HOMEA Survivor's Guide to Buying a Diamond
Before starting to shop for diamonds or diamond jewellery, it is interesting and important to have a basic idea of the different aspects of diamond quality – what it is that makes the best diamonds. Armed with this knowledge, you will be much better placed to make a good value-for-money purchase and obtain a diamond that has the particular qualities that you are looking for.
Shape
This is the first decision to make. Round diamonds are by far the most popular but several other shapes are available.
Round
The round brilliant cut diamond is the most researched diamond shape available. Much work has gone into cutting calculations and techniques over the last 100 years in order to optimize the fire and brilliance in a round diamond. It also gives a greater flexibility in balancing grades of colour and clarity while still obtaining the fire and brilliance required.
Princess
Traditionally square or rectangular in shape with pointed corners, this is the most popular non-round shape and a favourite for engagement rings.
Emerald
The pavilion of the emerald differentiates it from other shapes. This is cut with rectangular facets to create a unique optical appearance. Its larger, open table highlights the clarity of the diamond.
Asscher
A shape very similar to the emerald-cut except that it is square. This beautiful diamond has a pavilion that, like the emerald, is cut with rectangular facets.
Oval
This shape has a wonderful brilliance similar to the round diamond. It is popular in rings as the length can accentuate the slenderness and length of the finger.
Marquise
Like the oval, this shape makes the finger appear long and slender. It is also one which can maximise carat weight, making the diamond appear larger.
Pear
Also known as the teardrop, this shape with it’s single point and rounded end is a popular choice for a variety of diamond jewellery.
Radiant
Trimmed corners are the significant feature of this diamond making it a popular and versatile choice for all styles of jewellery. Radiant cut can vary from square to various degrees of rectangularity.
Cushion
Also known as 'pillow-cut' diamonds, this unique shape has been a popular choice for over a hundred years. It has rounded corners and its larger facets increase its brilliance and highlight its clarity.
Heart
The beautiful appearance of the heart-shaped diamond and it’s being, of course the ultimate symbol of love, make it a distinctive choice for a wide variety of diamond jewellery.
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Having dealt with the different shapes of diamond available, we come to the other important aspects of diamond buying – carat, colour, cut, clarity, certification and care.
Carat
The weight of a diamond is measured in carats – it is important to remember that it is not a measurement of size. A diamond of say 2 carats will not appear to be twice the size of a 1 carat diamond. Out of all the various diamond characteristics, the weight has the greatest impact on the price and owing to the fact that larger diamonds are relatively scarce; the increase in price will be disproportional to its weight increase. Hence a diamond which is say twice the size of another may be four times the price. For this reason, some diamonds will have poor cut to retain more diamond rough and hence a larger carat size and selling price. However, this same diamond with it’s poor cut and maybe colour and clarity also will be less eye-catching than a smaller one with excellent cut, colour and clarity. Therefore the right balance is important – size isn’t everything! The popular carat sizes are 0.50ct, 0.75ct, 1.00ct, 1.50ct and 2.00ct.
At one time, having a 1.00ct diamond was much desired with little regard to quality but in recent times more emphasis is being placed on cut, clarity and brilliance.
Colour
The Gemmological Institute of America (GIA) created the Diamond Colour Scale in the 1950s to give definition to the colour spectrum of diamonds. The scale starts at D and continues through to Z becoming progressively more yellow towards the end of the alphabet. GIA Colour-grading Scale
D.E.F.
Diamonds in this range are colourless, very rare and demand premium prices. They are regarded as 'collection' colours because of their scarcity and amazing whiteness. The unaided and untrained eye would find it extremely difficult to distinguish between these three grades.
G.H.I.J.
This range is classed as near-colourless, G and H being the more desirable and termed as 'rare white diamonds'. The whole group represent very good value. As one would expect, colours I and J, being slightly warmer consequently command lower prices. Our advice would be to buy H and above if possible unless price or carat weight demand otherwise.
K to Z
These grades display visible signs of yellow colour and whilst they are excellent in brooches and alternative jewellery are not in demand for the diamond solitaire engagement ring and similar settings.
Flourescence
This is often a matter of personal preference; some people actively seek those diamonds which display this unique effect whilst others definitely avoid it. Fluorescence is graded from feint to very strong with very strong having the ability to add an even whiter appearance to an already near-colourless diamond. On the negative side it can give the diamond a slightly hazy appearance.
