Beginning with the piece of rough, the manufacturer will often use laser mapping to plot out the optimum return on the stone once certain shapes and sizes have been cut, bearing in mind the weight loss incurred whilst cutting, and also ensuring to avoid any areas of poor colour or larger inclusions.
Following the designer marking out where to cut, the stone can either be cleaved (broken apart by inserting a steel blade into a small notch or 'kerf' and tapping it with an iron bar), or sawn using a phosphor-bronze saw coated in diamond dust or a laser saw.
The basic shape of the diamond will then be achieved by taking two diamonds, and rotating them against each other before the 'blocking faceting' is undertaken by a cross-worker to give the diamond its first 18 or so facets. A 'brillianteer' will then work to precisely polish the remaining facets.
For the buyer, it is the faceting that is the key point since this will bring out the diamond's ability to reflect light. The basic symmetry of the diamond does of course have a role to play, but even the slightest error by the brillianteer, and the light can be lost out of the bottom of the stone, leaving a very dull diamond. How much light is reflected back to the viewer is known as the brilliance.
But we are not just concerned with light reflection, but also refraction - that is to say how the diamond splits the light to reflect back the 7 colours of the rainbow. This is known as the diamond's fire.
Finally, how much intense sparkle the diamond has is its scintialltion. The ideal stone will have many of these pleasing flashes, spread evenly across the diamond's surface.
Ultimately, for the consumer, it all comes down to personal taste - the longer, narrower Emerald cut diamond offers masses in terms of elegance (and often fire), but isn't as reflective and 'sparkly' as the more popular round brilliant, princess and radiant cut. Fortunately, improvements in laser technology mean that new cuts are being created all the time, such as the the stunning Asscher cut which offers a square cut but with more brilliance, and the lovely Phoenix cut, which offers a rounded shape with extra bling!
Platinum ring set with a Phoenix cut diamond weighing 0.91 carat - £11,500.00
Platinum ring set with an Asscher cut diamond weighing 1.02 carat, and baguette diamond shoulders - £7,950.00
