Clarity enhancement relates to the process of restoring and
improving the overall appearance of a diamond by removing or
hiding its inclusions. This can be done by filling cracks or fractures
and removing inclusions.
Zvi Yehuda, an Israeli diamond cutter, developed this process in
1982. This process works best for diamonds that have a few small
cracks. It can usually improve the clarity of a diamond by one grade
and should not impact other elements of the stone, such as the
weight or the colour. You can spot a fracture-filled diamond with
ease using a microscope or 10x diamond loupe. By adjusting and
turning the stone from side to side you will notice the colour change
from a purple to a yellowy shade. This has been caused by the
Low cost – The ability to buy a cleaner and larger diamond for less
Higher grading – Clarity grading boosted by one or two grades.
Is this really a cost efficient option? You pay less money and it may
appear that you have more value. But in reality the inclusions are
still there and the diamond has also been weakened. See below.
Post treatment the stone will be weaker and more susceptible to
damage, either from wear or tear, resizing or remounting.
Often it is too risky and complicated to treat a diamond – the stone
may be too small or too heavily marked.
The appearance of the stone may diminish. Some experts believe a
higher grading will not be achieved because the stone’s appearance
could diminish over time.
Clarity Enhanced Diamonds
Advanced technology nowadays has enabled the jewellery industry to
improve the visual appearance of lower grade diamonds by the process of
laser drilling or fracture filling. This practice is referred to as "clarity
enhancement". Laser drilling, and fracture filling treatments result in an
unnatural product. These diamonds have been altered and are no longer
considered "natural" diamonds.
The treatments are permanent as long as the diamonds are never introduced
to a jeweller’s torch (as in sizing or mounting). High heat or any type of acid or
caustic substance will not affect a natural diamond. A treated or an enhanced
diamond will crack or break in these environments.
The cost of treated diamonds should be at least 50% less than a natural
diamond. Some retail jewellers do not disclose the fact that a diamond has
been fracture-filled or laser drilled. Jewellers can simply write the abbreviation
“CE” for “clarity enhanced” on the paperwork. An unsuspecting customer
might never know what that means. For customers who wish to purchase
diamonds as an investment treated diamonds cannot and will not appreciate
in value or hold value as would an untreated diamond.
Laser Drilled Diamonds
Description: Laser drilling creates a minuscule passageway into the heart of a
diamond. This is a small tunnel that is used to reach a large inclusion in a
diamond. The manmade opening allows for further treatments, such as boiling
out included crystals with acid. In other cases, an internal fracture, feather or
knot, can be laser drilled to create a passageway to introduce glass-like
substances that soften or minimize their appearance. Once a laser-drilled hole
is filled, the Federal Trade Commission states the treatment must be
Detection: Laser drilled holes are sometimes noticeable without the aid of a
10X loupe but it is thought that the drilling is less noticeable than a natural
birthmark in a stone, such as black carbon. When looking through the pavilion
of a diamond the facets reflect the drill hole, so it appears that there is more
than one. The purple pools of colour at the bottom of the drill holes are called
a “flash effect” and signal that the area has been treated with a diamond-filling
compound to make it appear clearer.
Fracture Filled Diamonds
Description: This treatment process eliminates most eye-visible fractures and
feathers in a natural diamond. The artificial filler does not add any colouring or
measurable weight to a treated stone. Fracture filled diamonds are hard to
detect with the naked eye because the filler closely matches a diamond’s
refractive index. While treatment can improve a stone’s clarity, it cannot be
used to fill voids and laser drilled holes in a diamond. The treatment is
permanent even under prolonged exposure to sunlight and ultraviolet lighting.
However, the direct heat of a jeweller’s torch and contact with acid can alter
Detection: This treatment is virtually impossible to detect with the naked eye,
but every fracture filled diamond has a built-in signature called the “flash
effect”. All fracture filled diamonds will reflect either a purplish-blue or green
colour when examined under a 10X loupe.
Fracture filled diamonds cost approximately 50% less than comparable non-
Israel Diamond Supply does not carry or sell any treated diamonds,
including laser drilled and fracture filled diamonds. Furthermore, Israel
Diamond Supply advises against the purchase of any treated diamonds.
It is always a better investment to own a smaller, natural, unaltered
diamond rather than a larger treated diamond.