Cut
The brilliance of a diamond is determined by its cut. It is generally considered by gemmologists that it is the most important characteristic of a diamond as one with a poor cut, even though it has excellent clarity and colour will exhibit a dulled brilliance.
Diamond Anatomy
Diamond Symmetry
The width and depth of a diamond and the alignment of its facets greatly affects how light enters, travels within and then exits the diamond in the form of brilliance.
As shown above, a diamond with too shallow a cut will lose light from the bottom. One that is too deep will lose light from the sides: in both cases the diamond will lose brilliance. The well-cut diamond will reflect its light upwards in the form of sparkle and brilliance. For the most beautiful diamonds, look for a symmetry grade of ID (ideal) or EX (excellent) VG (very good) or G (good).
Diamonds with grades of F (fair) or P (poor) should be avoided as the alignment of their facets may course the misdirection of light to an extent that the brilliance of the diamond will be adversely affected.
Diamond Polish
This refers to the quality of the finished surface of the diamond faces and, like symmetry, is graded from ID or EX, VG, G, F and P. Obviously the top grades perform the best in terms of appearance and brilliance, VG or G represent good value and performance whereas with F or P, the surface of a facet can be dulled and may create blurred or dulled sparkle.
Clarity
The most sought after diamonds are those which are absolutely clear, free of any scratches, tiny characteristics or trace minerals that can detract from their purity and beauty. Those diamonds are the rarest and consequently the most expensive. Diamonds are graded to reflect their clarity as follows:
FL or IF Diamonds
These are very rare and beautiful diamonds. FL = flawless; no internal or external flaws. IF = internally flawless.
VVS1 & VVS2 Diamonds
VVS = very, very slightly included. Those are excellent quality diamonds where the imperfections are very difficult to see even under 10 x magnification.
VS1 & VS2 Diamonds
VS = Very slightly included. The inclusions are not normally visible to the naked eye but their lower price makes them excellent value diamonds.
SI1 & SI2 Diamonds
SI = slightly included. With these diamonds, the inclusions are visible using 10 x magnifications and may also be visible to the naked eye. However, they are still good-value diamonds.
I1, I2 & I3 Diamonds
These are all very poor clarity diamonds with the inclusions being visible to the unaided eye. These grades lose light return as the inclusions are sometime so large that light entering the diamond can be refracted at random angles. The gems are also less durable. These diamonds are only suitable where size is the all important factor and colour and cut can be sacrificed maybe because of budget. To sum up, the FL/IF grade diamonds are obviously the most desirable, but, being the very best are also very expensive. The best-value buy is what is known as the "eye-clean" diamond, typically the VS grades which do not contain visible inclusions that may detract from the beauty of the diamonds.
Certification
Before buying a diamond, always ask to study its certificate as confirmation that it has been professionally examined and certified. A diamond certificate (also known as a grading report, quality document or dossier) is a report produced as a result of a careful examination by a team of gemmologists. The diamond is scrutinized, measured and evaluated using precision tools of the industry is order to create a detailed analysis of its colour, clarity, polish symmetry and dimensions. A cut grade may also be included in the case of round diamonds.
A certificate enables you, the purchaser to know that the diamond you intend to buy has been evaluated by an unbiased team of professionals so that you can buy with confidence.
Always ensure that the diamond certificate is a genuine and authentic document from one of the following institutes:
- GIA (Gemmological Institute of America)
- AGS (American Gemmological Society)
- HRD (Antwerp World Diamond Centre)
- IGI (International Gemmological Institute)
- EGL (European Gemmological Laboratory)
Care
A diamond is the hardest substance known to man and as such, is extremely resistant to damage either by heat of from scratching. It would take an extremely hard blow to chip a diamond and obviously under normal conditions of everyday use, this would be very unlikely to occur. However, normal exposure to every day substances, house hold chemicals, toiletries etc. can create a film over the diamond’s surface which in turn will dull its performance. We recommend regular cleaning to maintain your diamonds sparkle and brilliance.
Cleaning Method
For home cleaning, gently scrub your diamond with a soft brush using a solution of one part ammonia to six parts water, taking care not to damage the setting. Rinse with clean water. We recommend having your diamond cleaned professionally once a year and having the setting checked.
Storage
It is always advisable to store your diamond jewellery separately and individually as diamonds, because of their hardness may well scratch and dull other jewellery.
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