THE 4 C’s

cut . colour . clarity . carat

Cut

& Shape

Cut is the term used to describe the exact dimensions and proportions of a diamond. Cut is the biggest factor affecting the beauty and sparkle of your diamond and is the only factor that is influenced by human hand. A master cutter will shape and cut a rough diamond to maximise its features and inherent value.

The depth, width, angles and proportions are all aspects of a diamond that affect its cut grade. The balance of these will determine how well light passes through the diamond and the diamond is then graded accordingly. There are two types of light emanating from a diamond; brightness and fire. Together they are known as scintillation.

Brightness: The return of white light to the human eye.

Fire: The return of coloured light to the human eye.

Scintillation: The movement of white and coloured light within a diamond to the observer.

There are no definitive measurements that define a diamonds cut, rather the collection of measurements and observations determining the relationship between its light performance, dimensions and finish.

Simply put, we want to see as much light retured to our eye as possible with the facets of the diamond increasing its refractive index (ability to reflect & refract light). A diamond that has been cut to the proportions that return the most light is known as an ideal cut diamond.

Ideal: Maximises Light reflected through the crown.

Too Shallow: Light escapes through the pavillion facets causing the diamond to lose brilliance.

Too Deep: Light is lost out of the pavillion facets causing the diamond to look dark & dull.

The consideration of these factors will determine a diamond’s cut grade which will then affect its value. The higher the cut grade, the more desirable the diamond becomes and so, more valuable. Not all diamond shapes can be given cut grades but those that do are graded on a scale using one of the following grades:

Virtually all of the world’s diamonds sold for use in jewellery are cut to the following twelve shapes. With each shape comes different attributes, numbers of facets and levels of sparkle. The beauty of diamonds is completely subjective and preference on diamond shapes is always led by a person’s tastes. Below is an introduction to each that should help you determine the diamond shape is perfect for you.

Round diamonds are the most popular of the diamond shapes, representing around 75% of all combined diamond sales. The mechanics of this shape lead to the highest levels of light reflection, giving the most sparkle and brightness and their versatile nature means they can be used in most styles and pieces of jewellery. Due to the high demand, low yield and high amount of rough stone lost in the cutting process of round diamonds, they are the most valuable and so most expensive diamond shape available.

Princess cut diamonds are the second most popular shape available, becoming more and more coveted in engagement rings. First created in 1980, the princess cut diamond is traditionally a square cut but is often cut to slightly rectangular proportions with many buyers actually preferring this. Small inclusions to the crown of a princess cut diamond can often be well hidden due to the need to always have four corner claws to secure the diamond. The strong brilliance and straight line facets of a princess cut diamond are very forgiving of inclusions, meaning a buyer can often find a lower clarity grade princess cut diamond to be as visually pleasing as higher grade.

Oval diamonds deliver a similar fire and brilliance to round diamonds whilst giving a unique alternative to the popular favourite. The lengthened look of an oval cut diamond will elongate and give a slender appearance to fingers with the ideal length to width ratio being that of 1.40-1.50. While most oval cut diamonds will present a bow tie effect at their centre (inability to reflect central light out of the diamond due to its style of cut) they do often look larger than other diamond cuts at equal carat weights.

Marquise cut diamonds are American football shaped, helping to elongate fingers and carry the illusion of greater size due to their long appearance. they have one of the longest crown surfaces and their most desirable length to width dimensions are 1.75-2.15. Symmetry is extremely important to Marquise cut diamonds as points and edges that do not align can give the appearance of a poorly set diamond.

Pear shaped diamonds have the visual combination of a round and marquise cut diamond and have increased considerably in popularity over the last ten years. Personal preference plays a big part in the desirability of pear shapes but the most common length to width ratio is between 1.40-1.70. Pear shapes can possess a bow tie in the centre but can hide inclusions well in the pointed end of the diamond and should always be set with a claw at the point.

Cushion cut diamonds is often seen as a mix between round and princess cuts, with four sides and rounded corners. The visual appearance of cushion cuts is a favourite with buyers although they are often cut deeper than other cuts, meaning they appear slightly smaller when compared with other cuts of matching weights.

Emerald cut diamonds are one of the ‘classic’ diamond shapes, with their unique appearance created by step cuts and an open table, delivering a hall-of-mirrors effect as opposed to the sparkle of round diamonds. The less fiery, long lines create flashes of light and accentuate their elegant appeal with a ratio of 1.50 being considered the classic proportions.

Radiant cut diamonds are a strong favourite of ours. Desirable in both square and rectangular shapes their brilliant cut facet pattern at the crown and table create vibrant light movement and are extremely eye catching. Designed for maximum brilliance, they give the sparkle of a round brilliant diamond while offering the popular square edged appearance.

Asscher cut diamonds are similar in shape to radiants but are step cut with a higher crown and smaller table. Their cut corners and square shape give an octagonal appearance while creating the very unique light play found in emerald cut diamonds.

Heart shaped diamonds are a less common cut of diamond but undeniably deliver the symbol of love. Appearances of heart shaped diamonds can differ greatly and symmetry is extremely important, with the desired shape being more prominent in larger sizes. an usual cut of diamond but guaranteed to make an impact in its desired piece of jewellery.

Trillion (or triangular brilliant) diamonds deliver the sharp appearance of a triangle with slightly curved sides. Often used as side / outer diamonds for othe fancy shapes but can quite often be a stunning centrepiece when cut well and set beautifully. When cut at the right proportions they can be very bright and lively diamond and require good symmetry for best appearance.

Baguette diamonds have the same step cut appearance of emerald cut diamonds but maintain their sharp corners. They are mostly used as accent stones, accompanying a centre diamond and found set alongside, within a channel or running down the shoulder of a ring. They are often cut with a taper, meaning the diamond width shrinks as it makes its way to an end.

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