Choosing the perfect diamond is an exciting decision, whether it's for an engagement ring, a keepsake to celebrate a special occasion, or simply a timeless piece to add to your jewellery collection.

To help you make the right choice, we’ve broken down the four key factors that determine a diamond's grade and ultimately, value. These are: cut, clarity, colour, and carat - or, the 4 Cs of diamonds. Let’s explore what each of these mean and why they matter.

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Cut refers to how well a diamond has been shaped and faceted, which directly influences a stone's brilliance and sparkle. 

A well-cut diamond will have a better ability to reflect light beautifully and create the signature sparkle this gemstone is renowned for.

Diamond cut is often confused with diamond shape, however the two describe different aspects of a diamond. A diamond cut considers the quality of a diamond’s faceting, while diamond shape describes its geometric appearance, such as ‘pear’.

Why cut matters: A poorly cut diamond, regardless of its clarity, colour, or carat weight, will appear dull and lacklustre, or even misshapen.

Our tip: You can shop with confidence at Molten Store knowing that our gemstone sourcers will only ever select excellently cut diamonds to set in our jewellery, or your bespoke creation.

Clarity measures the purity and rarity of a diamond by assessing the presence of internal inclusions and external blemishes. The fewer the inclusions and blemishes, the higher the clarity grade. 

The GIA diamond clarity scale is composed of six categories, ranging from Flawless (F) to Included (I). These categories are further divided into a total of 11 clarity grades to give a more precise indication of a diamond’s clarity.

Why clarity matters: High clarity ensures that nothing obstructs the passage of light through the diamond, contributing to its overall beauty. 

Our tip: Many inclusions are microscopic and do not affect how a diamond looks to the naked eye, allowing you to find a balance that fits your budget.

Diamonds naturally occur in a range of hues, but the most popular diamonds are typically those that are absent of colour.

The diamond colour grade scale ranges from D (colourless) to Z (light yellow or brown). While traditional white diamonds rank high on this scale, they may still exhibit subtle tints of colour that are generally imperceptible to the untrained eye.

Diamonds, whether natural earth-mined or cultured in a lab, can also be found in hues that exist beyond this scale, such as pink, champagne, and fancy yellow. While not the traditional choice, these bolder hues are often prized for their unique beauty and rarity.

Why colour matters: The less colour in a diamond, the more light it can reflect to enhance its brilliance.

Our tip: Consider the colour grade of your diamond with an open mind. Although the variances between grades may be subtle, they can significantly impact the cost of your diamond.

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Carat refers to the weight of a diamond, with one carat equalling 200 milligrams.

Carat is often confused for a diamond’s visual size, however the two don’t always correlate since the shape, cut and depth of the diamond will affect how its weight is distributed.

To help visualise this, think of a balloon filled with water. It might be perfectly round, or squished long and flat, but the volume remains the same regardless of its shape.

Why carat matters: A diamond’s cut, shape, and overall proportions can make it appear larger or smaller than its carat weight suggests.

Our tip: Our team works with you to find perfect balance between a diamond's size, aesthetic appeal, and cost, ensuring you choose a diamond that meets both your personal and financial preferences.

Understanding the 4 Cs can help you prioritise what’s most important to you in a diamond. Whether it's the dazzling sparkle of a perfect cut, the pristine look of high clarity, the flawless hue of a colourless gem, or the impressive size of a higher carat weight, each characteristic plays a unique role in creating your ideal diamond.

If you’re unsure of where to begin, our expert bespoke team awaits to help you strike the perfect balance between your diamond budget, aesthetic preferences, and values to ensure your dream diamond finery can be brought to life.