As they are formed by nature, most diamonds contain imperfections, inclusions or blemishes. Clarity is a measure of these and is an important diamond characteristic. Diamonds with the fewest imperfections are the most desirable and attain the highest clarity grades.

A diamond is only graded as being flawless if no internal or external imperfections are visible when it is magnified ten times. Although the imperfections present in most diamonds are not usually detectable, it is important to understand the system used to grade clarity.

The diamond shows no inclusions or blemishes of any sort under 10x magnification when observed by an experienced diamond grader. Truly flawless and internally flawless diamonds are extremely rare in nature. Internally Flawless (IF) diamonds may have minor surface blemishes.

View a Flawless (IF) diamond with no inclusions

The diamond contains minute inclusions that are difficult even for experienced diamond graders to see under 10x magnification. Again, very rare in nature, VVS diamonds are highly sought after and very valuable. To the naked eye VVS1 and VVS2 diamonds look pristine.

View a diamond with Very Very Small Inclusions (VVS1)
View a diamond with Very Very Small Inclusions (VVS2)

The diamond contains minute inclusions (such as small crystals, clouds or feathers) when observed with effort under 10x magnification. To the naked eye, VS1 and VS2 inclusions are not visible. VS diamonds offer an excellent balance between clarity and cost. This clarity of diamond is widely used by the world's most recognised and respected jewellery brand.

View a diamond with Very Small Inclusions (VS1)
View a diamond with Very Small Inclusions (VS2)

The diamond contains inclusions (for example crystals, knots, pinpoints, clouds & feathers) that are noticeable to an experienced grader under 10x magnification. SI diamond inclusions will typically be invisible to the naked eye and, as such, offer excellent value for money. These 'good commercial grade' diamonds are most commonly set into the more expensive pieces (such as certified engagement rings) sold by the 'higher end' high street retail brands.

View a diamond with Small Inclusions (S1)
View a diamond with Small Inclusions (S2)

The diamond will contain inclusions (possibly large feathers or large included crystals) that are obvious under 10x magnification. These inclusions can often be seen by the naked eye and can affect the transparency, durability and brilliance of the diamond. Used extensively by mass market high-street jewellers and catalogue retailers, Hearts of London do not accept diamonds with a clarity rating of I1 or below.

View a diamond with I1 Inclusions (I1)
View a diamond with I2 Inclusions (I2)
View a diamond with I3 Inclusions (I3)

At Hearts of London, we reject many diamonds that are readily accepted elsewhere in the market and if a diamond's clarity places it on the limit of two gratings, the lowest one is always stated. In addition our qualified gemmologists carefully inspect all of our independently certified diamonds both before and after they are set. This helps to ensure that each diamond is mounted in such a way that it hides any known flaws or blemishes beneath the prongs or the setting.

Our stringent internal procedures and commitment to quality also means that we automatically look for imperfections in any diamond and reject any that have noticeable black inclusions, surface inclusions, drill holes, chips, milky or pervasive clouding, too many facets, internal streaks or surface knots, Furthermore our diamonds are never artificially enhanced.

With the majority of imperfections being so small that they are invisible to the naked eye, it is important not to become too preoccupied with clarity. It is however worth noting that imperfections do increase with the size of the diamond and clients looking for larger diamonds are always advised to opt for a slightly higher clarity rating.

Diamonds with imperfections visible under 10x magnification can provide an affordable solution and imperfections can often be hidden when setting a diamond. Over 99% of gem quality diamonds will contain inclusions. Reputable jewellers should however show you how to inspect a diamond and will point out any imperfections before you purchase. At Hearts of London we do both and using state of the art digital microscopes, we advise clients on how the clarity of a diamond may affect its beauty and value.