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Among the 4 Cs of diamond grading, diamond cuts matter the most. Diamonds are the most breathtakingly gorgeous rocks on Earth well known for their brilliance and sparkle. However, a rough diamond must be cut skillfully and polished to bring out its best brightness, fire, and scintillation. In this guide, we'll see how and why the cut of a diamond is significant and how it affects the price of the diamond jewelry you buy.
Cut is the first of the 4 Cs. In fine diamond jewelry the diamond cut determines the quality of a diamond more than all the other Cs. A well-cut diamond means how well the facets of the stone interact with light to give the best brilliance and scintillation. A perfect and well-cut diamond has the best face-up appearance reflecting light and exhibiting more sparkle than a poorly cut one.
Cut Fact: A diamond can be cut only by another diamond!
Precise artistry and workmanship are required to fashion a diamond so that its proportions, symmetry and polish deliver the maximum return of light through the top (table) and crown, favouring higher scintillation, fire and brilliance.
A diamond of a better cut grade is more valuable than one of a lesser cut grade, even if they are of the same carat weight. The GIA lists five diamond cut grades — Excellent (Ex), Very Good (VG), Good (G), Fair (F), and Poor (P) — ranging from the best to the worst. The American Gem Society (AGS) uses a numerical scale from 0 to 10, where 0 is Ideal and ranks above the GIA Excellent.
Excellent (Ex) — AGS: 0 Ideal (I), 1 Excellent
Very Good (VG) — AGS: 2 Very Good
Good (G) — AGS: 3 and 4 Good
Fair (F) — AGS: 5, 6, 7 Fair
Poor (P) — AGS: 8, 9, 10 Poor
Of the 4 Cs of diamonds, the cut is the most difficult to assess and requires much training and experience. The cut quality is determined by how a diamond's facets interact with light. This is directly influenced by the symmetry, proportions and polish of the gemstone. Simply put, a well-cut diamond maximises the light that strikes each pavilion. When the cut is excellent, light reflects back through the crown and table instead of escaping through the lower parts of the diamond. Each diamond shape has different ideal cut ratios.
The Table is the largest and the upward-facing top facet of a cut and polished diamond. You can identify the shape of the diamond by its Table facet's shape. For instance, a round diamond has a round Table.
The Girdle is the widest edge around a diamond. The ideal diamond has a medium-thick Girdle. The Girdle also follows the shape of the diamond.
The Crown is the sloping side above the Girdle and the Pavilion is the longer slope below the Girdle. The angle and number of facets on the Crown and the Pavilion affect brilliance and scintillation.
The Culet is a tiny flat facet on the bottom end of the diamond opposite to its Table.
Diamond proportion is the ratio and size of the diamond's depth, width and table. When the diamond's cut is based on the recommended ratios between the size, angle, and shape of each facet it gets a high cut grade. If a diamond is cut too shallow or too deep, light is lost out of the sides. For example, shallower diamonds may appear large but lack the brilliance, fire, and scintillation of a diamond cut to the correct proportions.
Symmetry in a diamond refers to the size and placement of the facets. For example, a round brilliant diamond has 58 facets, a princess cut has 50 to 58, and a radiant cut diamond has 70 facets. A diamond with disproportionate facets or too many or too few facets will not exhibit the shine and brilliance of one that is cut to the correct symmetry.
Brilliance is the brightness of the reflected white light. When a diamond is cut to the right proportions, it will reflect brilliant white light through its table and crown under regular and extraordinary lighting.
The spectrum of coloured light that refracts off the diamond's table and facets is called fire. When you look at a diamond that has been cut proportionately, you will also see flashes of a colourful light spectrum in its sparkle. A diamond's "fire" refers to these flashes of colour bouncing off its surfaces.
Scintillation in a diamond refers to this sparkle and lustre. A well-cut and polished diamond exhibits a reflection of facets, a sparkle called Adamantine lustre that nothing else can replicate. A diamond with low scintillation appears dull and "lack-lustre".
