Rather than describing the shape of a stone, cut refers to the proportion, symmetry brilliance and polish of a diamond. This means that the diamond cutter has taken into account the inherent characteristics of each individual stone and chose the best way to shape it to accentuate its beauty.
It is very essential to know diamond anatomy before understanding cut.
Diameter: Width of a diamond measured through the Girdle.
Table: Largest facet of a gemstone.
Crown: Top portion of a diamond extending from the Girdle to the Table.
Girdle: Intersection of the Crown and Pavilion which defines the perimeter of the diamond.
Pavilion: Bottom portion of a diamond, extending from the Girdle to the Culet.
Culet: Facet at the tip of a gemstone. The preferred Culet is not visible with an unaided eye (graded “none” or “small”).
Depth: Height of a gemstone measured from the Culet to the Table.
A diamond gets its brilliance and scintillation by the cutting and polishing of its facets, allowing the maximum amount of light that enters through its top to be reflected and dispersed back through the top.
Cut has the following 3 components:
DIAMOND CUT BY SHAPE
Cut is the appraisal of the diamond’s facets and the ability of these to transmit light and sparkle. A diamond cut by shape describes the outline of the stone and pattern of the facet arrangement. Did you know that over 75% of all diamonds sold are round brilliant cut?
The most popular and stylish shapes are defined as: ROUND, PRINCESS, EMERALD, PEAR, RADIANT, MARQUISE, CUSHION, HEART, OVAL, ASSCHER.
The Round Brilliant Cut diamond is the most traditional and popular of all the diamond shapes. Many experts consider this shape ideal for a diamond because it maximizes its sparkle. It has 58 facets: 1 table, 8 bezel facets, 16 upper-girdle facets on the crown, 8 pavilion facets, 16 lower girdle facets, and usually a culet on the pavilion. This shape of diamond is most commonly used in solitaire diamond engagement rings.
Second only to the round brilliant diamond in popularity is the square-shaped princess cut diamond. Originally patented as the Quadrillion diamond, this versatile shape can stand alone as a solitaire, or make a real statement with shoulder accents or a diamond-set band. The ideal princess cut will have length to width ratio is as close to 1.00:1.00 as possible, as princess cut diamonds can range from this perfect square through to almost rectangular. When choosing a princess cut diamond, be on the lookout for girdles which are extremely thin and can be prone to chipping.
The Emerald Cut diamond is a square or rectangular shaped stone with cut corners. This is also known as Step Cut because it has rows of facets, usually 48 to 50, that resemble a staircase. Due to its larger, more open table, this shape highlights the clarity of a diamond but with fewer facets brings less brilliance than the other shapes.
The Pear Cut diamond is often called a teardrop due to its single point and rounded end with 56 to 58 facets. This shape is popular for its uniqueness and brilliance. Pear Shape diamond is mostly used in pendants and also a good choice for a hand with smaller fingers.
The Radiant Cut is a rectangular or square stone with cut corners. This shape comes with 62 to 70 facets and offers the elegance of the emerald shape with the brilliance of the princess shape. Trimmed corners are the signature of this shape, and they help to make the radiant cut a popular and versatile choice for jewellery. Diamonds with radiant shape look very good when adorned with baguettes or round side stones.
The Marquise Cut is a traditional shape having elongated ends at both edges. The pointed ends make this shape the most fragile and the most expensive of brilliant style cuts. It has a total of 56 facets, construction of which requires a lot of experience and the delicacy of its sharp points demands utmost precaution. Now-a-days this shape is very popular for engagement rings.
Cushion Cut diamonds are also known as “pillow cut” diamonds. This shape ranging from square to rectangular and it has rounded corners and larger facets to increase its brilliance. These larger facets also highlight the diamond”s clarity.
The human heart is the ultimate symbol of love and the Heart Cut is regarded as the most romantic of all the shapes. The Heart shaped diamond is essentially a pear-shaped diamond with a cleft at the top and it typically contains 59 facets. Due to the complexity of the shape, skilled cutting is necessary to maintain the diamond’s brilliance. Generally people prefer a heart shape diamond for sentimental purposes. This shape is mostly used in pendants, but also suitable for most jewellery items.
The Oval Cut is also a beautiful shape and provides great brilliance and fire through its 56 facets. A well cut Oval shaped diamond can be almost as bright as a well cut Round Brilliant shaped diamond.
The Asscher Cut is a modified version of the Emerald Cut. This shape is named after Joseph Asscher of Holland who was an eminent diamond cutter. In 1902, his company, Asscher Diamond Co., developed and patented the Asscher Cut, a squarer step cut with an almost octagonal outline. This new cut enhanced the fire and light of the stone; it had a small table, a high crown, wide step facets, a deep pavilion and square culet.
The Trilliant Cut is one of the unusual cuts and the diamond with this shape displays a very sharp brilliance or fire. This triangular shaped diamonds may either have pointed corners or more rounded corners.
DIAMOND CUT BY DEPTH
With proper cutting (diagram 2 below) the light passes through the top, bounces off the sides, and then travels back out the top, giving the diamond optimum brilliance. If the diamond is cut too deep (diagram 1), light passes through the side of the diamond. If the diamond is cut too shallow (diagram 3), light passes through the bottom of the diamond, also inhibiting maximum brilliance.
A poorly cut diamond will lack the lustre and glow of its premium-cut counterparts, and for this reason, master diamond cutters will often sacrifice carat weight to improve the cut of a stone.
DIAMOND POLISH AND SYMMETRY
Polish and symmetry are two important aspects of the cutting process. The diamond polish expresses the smoothness of the diamond’s facets where as the symmetry refers to alignment of the facets. A poor diamond polish, or rough facets, can diminish a diamond’s brilliance, as well as its value.