The word diamond comes from the Greek adamas, meaning unconquerable, and, as the most durable natural material on earth, its symbolic meaning is of pure unconquerable love – perfect for engagement. Diamonds are also dazzling and mesmerising to look at. As for buying them, there are a few things you should know. It’s a common misconception that the size (or carat weight) alone determines the quality and value of a natural diamond. However, there are several factors to look out for when choosing a diamond. A great place to start is to consider each of the four C’s: the cut, carat, clarity and colour.

THE 4 C’s

What do they mean?

The four Cs – cut, carat, clarity and colour – determine the value, beauty and rarity of a diamond and are the most important characteristics to consider when buying.


A well-cut diamond will define the way in which it sparkles and interacts with light. The cut isn’t about diamond shape, but its symmetry, proportioning and polish. The cut will determine how carefully the diamond has been crafted. The only cut recognised by GIA is a round brilliant, which makes round brilliants considerably higher in price and the most popular, classic shape.

However, there are several different types of cut that will complement different shapes of diamonds, otherwise known as ‘fancy shapes’ (these shapes include oval, cushion, princess, pear, emerald, marquise, asscher, radiant, and heart-shaped diamonds). A radiant cut can offer more sparkle, a step-cut suits emerald and rectangular shapes, cushion cuts combine square cut with rounded corners, and there are more, each with its own unique quality. We can help you choose the most suitable cut for your personal style, budget and lifestyle.


Carat is the most widely known of the 4 Cs and refers to a diamond’s weight. If you’re new to diamond buying, you’re probably thinking about carats and keen to get as high a carat as possible. Of course, large diamonds tend to weigh more so have a higher carat, but it’s a common misconception to think that carat refers to size. A very high carat diamond will be exceptionally valuable as it’s so rare. Our advice is always to look for a happy balance among the 4Cs rather then get too drawn in by carat weight.

At Alicia J, we will always show you a selection of different carat diamonds once we’ve discussed what you’re looking for and what piece of jewellery you’re thinking of creating with us. Our job is to guide you through all the different aspects of diamonds, including shape and style as well as the 4Cs.


Another of the four key ways we measure diamonds is by their clarity – literally how clear they are. So, if there are any faults – known as blemishes if they’re on the surface, or inclusions if they’re within the stone – these affect the value of the diamond. Having said that, many inclusions and blemishes are almost impossible to spot with the naked eye. They are measured at 10x magnification by a skilled grader to earn their rating.

The most perfect clarity for a diamond is the Flawless rating – but even if you add up the Flawless diamonds with those in the next category down, Internally Flawless, this makes up only half a percent of all the diamonds in the world – they’re extremely rare and very valuable. Our job is to advise you on the best clarity within your budget, while concentrating on a balance of the 4Cs to get the most beautiful and best value diamond for you.


This is often the least well known of the 4Cs – because we tend to assume that diamonds are clear and not coloured. However, these sparkling little gems hold secret tints, including subtle yellows and pinks. The most truly colourless diamonds are known as white diamonds and are the most valuable.

So, one of the grading systems of diamonds is an expert look at its colour. There are also other aspects of a diamond which will influence how we perceive its colour, from the metal its paired with to what diamond shape you choose. We often advise choosing a higher colour grade (our diamonds are graded by the GIA) if you are picking particular shapes including oval or pear, as the clear brilliance shines out with these shapes, and colour impairments can be more visible.

Diamond shapes

Round brilliant is the most popular cut. It’s clear to see why with its beautiful light-reflecting qualities and superior sparkle. The round shape will maximise light and brightness, making a perfect classic engagement ring.


Classic in style, the princess cut can be square or rectangle, with a good range of varying colour and sparkle from each angle. Another popular choice for engagement rings, the princess cut will showcase the quality of your diamond and its clarity.


Emerald cut diamonds give off a more vintage, art deco style and are very popular for their excellent light-reflecting qualities and unique look. Emerald cut diamonds will highlight the colour quality and clarity of your diamond.


This square cut diamond is stylish and unique, similar to the emerald cut, the Asscher cut creates a vintage, antique look and feel. You will find many 1920’s style rings have an Asscher cut.


The stunning marquise is carefully cut, considering both length and width. Because of the long shape of the marquise, it can often create the illusion of a larger diamond a flattering elongation effect for shorter fingers.


Oval cut diamonds are also a popular choice for engagement rings, with many people choosing this as a twist on the classic brilliant-cut. The oval cut offers similar brilliance and fire to the brilliant-cut diamond, with the flattering elongated shaping of the marquise.


The radiant cut can be very striking and unique. It is often popular for radiant cut diamonds to be surrounded with a halo of smaller diamonds, creating a more contemporary style of engagement ring.


Sometimes known as the tear, the pear cut is similar in elegance to the marquise cut. Often designed with a halo of surrounding stones, it creates a wonderfully flattering shape on the hands, making it a popular choice for engagement rings.


Often referred to as the ultimate symbol of romance, heart-shaped diamonds are one of the most popular fancy cuts. This unique cut requires skilled craftsmanship. You may find the shape becomes more defined as the size of the diamond increases.


Also called a pillow cut, these diamonds are square or rectangle with perfectly rounded edges. This style of ring is very traditional, offering a pretty and subtle style.


Sourcing diamonds?

Alicia J diamonds provides a personal diamond sourcing service for our customers. If you are searching for a loose diamond, coloured diamond or gemstone, we can guide you through the process of sourcing the highest quality stone, for the best possible price.

Whether you want to learn more about the basics or need help sourcing the perfect stone for you, our Diamond experts are on hand for honest and professional advice.

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