The most popular shape for a diamond is the round brilliant cut diamond, which reflects the maximum light and sparkles more than any other shape. Diamond cutters use advanced theories of light behaviour and precise mathematical calculations to optimise the fire and brilliance in a round diamond.

A classic  shape that accounts for more than half of all diamonds sold. They are slightly more expensive than other shape because 50% of the rough diamond is lost when cutting a round shape.

Princess cuts are square or rectangular brilliant cuts that display exceptional brilliance making them a favourite for engagement rings. Princess cuts are a great choice for individuals who appreciate the qualities of round brilliants, but prefer a square or rectangular shape. The Princess cut is classic and elegant, with sharp corners delivering a contemporary feel. Assess the length-to-width ratio to determine what the diamond will look like when viewing it from above. Here are length-to-width ratios as princess-cut diamonds can vary greatly in how square or rectangular they are.

What makes the emerald shape different is the cut with rectangular facets that creates a unique optical appearance.  This shape highlights the clarity of a diamond and as one of the least ‘sparkling’ shapes, the Art-Deco influence means it excels in understated brilliance with vintage glamour.

Favoured by style icons, the emerald cut has broad flat planes which highlight clarity and the natural crystalline growth of the diamond. Unlike many other cuts, this shape will reveal an inclusion easier than a more faceted shape. The emerald cut comes in many dimensions, ranging from square (the ‘Asscher’ cut) to oblong. To find the shape of emerald diamond you want, look for the length-to-width ratio to determine the diamond’s outline of what it looks like when viewed from the top.

The pear shape has 57-58 facets and this modified brilliant cut is also called a pendeloque or teardrop cut. With its single point and rounded end, the pear shape cut offers remarkable flexibility and choice. The unique look of the pear shape makes it a popular choice for a variety of jewellery especially when used as a pendant or ring.

There is quite a variation in proportions, from slender oblong shapes, to a pear shape with ‘wide shoulders’. The pear, or teardrop is a unique and feminine shape, see the diamond before you buy and make sure the cut is not too shallow as it will lack sparkle.

The marquise diamond is a modified brilliant but with 55 facets and can maximise carat weight, giving you a much larger-looking diamond. Beautiful shape when set in-line with the finger as the length of the marquise diamond makes fingers appear longer. Carefully select the dimension of marquise you want, looking out for the length-to-width ratio to determine the diamond’s outline.

An oval diamond has beautiful brilliance similar to a round diamond but requires less depth than a round brilliant. The oval cut is the perfect combination providing the sparkle of the round brilliant in a rarer more elongated form.

The oval shape shows more ‘visual surface’ so 2/3 of the carat weight goes into its depth. Oval diamonds are very popular as their length can accentuate long, slender fingers but avoid those that are too shallow as they will lack sparkle.

The Cushion shape is the antique-look cousin of the round brilliant and has been popular for more than a century. It is also known as “pillow-cut” and has rounded corners and larger facets to increase the brilliance. Cushion-cut diamonds are available in many dimensions ranging from square to rectangular. Be aware that many stones carry too much weight in their belly, making them appear smaller than the carat weight would suggest.

A rarer choice, the cushion cut’s large facets allow for greater light dispersion, providing a scintillating stone.

This unique shape is nearly identical to the emerald-cut, except that it is square. The Asscher-cut features a pavilion that is cut with rectangular facets in the same style as the emerald-cut. Like the Emerald, this shape highlights the clarity of the diamond.

The prismatic brilliance, and marvellous lustre combine with the optical illusion referred to as the “Hall of Mirrors” effect.

The Radiant is a square or rectangular shape with clipped or rounded corners combining the elegance of the emerald shape and the brilliance and sparkle of the round shape. The trimmed corners are the signature of this diamond, making the radiant-cut both popular and versatile

The radiant is the most brilliant of all the squared shapes. Radiant diamonds can vary in their degree of rectangularity, but assess the weight to depth ratio – a weighty diamond will result in a visually ‘small’ diamond.

The unique look of the heart-shaped diamond helps make it a distinctive choice for a variety of diamond jewellery and perfect for romantic souls. This rare and symbolic cut features 56 to 58 facets, differentiated by two rounded edges and a cleft at the top.

A heart-shaped stone requires great skill and dexterity on the part of a cutter. Make sure the heart shape actually looks like a heart for the ultimate symbol of love as the length-to-width ratio will determine the heart-shaped diamond’s outline. With the heart-shape, symmetry is paramount.

Though trillion cuts are most often used as a side or accent stone, this triangular cut delivers a bold and dramatic solitaire. With stunning brilliance and fire, it is being increasingly appreciated for its impressive effect.