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- Diamonds
Diamonds
The Four Cs
They're the hardest substance on earth. They're a girl's best friend. They're forever. In fact, there's an awful lot to say about diamonds. But at Mappin & Webb, we prefer to simply think of diamonds as a declaration - of love, of loyalty, of sheer, spontaneous happiness.
But before you go about choosing that perfect diamond, we think it's important you understand exactly what it is you're buying. So we've put together this guide to assist you as you start looking.
There are four main criteria to bear in mind, when buying your diamond. For convenience' sake, we call them the 'Four Cs'. These are cut, colour, clarity and caratweight (of course there is another C, cost, but we'll leave that for you to decide).
Cut
Diamonds are renowned for their ability to transmit light; the cut of the diamond determines its brilliance, dimensions and finish. A diamond that is cut to good proportions handles the light better, creating more brilliance and sparkle and, therefore, commanding a higher value. Transforming a diamond from its natural, rough state to a glittering, perfect jewel can take weeks, even months.
Measurements of cut quality include: Brightness, the internal and external white light that is reflected from the diamond; Fire, the scattering of the white light into myriad rainbow colours; Scintillation, the amount of sparkle that is produced, or the pattern created through light and dark areas.
Mappin & Webb diamonds are carefully considered and selected for their brilliance and undergo vigorous quality assessments.

Types of Diamond Cuts
Clarity
Clarity is graded based on the number, location, size and type of 'inclusions'. These are nature's birthmarks and are sometimes referred to as 'flaws'. Natural diamonds are the result of carbon exposed to extreme heat and pressure deep in the earth. It is this process which creates the 'inclusions' and 'blemishes' that characterise the diamond and thus contribute to its value.
Most diamonds contain miniscule inclusions that make each and every one unique. These inclusions neither mar the beauty nor endanger the durability of a diamond, although a stone will sparkle more the fewer and smaller the inclusions are.
Carat
Like all precious stones, diamonds are weighed in carats. Originally, they were measured with carob seeds, and this may be where the word 'carat' comes from. Later the system became more scientific, and one carat was standardised at 0.2 grams.
Fewer than 5% of diamonds used in jewellery weigh more than a carat. Most are weighed in hundredths of a carat, or 'points'. So 50 points is a half of a carat, or 0.50 carats.
Colour
The colour of a diamond is the final consideration when reflecting on the Four Cs. When we think of diamonds, we usually think of them as totally colourless. And, while these are the rarest and most valuable, they come in a whole range of other colours, like pink, blue or green. These are also very rare and, needless to say, very valuable.
We use the alphabet to grade colour. 'D' denotes colourless, and we move along the alphabet as any colour gets more visible.

A look at Diamond Clarity, Carats and Colours
© 2023 Mappin & Webb
Mappin & Webb is a trading name of Watches of Switzerland Company Limited. Registered Office: Aurum House, 2 Elland Road, Braunstone, Leicester, LE3 1TT, Registered in England and Wales, Company number 00146087. Registered VAT Number 834 8634 04. Watches of Switzerland Company Limited acts as a broker and not a lender and offers finance from Secured Trust Bank PLC trading as V12 Retail Finance and PayPal (Europe) S.à r.l. et Cie, S.C.A., 22-24 Boulevard Royal L-2449, Luxembourg trading as PayPal Credit. Watches of Switzerland Company Limited is authorised and regulated by the Finance Conduct Authority. Our registration number is 308710. Credit provided is subject to age and status, minimum spend applies. Terms and Conditions apply. UK residents only. We may receive a commission if your application is successful, and the amount may vary depending on the product chosen and the amount of credit taken out. Not all products are regulated by the Financial Conduct Authority and FOS protection will not be extended to unregulated agreements. Please note the Consumer Credit Act states that should your purchase / loan amount cost more than £30,000 you will not be covered under Section 75 of the Consumer Credit Act.
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