Diamonds are forever. Diamonds are a fascination. They evoke feelings of wonder and awe in the eyes of some and romance in the hearts of others.
This article below serves as a crash course in understanding the different aspects that makes a diamond what it is. I hope you’ll be somewhat educated by the end of it 🙂
Cut
Cut refers to the angles and proportions of a diamond. It is the only one of the 4Cs that is influenced by the human hand.
Diamond cutting requires great skill and training. The cutter must polish tiny surfaces known as facets onto the rough diamond. This process is what creates the facets known as the crown, culet, table, girdle and pavilion of the diamond.
To cut a diamond perfectly, a craftsman will often need to cut away more than 50% of the rough diamond.
A well-cut diamond will internally reflect light from one mirror-like facet to another and disperse and reflect it through the top of the gem. The facets, when arranged in precise proportions, will maximize the fire life and brilliance of a diamond.
A well-cut diamond will be higher in quality and value than deep or shallow-cut diamonds. Diamonds that are cut too deep or too shallow lose or leak light through the side or bottom, resulting in less brilliance and a less valuable stone.
Cut also refers to the shape of a diamond – round, square, or pear, for example.
Round diamonds are symmetrical and capable of reflecting nearly all the light that enters, so it is the most brilliant of all diamond shapes and follows specific proportional guidelines.
Non-round shapes, also known as ‘fancy shapes’ have guidelines in order that they are considered to be well-cut.
Carat
Carat refers to the weight of a diamond.
Often mistaken with size, carat it is actually a measure of weight.
The term carat is a derivative of the word carob. Carob seeds, which are surprisingly uniform in weight, were used as a reference for diamond weight in ancient civilisations. One carob seed equalled one carat.
One carat is equivalent to 200 milligrams. One carat can also be divided into 100 ‘points’. A .75 carat diamond is the same as a 75-point or 3/4 carat diamond.
Since larger diamonds are found less frequently in nature, a single 1-carat diamond will cost more than two 1/2-carat diamonds, assuming the colour, clarity and cut are the same.
Cut and mounting can make a diamond appear larger or smaller than its actual weight. A diamond’s setting should always optimise its beauty.
Color
Colour refers to the degree to which a diamond is colourless.
Diamonds can be found in many colours, however white-coloured or colourless diamonds remain the most popular.
Diamonds are graded on a colour scale which ranges from D (colourless) to Z. Warmer coloured diamonds (K–Z) are particularly desirable when set in yellow gold. Icy winter white coloured diamonds (D–J) look stunning set in white gold or platinum.
Colour differences are very subtle and it is very difficult to see the difference between an E and an F, for example. Therefore, colours are graded under controlled lighting conditions and are compared to a master set for accuracy.
Truly colourless stones, graded D are treasured for their rarity. Colour, however, is subjective. The Incomparable, one of the world’s most beautiful diamonds, contains hints of brown, smokey amber and champagne colours.
Nature has also created diamonds in shades of blue, green, yellow, orange, and pink. Red is the rarest of all. These diamonds are called ‘coloured fancies’ and are extremely rare and highly treasured.
Clarity
Clarity refers to the presence of inclusions in a diamond.
Naturally-occurring features called inclusions provide a special fingerprint within the stone. Inclusions are natural identifying characteristics such as minerals or fractures, occurring while the diamond was being formed in the Earth.
The majority of these natural birthmarks are invisible to the naked eye, yet they affect the way light is reflected and refracted within the stone.
Inclusions appear as different shapes, such as crystals, clouds or feathers. These idiosyncrasies often add to the overall character of the diamond.
Containing several birthmarks or inclusions, the Excelsior is considered one on the world’s most beautiful diamonds.
Most inclusions are not visible to the naked eye unless magnified.
To view inclusions, gemologists need to use a magnifying loupe that allows them to see a diamond at 10x its actual size.
Inclusions are ranked on a scale of perfection, known as clarity. The clarity scale, ranging from F (Flawless) to Included (I), is based on the visibility of inclusions at a magnification of 10x.
Even with a loupe, the birthmarks in the VVS (Very, Very Slightly Included) to VS (Very Slightly Included) range can be very difficult to find. It is only when a diamond is graded ‘I’ that it is possible to see the birthmarks with the naked eye.
The position of inclusions can affect the value of a diamond and you should consider the number, size, brightness, nature and position of inclusions.
Some inclusions can be hidden by a mounting, and have little effect on the beauty or brilliance of a stone. An inclusion in the middle or top of a diamond could impact the dispersion of light, sometimes making the diamond less brilliant.
There are very few flawless diamonds found in nature, making these diamonds much more valuable.
Diamonds anyone? 🙂
Source: DeBeers
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