A diamond can take on many different shapes. The most common and popular form is undoubtedly the round cut brilliant. Additionally there are various fancy shapes: the marquise (or navette), the pear, the oval, the emerald, the princess (square) and the heart shape.
The invention of modern diamond polishing is generally contributed to the Flemish jeweller, Lodewyk van Berquem (Bruges), who lived in the 15th century. Van Berken invented a polishing wheel, called the scaif, using olive oil and diamond dust. This relatively simple instrument revolutionized the diamond cutting industry. Since then, it was possible to symmetrically polish the facets of a diamond and in angles that maximized scintillation.
The modern brilliant cut diamond is without a shadow of a doubt the most popular shape available. It consists of 58 facets and the shape is optimized to reflected the light entering the stone through the top (table). The cut surfaced in the mid 17th century and counted only 17 facets in the crown. Later, a Venetian cutter called Vincent Peruzzi, improved the shape to 33 facets in the crown.
The princess cut is the second most popular diamond cut (the brilliant cut being the most popular). This cut, also referred to as a square modified brilliant, is relatively new. Unlike most square or oblong shapes, the facets are brilliant cut. Because of this, princess cut diamonds have more scintillation and fire than traditional step cut stones.
The pear is a brilliant-cut diamond in the shape of a teardrop: a single point and rounded end. Its a popular choice for a variety of jewellery, most notably pendants and earrings. By choosing an elongated pear shape, the lenght of the fingers is accentuated. For a traditional pear-shaped diamond, the length-to-width ratio should be around 1.5:1.
The emerald cut, also referred to as step cut or table cut, is a basic/fundamental cut (like the brilliant cut). Unlike the facets in the brilliant cut, the facets of the emerald are cut in steps: stripe-like facets, which run parallel to the girdle. The corners are truncated, this is done to protect the stone. Sharp edges and points are vurnerable and risk getting chipped. The emerald cut is often used in colored stones because light is better reflected and color is intensified.
Cushion cuts were at the height of their popularity during most of the nineteenth century. The basis for the cushion-cut is the Old Mine Cut, a square cut with rounded corners, a high crown, smallish table and large facets. The modern cushion cut has a square shape consisting of 64 facets which are placed in an angle to maximize depth of the gemstone (note the difference with the modern brilliant cut, which maximizes the reflection of light towards the eye).
The particular cut of a stone is mostly a pragmatic choice. The shape of the uncut, rough diamond gives the first indication of the most efficient cut/shape. Cutting a round stone out of an oblong rough diamond, would we very wastefull. A suitable shape for this situation is the marquise. Having roughly the same amount of facets as the brilliant cut, the marquise is more difficult to cut because of the fragile, sharp points.
Diamonds are formed under extreme physical conditions and because of this, no diamond is free of imperfections. These imperfections can impede the passing of light through the diamond and therefore lessen the brightness of a stone. However, minor inclusions can be useful since they can contribute to the unique character of a diamond. Flaws are examined by experts under 10x magnification and can be divided under tzo categories: internal characteristics or inclusions and external characteristics or blemishes.
FL - Flawless
No inclusions or blemishes are visible to a skilled grader using 10× magnification.
IF - Internally Flawless
IF diamonds are free from internal characteristics/inclusions when examined under 10x magnification. A diamond is not disqualified from the Loupe Clean grade if internal graining is not reflective, white or coloured and does not significantly affect transparency.
VVS1 - Very, Very Slightly Included 1
VVS1 diamonds contain minute internal characteristics/inclusions. These are extremely difficult to observe when examined under 10x magnification.
VVS2 - very, Very Slightly Included 2
VVS2 diamonds contain minute internal characteristics/inclusions which are very difficult to observe when examined under 10x magnification.
VS1 - Very Slightly Included 1
VS1 diamonds contain minor internal characteristics/inclusions which are difficult to observe when examined under 10x magnification.
VS2 - very Slightly Included 2
VS2 diamonds contain minor internal characteristics/inclusions which are somewhat easy to observe under 10x magnification.
SI1 - Slightly Included 1
SI1 diamonds contain noticeable internal characteristics/inclusions which are easy to observe when examined under 10x magnification.
SI2 - Slightly Included 2
SI2 diamonds contain noticeable internal characteristics/inclusions which are very easy to observe when examined under 10x magnification.
I1 - Included 1
I1/P1 diamonds contain internal characteristics/inclusions which are prominent when examined under 10x magnification. They are also visible face up to the unaided eye. Under certain circumstances, internal characteristics/inclusions may also be visible face up to the unaided eye in higher grades. These diamonds can also be calleD Piqué 1.
I2 - Included 2
I2/P2 diamonds shall contain internal characteristics/inclusions which are very prominent when examined under 10x magnification. They are also easily visible face up to the unaided eye, slightly reducing the brilliancy of the diamond. These diamonds are also called Piqué 2.
