Diamonds by Forum Jewellers

When choosing a diamond, understanding the 4Cs – Cut, Colour, Clarity and Carat Weight – can help you find the perfect stone. Together, these four characteristics determine a diamond's beauty, rarity and value.

Of all the 4Cs, diamond cut is the factor most influenced by human skill. While a diamond's colour, clarity and carat weight are determined by nature, the quality of the cut depends on the expertise of the diamond cutter.

A well-cut diamond reflects and refracts light from one facet to another, creating the sparkle, brilliance and fire that make diamonds so captivating. When a diamond is cut to the correct proportions, light is returned through the top of the stone, maximising its beauty.

If a diamond is cut too deep or too shallow, light can escape through the sides or bottom of the stone, reducing its brilliance. This is why diamond cut is often considered the most important of the 4Cs when assessing a diamond's overall appearance.

Although many people think of diamonds as colourless, they can occur in a range of natural shades. The most highly prized white diamonds typically display little or no colour, while others may exhibit subtle yellow, brown or grey tones.

Nature also produces exceptionally rare fancy-coloured diamonds, including stunning shades of blue, pink, green, yellow and orange. These unique diamonds are highly sought after for their rarity and beauty.

Almost every natural diamond contains tiny internal characteristics known as inclusions, formed deep within the Earth over millions of years. These natural features are often referred to as nature's fingerprints, making every diamond unique.

Diamond clarity measures the number, size and visibility of these inclusions when viewed under 10x magnification. In most cases, inclusions are invisible to the naked eye and do not affect the beauty of the diamond.

Generally, the fewer inclusions a diamond contains, the rarer and more valuable it becomes.

Diamond carat weight refers to the weight of a diamond rather than its physical size. One carat is equal to 0.2 grams, or one-fifth of a gram.

The term "carat" is believed to originate from the seeds of the carob tree, which were once used as a consistent unit of weight for precious gemstones.

A carat is divided into 100 points. For example:

• 0.25 carat = 25 points
• 0.50 carat = 50 points
• 0.75 carat = 75 points
• 1.00 carat = 100 points

While larger diamonds are generally rarer and more valuable, carat weight should always be considered alongside cut, colour and clarity to find the perfect balance of beauty and value.

Whether you're selecting a diamond engagement ring, diamond earrings or a special gift, the experienced team at Forum Jewellers is always happy to help you understand the 4Cs and find a diamond you'll treasure for a lifetime.

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