Selecting the perfect diamond for your engagement ring

Choosing a diamond engagement ring is a monumental step – it represents a permanent symbol of what will hopefully be the most important relationship of your life and has the potential to cost a small fortune. Get it wrong, and it won’t be forgotten in a hurry!

To help you through this equally thrilling and terrifying process, we take a look at the universally agreed rules on buying diamonds and also the other things you should really consider before taking the plunge.

The 4Cs to choosing a diamond

Even if you’ve never bought a diamond before, you will probably have heard of the 4Cs – Cut, Carat, Colour and Clarity.

Diamond Cut

First things first, this doesn’t refer to the shape of the diamond, but rather how much it sparkles. It’s why it’s often considered the most important of the 4Cs, as even a diamond of high quality will appear dull and lifeless if not cut properly.

A well-cut diamond allows the light to be reflected around the facets and back to the viewer making it look bigger, improving its colour and masking any imperfections. Mostly importantly, it will give your engagement ring that all-important sparkling ‘wow’ factor.

Diamond Carat

Show anyone your new diamond engagement ring and the first question will probably be ‘how many carats is it?’. Carat refers to the weight of the diamond and is equivalent to 0.20 grams. The larger the carat, the pricier the diamond, although the other Cs will have a bearing on cost. If you want to make a memorable impression, then bigger is undoubtedly better, although always take into account your own style and size of hands. You don’t want to buy something you’re not comfortable wearing on a daily basis.

Diamond Colour

Diamonds come in a variety of colours including pinks, blues and yellow, but the majority of engagement rings are set with white diamonds. For these, the clearer and more colourless the diamond, the higher the quality.  A diamond with a yellow tint will prevent light passing through so will lack that all important sparkle.

Diamond Clarity

Most diamonds have what is known as inclusions – small imperfections that are visible inside or on the surface of the diamond itself. The purer and clearer the diamond the more valuable it will be.

Diamond clarity has a grading scale, which takes into account the number, size, colour, reflectivity and position of every flaw visible under 10x magnification. The GIA diamond clarity chart starts at flawless (FL) and runs down to l1 where inclusions are almost always visible to the naked eye.

 If you really want a large diamond engagement ring, but want to keep the cost down, consider a diamond with some inclusions which aren’t visible to the naked eye.

Beyond the 4Cs

If you really want to get the perfect diamond engagement ring, here are a few other things you should think about.

Diamond engagement ring Budget

It should come as no surprise that the old adage that you should spend one month’s salary on an engagement ring came from a De Beers advertising campaign back in the 1930s!

Our advice is take a serious look at your own finances and then decide what you can and what you want to spend on an engagement ring. The good news is, no matter how large or small your budget, you can get a great diamond engagement ring. Simply by choosing a bigger stone of less quality or sacrificing colour for a better cut, you can still have something that is truly special without breaking the bank.


Round, princess, oval, heart –  there are a number of different shapes you can choose from.  Round brilliant cut diamonds tend to be most popular choice, as they sparkle the most, but because they are harder to cut, they also tend to be more expensive.

Try on different shapes and see how they look and feel. You might have your heart set on a round diamond but be surprised by how good a marquise cut diamond ring looks on your finger.


In your excitement at choosing a diamond engagement ring, don’t forget to give some thought to how it’s going to fit with your wedding band. There is nothing worse than finding the two won’t work together.

We can advise you on design and if you heart is set on a particular engagement ring; talk to us about our bespoke jewellery commissions, as we will be able to design a wedding band that will fit perfectly.


Often known as the 5C, diamond certification is proof that the diamond has undergone an unbiased and professional examination and gives you peace-of-mind that you are getting what you are paying for.

The only perfect diamond is the diamond that is perfect for you in terms of shape, design and budget. We stock a wide range of diamond engagement rings and can also source any piece you want to try with no obligation to buy.

And if you are after something truly special, come and have a chat to us about our bespoke jewellery commissions.

We stock a fabulous range of jewellery, so if you are looking to buy diamonds, please visit us in our store in Amersham Old Town, Buckinghamshire. And if you are after something truly special, come and have a chat to us about our bespoke jewellery commissions.