Choosing Your Diamond

The Four 'C's

Understanding the 4 C’s of Diamonds

One of the first things most people learn about diamonds is that not all diamonds are created equal!  In fact, every diamond is unique.  Diamonds come in many sizes, shapes, colours, and with various internal characteristics.
All polished diamonds are valuable.  That value is based on a combination of factors. Rarity is one of those factors.  Diamonds with certain qualities are more rare – and therefore more valuable – than diamonds which lack them.
Jewellery professionals use a systematic way to evaluate and discuss these factors otherwise there would be no way to compare one diamond to another or evaluate and discuss the qualities of an individual diamond. They use the grading system developed by the Gemological Institute of America (known as GIA) in the 1950s, which established the use of four important factors to describe and classify diamonds: Colour, Clarity, Cut and Carat Weight.


As previously stated, diamonds contain crystals or minerals, formed during their creation in the earth and visible to the trained eye as minuscule specks.  It is these tiny blemishes, known as inclusions, which affect a diamond’s clarity and make it possible to compare two diamonds of exactly the same cut, carat and colour.  Ranked on a scale of clarity, the most perfect “flawless” diamonds are renowned for their rarity and value.

There are 11 clarity grades in the GIA clarity grading system.  They are Flawless, Internally Flawless, two categories of Very, Very Slightly Included, two categories of Slightly Included, and three categories of Included.


A diamond is a true wonder of nature, but it is only when a master cutter gets to work that its true brilliance is revealed.  Diamond cutting requires great artistry and accuracy, and we only buy our diamonds from a small number of suppliers who excel at both.

The cut of a stone also refers to its shape.  The round brilliant cut is the most popular. Its multi-faceted, symmetrical design gives an exceptional sparkle, working particularly well for engagement rings.  But there are many others to consider.  Here at Anja Potze Fine Jewellery, we use most of them – Round Brilliant, Princess, Emerald, Oval, Marquise, Pear, Asscher, Radiant, Heart, Cushion, Baguette and Trillion.


Using colour to describe a diamond is something of an anomaly. Graded on the GIA scale of D to Z, the finest-quality white diamonds are D which are colourless like a drop of pure water.

It is this absence of colour that intensifies the flashes of fire visible in the very best diamonds. D and E colour diamonds are frequently referred to as “exceptional whites”, F and G’s as “rare whites”, and only an experienced gemmologist can distinguish between them.

Carat (Size)

Carat weight is the factor that people might first think is the most important.  How big is it?  But it’s just not that simple because carat is a measure of weight, not size, and the cut of a diamond can make it appear larger or smaller than it actually is.  Also, it doesn’t follow that a two carat diamond will be twice as expensive as a one carat diamond of identical colour, clarity and cut.  Larger diamonds occur less frequently in nature, making them rarer and therefore much more valuable.

Choose your perfect diamond

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