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The Guide to
choosing your

Diamonds are not only the hardest natural substance known
to man, they’re also the most highly valued of gemstones.

Diamonds come in many shapes, sizes, colours and prices so
we have created this guide to help simplify it all.

To understand the visual appeal of diamonds there are four
factors to consider. Carat, Colour, Clarity and Cut.


Simply put, Carat is another way of explaining weight.
Diamonds are weighted in metric carats:


The colour of Diamond is due to the presence of nitrogen, boron
and hydrogen, which causes irregularities in the crystal.
Naturally coloured Diamonds can be very valuable.

Today, colour grading has been defined by the GIA, and they’re set
apart by letters of the alphabet (starting with the letter D).

At Cred, our standard range will always be better than “i”,
we don’t order below this unless specifically requested.


Clarity describes how free the stone is from inclusions and blemishes
under magnification of x10. Almost all diamonds contain minute traces of
non-crystalised carbon or small non-diamond crystals, however, their position
is important and will affect the final prices of the diamond.

Definitions of clarity grades according to internal defects:

Loupe clean. A diamond is termed loupe clean when an expert finds no internal defects with a x10 loupe

Very, very small internal defects which can be detected by an expert with a
x10 loupe only with degrees of difficulty ranging from very considerable to great. Size, position and number determine the distinction
between 1 and 2

Very small internal defects which can be detected by the expert with degrees of difficulty ranging from not too difficult to easy.

SI1 SI2 – Small internal defects which are easy for the expert to detected with a x10 loupe.

Internal defects which are very
difficult for the expert to detect with the naked eye

Large and /or numerous internal defects which are easily detectable by the expert with the naked eye and which slightly diminishes brilliance

Large and /or numerous internal defects
which are very easily detectable by an
expert with a naked eye and which
diminishes brilliance.


The cut of a diamond, its proportions and symmetry
are really important to its value.

The most popular diamond shape is the round brilliant-cut
which is based on specific calculations aiming at maximising
beauty. Other shapes, such as the emerald-cut, oval, pear, heart,
princess-cut, and marquise, are referred to as a “fancy cut”.
The ideally cut diamond will have light rays from all sides that
are bent towards the centre of the stone and then reflected
back through the top.

The added value you get from a CRED diamond or
semi-precious stone is that all our stones are guaranteed
to come from legitimate sources and not funding civil
wars and internal conflicts.

Read more about our diamonds and gems here

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