A Guide to Diamonds
The Perfect Stone...

Diamonds are incredible. The hardest, sparkliest and most precious of all substances, these special gemstones are formed over billions of years in complete darkness up to 190km below ground! Every diamond has an individual character…and with so many carats, cuts, clarity and colours available, our Diamond Guide will help you decide which stone is the right one for you!


Getting Started: The 4 C's

To differentiate between each unique diamond there is a universally accepted standard used to describe and grade each stone. This is known as the 4 C’s: Cut, Colour, Clarity, and Carat. Using the 4 C’s you can assess the quality of any diamond. Each of the 4 C’s should be considered equally when comparing diamonds but the cut is usually seen as the most defining characteristic.


The Cut

The cut of a diamond is a completely man-made attribute. Diamonds are mined in rough form and then sent to skilled stonecutters to be shaped and polished. Uncut gemstones often look like ordinary stones; it’s the cutting process that transforms these “rocks” into jewels. The cut determines the shape of the diamond. Round is the most popular but shapes include pear, oval, emerald and cushion. The cut also determines how well each of the diamond’s facets interact with light (a standard round cut diamond has at least 58 individual facets!). These precise facets are angled in perfect proportion to one another, creating the ideal cut. The ideal cut maximizes the amount of light that is reflected back from the diamond – creating that all-important sparkle!

Diamonds are the most sought after gems on Earth. Somewhere between one and three billion years old, each gem is totally unique.


The most valuable diamond colour is actually colourless! It is the absence of colour that gives a top quality diamond its crisp whiteness. A colour scale is used to grade each stone. The scale begins with D, which is colourless, and continues with increasing colour to the letter Z. Many of these colour distinctions are so subtle that they are invisible to the untrained eye – but they can make a very big difference to the overall diamond quality and price. As well as being predominantly colourless, diamonds can also be found in a variety of other colours. Coloured diamonds are sometimes called ‘fancies’ and can be highly prized. Colours can include: canary yellow, pink, blue and the smokey champagne hues seen in our Plume Collection! Coloured diamonds are a fantastic alternative to classic white diamonds. They carry all the same qualities of hardness, brilliance and sparkle, with the addition of colour. This can be a great option for anyone looking for a subtle gem where the hue is no less valuable or attractive.


A Little History

Diamonds are the most sought after gems on Earth. Somewhere between one and three billion years old, each gem is totally unique. They are the hardest naturally occurring substance known to man, made of 99.95% pure crystallised carbon which is formed under the Earth’s surface. The qualities of hardness, brilliance and sparkle have become synonymous with diamonds and especially engagement rings. Throughout our history these beautiful and durable gems have come to symbolize love and fidelity.



Natural diamonds are created under the Earth’s surface where carbon is exposed to tremendous heat and pressure. This process can result in a variety of internal characteristics called ‘inclusions’. When evaluating diamond clarity, the number, size and position of any inclusions is taken into account. No diamond is perfectly pure, but the fewer inclusions it has, the closer it comes to perfection and the higher it’s value. Many inclusions are too tiny to be seen by anyone other than a trained diamond grader. To the naked eye, a VS 1 and an S1 2 diamond may look exactly the same. Even though they are different in terms of quality, it’s good not to let your decision be led too much by something you can’t see. As long as you choose a diamond that appeals to you and fits your budget then you should be all right.



The weight (and therefore the size) of a diamond is measured by carat. A carat is equal to 0.2gm. There are several internationally recognized organizations specializing in the assessment and grading of diamonds using the 4 C’s. Independent gemological laboratories such as the GIA, IGI or HRD provide certificates that outline each diamonds unique qualities. It’s important to remember that two diamonds of equal carat weight can have very different values, depending on the other factors in the 4 C’s. When choosing your stone you want a balance between cut, colour, clarity, carat and cost. Spend whatever you like and what you can realistically afford, there’s a diamond out there for every budget!

Choosing Bespoke

If you have a heritage diamond or would prefer to pick your very own unqiue stone, why not consider our Bespke Service. We have been hand-making jewellery in London for over 30 years, so our team is expertly placed to create beautiful one-off pieces, and personally source stones. Discover below how you can take an idea and turn it into your very own piece of Alex Monroe Jewellery.

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