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 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)
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.