Polishing a rough stone is the finishing step in the diamond-cutting process. A well-polished diamond has mirror-like surfaces that reflect light perfectly.
Diamond "cut" is not to be confused with "shape". Often when we hear of Diamond Cut, we think of round, oval, square, marquise, teardrop, etc. These are the actual shapes or forms of the cut stone. While diamond-cut is all about the facets, symmetry, dimensions and reflective qualities of the diamond, diamond-shape is about the external form or outline of a diamond.
Cutting diamonds into different shapes also requires precision and expertise, for even a beautifully shaped diamond is more valuable only when it can sparkle and reflect light in the best possible way.
The classic round brilliant cut diamonds are considered the perfect diamond shape and are the most widely used cut in diamond jewelry. This is so because the round diamonds have the best proportions, symmetry and brilliance.
Besides the round diamond, there are different diamond shapes. Other cut varieties are called fancy-shaped diamonds. A fancy diamond cut is also very popular in modern white gold and rose gold or traditional yellow gold engagement rings. Browse our engagement ring universe to discover fancy diamond shapes in rings.
A princess-cut diamond is the second most perfect shape after the round diamond. A princess-cut diamond has a square table, although rare rectangular ones exist. The princess cut gives diamonds a dazzling brilliance as they reflect light from the centre and the four corners.
We love the princess cut for its classic lines, brilliance and fire, all at a lesser price than a round brilliant. If you are a romantic and love to look edgy and stylish, a princess-cut diamond is just the stone for you.
Marquise diamonds have an elongated shape with pointed ends. This cut maximises the weight of the diamond. A marquise-cut diamond has an elegant shape and is perfect for those who want their fingers to appear longer and slimmer. With its unique shape, this shape is considered romantic and a celebration of happiness.
We love the marquise diamond for its slender and symmetrical silhouette. These beauties look great on a solitaire ring as smaller decorative stones embellish a larger centre stone.
A cushion-cut diamond may be square or rectangular. The cushion cut has corners with a rounded shape and large facets, which give it more fire or flashes of light than other diamond cuts. Due to its rounded corners, a cushion-cut diamond is also called a pillow-cut diamond. This is one of the most elegant diamond cuts sought after for its sparkle and fire.
We love the cushion cut diamond for its classic yet modern look.
An emerald-cut diamond has an elongated rectangular table with clipped corners and 6-12 step-cut facets. The rectangular facets and shape give off a sophisticated and stylish vibe with its long-line sides and clipped corners.
We love an emerald-cut diamond not only for its stylish lines but also because it scores on size — you can buy a larger emerald-cut diamond on a smaller budget.
This is a hybrid shape that combines the best of the rectangle step cut with the "brilliant cuts" of a round diamond. A radiant-cut diamond, therefore, offers both durability and brilliance, making it a better choice for those who enjoy an active lifestyle. For the same reasons, a radiant-cut diamond is an excellent choice for an engagement ring.
We love the radiant-cut diamond for its intense sparkle, durability, and value for money — it looks larger than most other diamonds with equal weight.
Wear a pear-shaped diamond on your finger or as a pendant, and you will surely grab attention. This eye-catching cut, also called the teardrop shape, gives the diamond 8% more surface area than a round brilliant diamond, meaning it will appear larger and cost less than its round brilliant sister! These beauties also score for their versatility; they look great on modern-, classic- or vintage-style rings.
We love the pear-cut diamond for its teardrop shape, brilliance and symmetry and, when set in an engagement ring, for its ability to make your fingers look long and slender!
When well-cut and correctly proportioned, an oval diamond is a gorgeous gemstone. An oval-cut diamond is also called an oval-modified brilliant diamond. The oval-cut diamond has been gaining popularity with its graceful, flowing curves.
We love oval-cut diamonds and think they look fabulous in engagement rings and diamond solitaire earrings.
An Asscher cut diamond is a modern and unique variation of the emerald cut diamond. The Asscher cut is often mistaken for the emerald cut, but the difference is simple. An Asscher-cut diamond is square, while an emerald-cut diamond is rectangular. Both have cropped corners. The Asscher cut has a remarkable square facet design that gives the diamond a beautiful symmetry. Currently, this cut is trending and has become very popular with celebrities.
