When you buy a diamond, the 4 C’s - colour, clarity, carat and cut - are the four most important things to think about. It is the way that the 4C’s relate that gives value and beauty to your diamond…



Cut has the biggest impact on the beauty of diamonds. It not only refers to the shape of different diamond cuts but also addresses the proportions, symmetry and polish commonly called the ‘make’ of the stone. The cut determines the diamond’s fire and brilliance. An expertly cut diamond optimises the beauty of the stone which will dazzle in candle light. A poorly cut diamond will need bright lights to stand out and will look dull and lifeless in normal lighting. Imagine having a “D” flawless diamond with no sparkle.



Carat refers to the weight of your diamond. One carat is divided into 100 points. 0.75cts = 75 points. 0.50cts = 50 points. Above, is an enlarged representation of carat weight. Carat weight alone does not determine a diamond’s value. Value is attained by a combination of the 4C’s. Larger diamonds are much more rare and therefore much more valuable.



When looking at diamonds a completely colourless diamond is the finest diamond you can buy. Its lack of imperfections allows it to absorb more light thus reflecting maximum ‘fire’ and ‘brilliance’. ‘D’ colour diamonds are the rarest and the best colour grade of diamond available. We always have a selection of ‘D’ colour in stock. The difference between 2 colour grades can make a significant difference to the price of a diamond. At Prestons we generally offer diamonds graded between the colour of ‘D’ and ‘H’.



All natural diamonds contain identifying characteristics. Clarity is the degree to which a stone is free from external marks called blemishes and internal features called inclusions, or flaws. A diamond does not have to be flawless to be beautiful. We will reject every diamond offered to us with obvious inclusions visible in the ‘table’ facet or surface inclusions on the girdle. At Prestons no diamond will have obvious black inclusions.

At Prestons we aim to be able to compete on quality, design and price with the best there is, anywhere in the world. It takes a lifetime to know your diamonds so we have a team of specialists in store to guide you to your perfect diamond.

“Our showrooms always have a selection of exquisite diamond rings and diamond jewellery available to view in store or alternatively, our in-house jewellery designer can create a completely bespoke piece for you…”

Karl Massey, Managing Director – Prestons

Bespoke Design

Our in-house jewellery designer, Katrina Young, specialises in hand-sketching timeless bespoke pieces, re-working existing jewellery or creating unique pieces for a special occasion. With our international contacts for precious stones and diamonds, Katrina is always available by appointment at Prestons Wilmslow or Prestons Guildford.


Engagement Rings at Prestons

Classic, elegant and timeless, our selection of engagement rings includes a vast variety of exquisite styles all hand chosen to be a part of our exceptional collection.