Stone Guide
Every diamond we have worked with over the years has brought a unique experience to the benches of H.G.Bespoke. The reason is that no two diamonds will appear the same visually, even those with identical grades on their stone report. Therefore, while it is important to view stones in regards to their specific structural grades, often referred to as the ‘Four Cs’ it is equally as important to physically view the stones in person.
A diamonds grading certificate or report will have been created in laboratory conditions, often removed from the artistic side of the jewellers’ creative processes, and a such offer the client a more sterilised view of the stone’s material/financial parameters. While the report can give you a reasonable guideline with which to initially select potential stones for your piece, it is only in the physical face-to-face viewing stage that each stone’s real-world beauty becomes apparent.
The Four C's
The Four Cs of a diamond are generally only applicable, in full, to Round Brilliant-cut diamonds, and they are Cut, Colour, Clarity, and Carat. Fancy shapes, such as Pear, Oval, Heart, etc do not have a cut grade on their grading reports.
Cut
Firstly ‘Cut’ is perhaps the most important of the Four Cs. Cut does not refer to a diamond’s shape as such, but rather to the quality of workmanship; regarding the stone’s proportion (how round it is) and arrangement of facets, for round brilliant diamonds. The quality of a diamond’s cut will determine the amount of brilliance, scintillation, and fire that a diamond shows. Grades for cut range from ‘Excellent’ through to ‘Poor.’

Colour
Next is the stones ‘Colour.’ Colour measures a diamond’s absence or presence of visible colouring. This is because most “colourless” or “white” diamonds contain trace amounts of nitrogen (yellow diamonds), nitrogen/nickel and ‘Latice Distortion’ (brown diamonds) or in the case of grey type diamonds the addition of high concentrations of hydrogen, and occasionally boron.
The less colour in a diamond means there are fewer impurities or trace elements, which increases the stones value. There are 23 colour grades for diamonds that start on a scale from D-to-Z, with D being a diamond has no detectable colour, and Z being a diamond that has a light but obvious visible colour. Once a diamonds colour goes beyond Z it is classed as a ‘fancy’ colour diamond. These fancy colours are evaluated on a different scale, for both colour and exponential cost.
Over the years we have shown on social media how we see the colour in a diamond, while evaluating a stone for our clients, by using a colour card and placing the diamond face down. This allows you to see the stones colour rather than be blinded by the stones sparkle. Generally, for most untrained people you will need between one- or two-colour grades difference between the stones shown; before you might notice an obvious visible difference, as the colour grade from one stone colour to the next is extremely subtle. This can often impact a client’s original requests for more expensive ‘high coloured’ stones, when they realise they can go one or two colours lower to achieve a larger stone than their budget would originally have suggested to them. We believe knowledge is very important when choosing your stone!

Clarity
After colour comes Clarity. Clarity measures the number, size, and position of internal ‘inclusions’ and external ‘blemishes’ visible in diamonds. Inclusions are shown on a stone’s grading report and include small crystals or fissures within the diamond. Blemishes can include chips, indents, and ‘Naturals’ which are remnants of the stone’s original external surface. Some ‘Naturals’ are both desirable and unique, such as Trigons, and give a unique fingerprint to your stone that sets it aside from any other.
Clarity grades range from ‘Flawless,’ which means a diamond has no visible imperfections at 10x magnification either inside the stone’s structure or on its surface, to ‘Included,’ where a diamond contains a significant number of highly visible imperfections. Diamonds with grades down to VS2 (Very Slightly Included) or SI1 (Slightly Included) do not typically have eye-visible inclusions, and will be labelled as ‘Eye Clean’. Diamonds of I1 clarity (Included) or lower have inclusions that are easily seen by the naked eye, and are less viewed as much less attractive. Some of the lower-level inclusions might also impact the diamond’s durability in every day wearing conditions.

Carat
The final ‘C’ is Carat, which refers to a diamond’s physical weight. In most cases the higher the carat weight, the larger the diamond appears and the more valuable the stone. Though certain of the other grades on a diamond report will affect this, such as the stone’s Symmetry. As an example of this, a one-carat diamond that is wider; or spreads and has shallow depth, will appear larger than a one-carat diamond with excellent or ideal proportions.
The carat of a stone, along with the colour, clarity, cut, polish, symmetry, and other peripheral grades such as fluorescence, and measurements relating to depth and table percentages will be used to ascertain a diamonds cost per carat on a trade wide listing.

Conclusion

While our available stones listings allow you to browse a vast selection of diamonds, some of which that have 360degrees videos, at H.G.Bespoke we still insist on first time clients coming to the workshop to physically view a handful of chosen stones. While a stone may look good on paper, the way that stone ‘works’ in real life is often one of the most important parts of choosing the right stone for you, both in fulfilling your budget and the needs of your preferred design.
Coming to the workshop in Hatton Garden, will allow you to view your chosen stones in several different lighting conditions, without being compelled to buy. You will have access to our Master Ring Maker, who can assess the make of the stone (a combination of the stone’s Cut, Symmetry, and proportions) to ensure that during the mounting process your chosen stone will be able to have its very best elements brought forward, so that once on your hand your investment will look its very best.
Our diamonds will come from one of the main laboratories at GIA, HRD, or IGI. However, in some cases, such as any H.G Historical pieces (stones brought in second hand) will be old enough to predate the diamond report process. With these historical stones we can offer to send your purchase to GIA New York, or HRD Antwerp for the stone to be graded after a sale. The cost for this would be added to the cost to mount your stone. All of our new listed stones come with assurances of being from guaranteed conflict free sources
Unfortunately, we do not sell stones to be taken elsewhere for manufacture, so all H.G.Bespoke diamonds will have to be made into H.G.Bespoke pieces at some point. This ensures the generous time spent with you in choosing your perfect stone does not detract from the artistically important manufacturing side of the business.
If you have any questions regarding choosing your perfect diamond, please contact us to get your questions answered.