I3 - Included 3
I3/P3 diamonds contain internal characteristics/inclusions which are extremely prominent when examined under 10x magnification. They are also very easily visible face up to the unaided eye, reducing the brilliancy of the diamond. These diamonds are can also be called Piqué 3.
In the context of diamonds, colour is something the buyer does not want to see. The less visible the colour, the higher the value of the diamond; although the opposite is true for fancy-colour diamonds. The most common grading system used, is that of GIA. Using a colour-system ranging from the letter D (100% colourless) to the letter Z (near-colourless), this scale defines a well defined spectrum of all possible colours within a diamond. The difference between colours are often very subtle and usually not visible to the untrained eye. It will however have a significant impact on the pricing of the stone.
Although the most common grading system used is that of GIA, there are different organizations that also grade diamonds, such as: the American Gem Society (AGS) which uses the electric calorimeter, the International Diamond Council (IDC) and Scandinavian Diamond Nomenclature (Scan D.N). To be complete, we have also listed the different gradings systems as well.
D - Colourless/ Exceptional White+
This is the highest color grade a diamond may recieve, the diamond is then 100% colorless. These diamonds are extremely rare and also heavily priced. An alternative name used for this colour is 'River' in Scan. D.N and has a value of 0-0,49 on the electronic calorimeter.
E -Colourless/ Exceptional White
E colour diamonds are very bright and white. They display virtually no color. Its alternative name in Scan. D.N is also 'River' and has a value of 0,5-0,99 on the electronic calorimeter.
F - Colourless/ Rare White+
These are exceptionally transparent and also very rare and highly priced. It is very difficult to find traces of color in E or F graded diamonds, especially to the untrained eye. In Scan. D.N. This color is called Top Wesselton and has a value of 1,00-1,49 on the electronic calorimeter.
G - Near Colourless/ Rare White
Only when these diamonds are held next to a master stone of higher color grade, can a slight color be detected. Otherwise color is nealry indiscernible. Although these diamonds are still rare, they are slightly less expensive and are considered a good value. In Scan. D.N. G diamonds are called Top Wesselton and has a value of 1,5-1,99 on the electronic caloriemeter.
H - Near Colourless/ White
H diamonds contains noticeable colour only when it is being compared to higher color diamonds. These diamonds are considered a good value. In Scan. D.N. These diamonds are called Wesselton and have a value of 2,0-2,49 on the electronic calorimeter.
I-Near Colourless/ Slightly Tinted White+
Slight color in these diamonds are detectable. However, once the diamond is mounted, the color is unnoticeable to the untrained eye. The majority of these diamonds are used for engagement rings, earrings and pendants, due to it's good value. In Scan. D.N. they are called Top Crystal and have a value of 2,5-2,99 on the electronic calorimeter.
J -Near Colourless/ Slightly Tinted White
J diamonds have a slightly noticeable color but still appears colourless to the untrained eye. In Scan. D.N. they are called Crystal and have a value of 3,0-3,49 on the electronic calorimeter.
K -Faint yellow/ Tinted White+
K diamonds have a yellow tint that is more easily detected by the untrained eye. Due to its noticeable color, the price of a K diamond is often half the price of a G diamond. In Scan. D.N. the diamond is called Top Cape and has a value of 3,5-3,99 on the electronic calorimeter.
The exceptional brilliance and visual appeal of diamonds is, above all, the result of the cut: the relationship between the various components of a stone (the dimensions of and the angles between the facets), the symmetry of a stone and its polish. Cut should not be confused with the shape of a diamond (the silhouette seen from the top).
3 x Excellent
Tablesize between 54 and 62%, Crown height between 12 and 16%, Pavilion depth between 43 and 44.5%
Tablesize between 52 and 53% or between 63 and 66%, Crown height between 11 and 11.5% or between 16.5 and 18%, Pavilion depth between 41.5 and 42.5% or 45%
Tablesize between 50 and 51% and between 67 and 70%, Crown height between 9% and 10.5% or between 18.5 and 19.5%, Pavilion depth between 40 and 41% and between 45.5 and 46.5%
Tablesize up to 49% and upward of 71%, Crown height up to 8.5% and upward of 20%, Pavilion depth up to 39.5% and upward of 47%
A poor cut grade is assigned when either polish or
symmetry is poor.
With Side Stones
Can be Classic-, Cathedral-, Contour-, Knife Edge-, Trellis- setting
pavé in line
Pavé Castel Setting
Fancy Color diamonds are valued using different criteria than those used for regular diamonds. When the color is rare, the more intensely colored a diamond is, the more valuable it becomes. Another factor that affects the value of Fancy-Colored diamonds is fashion trends. For example, pink diamonds fetched higher prices after Jennifer Lopez received a pink diamond engagement ring. Extremely low grade quality has not stopped creative merchants from marketing for example Dark Brown diamonds as so-called chocolate diamonds.
Fancy-colored diamonds such as the deep blue Hope Diamond are among the most valuable and sought-after diamonds in the world.