The 4Cs

DIAMOND EDUCATION

A Cut Above The 4Cs

When purchasing a diamond, you will undoubtedly hear about the ‘4Cs’. This is the process of evaluating a diamond, based on four key factors: cut, colour, clarity and carat weight.

The 4Cs are an important starting point to choosing a beautiful diamond.

The 4Cs are an important starting point to choosing a beautiful diamond. However evaluating a diamond merely by the 4Cs is like describing your beloved on the basis of height and eye colour. Two diamonds can look the same ‘on paper’ however they can actually be very different when viewed in person. Andrew Mazzone selects diamonds for his engagement rings according to a more complex set of criteria, applying a high level of expertise that cannot be translated into any gemmological report. Diamonds are not manufactured on an assembly line. Diamonds are not interchangeable. Like you, they are unique, so every diamond selected for you to view, has passed thorough examinations in order to ensure that it outshines all others.

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Cut

FOR BRILLIANCE NOT CARAT WEIGHT

The beauty of a diamond depends on how well it has been cut, more than anything else. Understanding the cut of a diamond begins with the shape e.g. round brilliant, princess cut or emerald cut. However, in determining the value and beauty of a diamond ‘cut’ refers to its proportions, symmetry and polish not shape.

Although nature determines a rough diamond’s clarity, carat weight and colour, the hands of master craftsmen release its fire, brilliance and scintillation. When a diamond is cut to exact proportions, neither too deep nor shallow, light will reflect inside the diamond from one mirror light facet to another and reappear through the top of the stone, as if it’s radiating from within. Our diamonds are cut to exacting proportions that maximize the beauty of the stone, (even when such precision requires sacrificing more of a rough diamond’s weight.) For example a small well cut diamond will sparkle more than a large diamond cut poorly.

Cut Descriptions

1. Ideal

This grade is reserved for a round brilliant diamond. When cut to ideal proportions the diamond achieves 100% light return or total internal reflection, thus the diamond will have the maximum brightness and fire possible.

2. Excellent

This grade roughly represents the top 5% of diamond quality, based on cut. Hence it’s considered a rare, exquisite cut because it reflects most of the light that enters the diamond.

3. Very Good

This grade roughly represents the top 15% of diamond quality, based on cut. So for a lower price than the excellent cut, it reflects nearly as much light.

4. Good

This grade roughly represents the top 25% of diamond quality, based on cut. Much cheaper than a very good cut, it reflects most of the light that enters it.

5. Fair

This grade roughly represents the top 35% of diamond quality, based on cut. It’s regarded as a quality diamond but it won’t be as brilliant as a good cut.

6. Poor

The poor cousin of other grades, these diamonds lose most of their light out of the sides and bottom. This is because they are either too shallow and wide, or too narrow and deep.

Colour

Nothing Below 'H'

Diamonds are transparent, with most displaying barely perceptible hints of colour. The less colour in a diamond, the rarer it is. Diamonds are graded on a colour scale from D through to Z, based on the absence of colour. Andrew selects diamonds graded from D to H to ensure a high standard within his collection. Diamonds range from completely colourless to near colourless. Fancy coloured diamonds are an exception and are highly sought after due to their extreme rarity – particularly yellows, pinks and blues. Quality is judged by the intensity of their hue, and unlike white diamonds, the more colour, the rarer they are.

Grading

GIA (Gemological Institute of America) is the international industry standard; diamond D-to-Z colour-grading scale is the industry’s most widely accepted grading system, which is actually based on the absence of colour. The colour of a diamond refers to the relative amount of yellow, brown or grey body colour that a stone possesses. The GIA scale starts at ‘D’ and ends at ‘Z’, with ‘D’ being void of any body colour, and ‘Z’ having a light yellow, brown or grey colour.

Many of these colour variations are so subtle that they are invisible to the untrained eye, however they certainly affect diamond quality and cost. For example, a perfect diamond rated ‘D’ has no hue, which makes it more highly valuable.

Clarity

Clean to the Naked Eye

Virtually all diamonds contain identifying characteristics, most of them too small to be seen with the naked eye. These ‘inclusions’ are nature’s birthmarks; when viewed using magnification they look like tiny crystals, clouds or feathers. To determine a diamond’s grade of clarity, a gemmologist will consider the size, number, position, colour and general nature of any inclusions. Diamonds exhibiting no such inclusions, are categorised as flawless (FL) or internally flawless (IF). In general, the greater the number and size of inclusions within a diamond, the lower the clarity grade.

Grading

GIA’s clarity grading system was established to avoid the use of misinterpreted terms such as ‘loupe clean’ or ‘piqué’. Today, terms such as VVS1 or SI2 are common in ‘diamond’ language. Just to be clear, ‘clarity’ refers to the presence and visual appearance of internal characteristics of a diamond called ‘inclusions’, and surface defects called ‘blemishes’.

Carat

IT's not just about weight

The size of a diamond is measured in carat weight, which is commonly expressed in points. Each carat equals 100 points or 1/5 of a gram. Larger diamonds are valued because they are found less frequently in nature. However diamonds of equal carat weight may vary greatly in brilliance, depending on their proportion and cut. Therefore carat weight alone is a poor guide for value. It is a complex combination of cut, colour, clarity and carat weight that determines a diamond’s quality and beauty.

One carat (ct.) equals 200 milligrams in weight.

Each carat is divided into 100 points e.g. 1/2 ct. = 50 points

A perfectly cut 1 carat diamond’s actual size varies significantly in different shapes:

Round Brilliant: 6.5mm
Princess Cut: 5.5mm x 5.5mm
Cushion Cut: 5.5mm x 5.5mm
Emerald Cut: 7mm x 5mm
Pear Cut: 8mm x 5.5mm
Oval: 7.5 x 5.5mm
Marquise Cut: 10mm x 4.75mm

Shape

Diamond shape refers to the geometric appearance of a diamond. Diamond shapes are categorised into two grounds: round diamonds and fancy shape diamonds. Round diamonds, also known as round brilliant cuts, are the most traditional shape. Fancy shape diamonds refer to any diamond that is not a round brilliant.