye, making them popular choices for engagement rings and fine jewelry.
| Grade | Name | Description |
|---|---|---|
| FL | Flawless | No inclusions or blemishes visible under 10x. |
| IF | Internally Flawless | No inclusions; minor surface blemishes only. |
| VVS1 – VVS2 | Very Very Slightly Included | Extremely difficult to see under 10x. |
| VS1 – VS2 | Very Slightly Included | Minor inclusions difficult to see under 10x. |
| SI1 – SI2 | Slightly Included | Inclusions easy to see under 10x; may be invisible to naked eye. |
| I1 – I2 – I3 | Included | Inclusions visible to the naked eye. |
Last Updated: June 2026 · BGI 6C Diamond Standards™