A diamond clarity grade is a measure of how free the diamond is from internal inclusions (imperfections), or external blemishes (marks of various kinds). Diamonds which have no inclusions or blemishes are incredibly rare in nature. Most diamonds have flaws which cannot be seen except using 10x magnification - which is how diamonds are graded. Such flaws do not affect the beauty of the diamond. Diamond Clarity Grades Abbreviation Clarity Grade Description FL Flawless FL diamonds are flawless with no inclusions and no external blemishes. Diamonds in this grade are extremely scarce. IF Internally Flawless Diamonds in this grade have no inclusions and are much sought after because they are so rare. VVS1 Very, Very Slightly Included Inclusions are difficult to see, even when using a microscope. This is one of the top clarity grades available for purchase and offers exceptional brilliance. VVS2 Very, Very Slightly Included Inclusions are difficult to see, even when using a microscope, and are invisible without magnification. This is one of the highest clarity grades available and represents a fine investment. VS1 Very Slightly Included VS1 diamonds have inclusions which are not visible to the naked eye, and only just visible using 10x magnification. These diamonds offer exceptional value for money. VS2 Very Slightly Included VS2 diamonds have inclusions which are only just visible using 10x magnification. The inclusions are not visible to the naked eye. These diamonds offer exceptional value for the price. SI1 Slightly Included SI1 diamonds have tiny inclusions which can be seen using 10x magnification but are almost never visible to the naked eye. SI1 diamonds represent excellent value for those on a more limited budget. SI2 Slightly Included SI2 diamonds have miniscule inclusions which can be seen using 10x magnification. They may occasionally be visible without magnification. This clarity grade is popular with those seeking a balance between first-rate value and a lower budget. SI3 Slightly Included SI3 diamonds have minute inclusions which may be seen using a jeweler's loupe with 10x magnification. These inclusions may sometimes also be visible without magnification. I1-2-3 I1-2-3 Included These diamonds have inclusions which can sometimes be noticed by the naked eye and usually when using 10x magnification.