We love an Asscher cut diamond for its good looks, not-so-sharp corners and brilliance that shines through from the inside of the stone.
If you think out of the box and like to stand out from "the crowd", you might love the trillion-cut diamond. This cut produces a triangular-shaped diamond with a soft sheen and an alluring brilliance. Because of its wider table, it can appear larger than its weight would suggest.
We love the trillion cut for its eye-catching uniqueness. It looks gorgeous as a solitaire in a three-prong setting. Small trillions can also be used to complement a centre stone.
As a precious symbol of love, the heart-shaped diamond is a show stealer. This cut requires precision, and a symmetrical heart-shaped diamond has perfectly balanced left and right sides that give it a full appearance.
We love heart-shaped diamonds for their unique shape and romantic symbolism. These diamonds are charming as centre stones in rings, earrings and pendants.
The baguette cut produces diamonds with a distinctive rectangular shape with 24 parallel facets. Baguettes are usually small stones used to highlight a larger centre stone. Several baguettes in a pressure setting can give the illusion of a single large diamond without a high price tag.
We love the baguette-cut diamond for its clarity and simplicity. It is truly a classic style.
Hearts and arrows is the visual effect seen in round brilliant diamonds of perfect symmetry and angles when viewed with a special magnifying viewer. A perfect round brilliant diamond will have a complete and accurate visual pattern of eight hearts when viewed through the pavilion, and eight arrows when looking down through the table! Now you know why this shape is the most romantic and the most popular one for engagement rings!
Round Brilliant (Most Brilliant); Oval, Marquise, Pear (Extremely Brilliant); Heart, Princess (Very Brilliant); Radiant, Cushion, Asscher (Brilliant); Baguette (Less Brilliant).
Rectangular step cuts (High).
All elongated shapes: Oval, Pear, Marquise, Emerald.
Heart, Round Brilliant, Princess cut.
Fancy cuts and shapes; round brilliants of lower clarity and colour grades; champagne, cognac, chocolate diamonds.
Round diamonds are rated as the Most Brilliant, followed by oval, marquise, and pear-shaped diamonds, which are considered Extremely Brilliant. Next come the princess cuts and heart-shaped diamonds, which are Very Brilliant. Then, we have the cushion, radiant, Asscher and emerald cuts rated as Brilliant. Finally, we have the baguette cut, which is considered Less Brilliant.
All the rectangular step cuts are best for high-clarity diamonds. Step-cut facets create a soft glow emanating from the stone. It's a blend of princess and emerald cuts.
The round brilliant diamond hides colour defects better than any other cut. The numerous small facets diminish any underlying colour or hue. Diamond cuts with broad facets like the emerald, oval, or pear will reveal more colour.
Elongated shapes, including oval, emerald, and extended cushion cuts are super-popular because these shapes make your hands and fingers look longer and slimmer. The pear or teardrop shape is also incredibly flattering and comes in creative settings.
The heart shape stands as the symbol of love. The round is brilliant for its inherent "heart and arrows" properties, the symbolism of the eternal circle, and never-ending love. And the princess cut is inspired by fairy tales and Disney movies!
In general, fancy-shaped diamonds cost less than round diamonds. The round brilliant cut is more expensive because more of the rough diamond is lost in the cutting process. However, the round brilliant usually wins because this cut hides colour and clarity flaws the best. So you can always buy a round brilliant diamond ring just below the magic numbers, with a slightly lower clarity and colour grading. Slightly rectangular princess-cut diamonds also tend to be lower in cost and come with an environmental advantage: they use up to 80% of the rough diamond.
Have no worries when you shop online for diamond jewelry at The Jewellery Room. Every day we have the honour of helping customers from all over the world. Our jewelry experts will do whatever it takes to find the perfect fit and size for the jewelry you're looking for. And please remember, if you are still in doubt, you can shop safely with us.
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