Purchasing a diamond does not have to be an overwhelming experience. The characteristics of a diamond, also known as the Four C’s (Cut, Clarity, Colour and Carat Weight), all contribute to the price and appearance of the stone. Understanding a diamond’s characteristics will help you determine your best possible diamond choice, while remaining within your budget.
In choosing a diamond, one can place a priority on the appearance of the diamond, or the overall carat weight. When selecting a diamond based on the appearance, select your cut, clarity and colour grades, and then you will be able to determine the carat weight that will fit into your budget. If the diamond size is your priority, you may have to adjust the cut, colour or clarity to accommodate your budget.
THE FOUR C’S:
The cut grade is a measure of a diamond’s sparkle or ‘light performance’. It refers to the proportions and finish of a polished diamond and it has the greatest overall influence on a diamond’s beauty. Most diamonds start as an octahedron rough, an eight sided natural crystal that resembles two pyramids joined together. When a diamond is proportionally cut to exact or ideal specifications, light is reflected from the top of the diamond, providing the maximum brilliance, rather than leaking out of the bottom if it is cut too shallow or too deep.
A diamond’s cut is also measured by finish, brightness, fire and scintillation. Finish refers to the quality of polish and the symmetry of the diamond and all its facets. Brightness (or brilliance) is the effect of the internal and external reflection of white light. The proportions of the diamond play the main role in determining the brightness. Fire represents to the flashes of colour resulting from white light being dispersed into spectral colours throughout the stone, and scintillation refers to the areas of light and dark when viewing the top of the diamond.
Until the 19th century, diamonds were very rare and cut for maximum weight retention from the original rough shape. Old mine cut diamonds were chunky with a square outline and small table and culet (top and bottom facets) reflecting the crystal shape that they were cut from. By the early 20th century, cutters realized that diamonds were more beautiful and displayed more fire and brilliance when the proportions and angles between facets were of certain dimensions. Many of the diamonds found in antique or estate jewellery are pre 19th century and therefore exhibit older cuts.
CUT GRADES FOR MODERN DIAMOND CUTS:
- Ideal/Excellent Cut: Reflects nearly all light that enters the diamond. Represents approximately 3 % of diamond quality based on cut. Is brilliant and rare.
- Very Good Cut: Reflects nearly as much light as an Ideal Cut and represents approximately 15% of diamond quality based on cut.
- Good Cut: Reflects most of the light that enters. Represents approximately 25% of diamond quality based on cut.
- Fair Cut: Is less brilliant than a good cut but, is still a quality diamond. Represents approximately 35% of diamond quality based on cut.
- Poor Cut: Reflects most of the light that enters either through the bottom or through the sides and will be less brilliant than the majority of diamonds.
- European Cut: Has 58 facets, as does the modern round brilliant cut but, the round brilliant is technically more precise than its European predecessor. The European cut, however has a smaller table (flat top portion of the diamond) and larger crown area (the angled top area of the diamond) so that it breaks up the light and acts like a prism so that the diamond can scintillate with the fire of spectral colours when rotated. The round brilliant, conversely, has a larger table area and allows for more light to be returned to the eye without interference. This is referred to as brilliance.
Clarity refers to the purity of a diamond and the natural imperfections that occur within almost all diamonds. Diamonds are formed deep within the earth’s crust and are subject to tremendous heat and pressure which cause internal blemishes. Most often these imperfections are referred to as inclusions and those diamonds with the least number or smallest imperfections are considered to be higher grade. The size, nature and location of the imperfection will also help to determine the clarity grade assigned to an individual stone. For example, if the inclusion is situated off to the side of the diamond, it may not be as disruptive or apparent as an inclusion that is situated in the middle of the stone. Many inclusions tend to be microscopic and can only been seen with a microscope or 10x jeweller’s loupe. The term to describe these diamond’s is “eye clean” – a diamond that has no imperfections visible to the naked or unaided eye. These diamonds generally don’t affect a diamonds beauty in any palpable way. Those inclusions that are apparent to the unaided eye are considered less desirable and are therefore, less expensive.
The following chart will help to explain the terms assigned to the varying levels of clarity:
- FL – Flawless: Free from internal inclusions and external flaws. They are extremely rare and command higher prices.
- IF – Internally Flawless: No internal imperfections. Extremely rare and command higher prices.
- VVS1, VVS2 – Very Very Slightly Included: Very difficult to see imperfections under 10x magnification. Considered excellent clarity diamonds and are.
- VS1, VS2 – Very Slightly Included: Used for diamonds that have very small internal and external characteristics that are difficult to locate with 10x magnification and a skilled observer. Considered good clarity diamonds but, are less expensive than VVS Clarity Diamonds.
- SI1, SI2 – Slightly Included: Imperfections are visible under 10x magnification but usually not visible to the naked eye. Can represent a good diamond value.
- I1, I2, I3 – Included: Imperfections are visible to the naked eye.
Although diamonds occur in all colours of the rainbow, most diamonds range from colourless to light yellow or brown. Diamond colour grades are determined by lack of colour. The top color is D which is colourless. D, E and F are colourless to the human eye; G, H, I and J are near colourless; K,L and M are faint yellow, and the alphabet continues through to Z. Once diamonds have reached a certain intensity of colour, they can be considered fancy, as in a Canary Yellow Diamond.
Carat Weight refers to a diamond’s weight, but does not necessarily reflect the diamonds size. Both the size of the table (top of the diamond) and the diamond’s cut must be evaluated in order to correctly determine the diamond size. For example, a better cut diamond may appear larger because it has a better return of light, but a poorly cut diamond may appear smaller because it may hide girth at the base of the diamond (or culet) where it is not as evident. Therefore, it is possible to have a diamond of a lower carat weight, but higher cut grade that appears larger than a diamond with a larger carat weight, but poor cut.
The diamond weight is measured in terms of points and carats. One carat is the equivalent of 1/5th of a gram. Further, a 1-carat diamond is equivalent to 100 points. Therefore, a ½-carat is .50 points, a ¼- carat is .25 points, and so on. Substantially more small diamonds are mined than large diamonds resulting in the higher price per carat for successively larger diamonds due to their inherent rarity. Diamond prices jump at half and full carat weights. For example, a .99 carat diamond will be priced at significantly less than a diamond that is 1.00 carat, and there will be no detectable difference to the eye.
When deciding upon what carat weight diamond to purchase, you should consider the size of the hand and finger (the smaller the finger, the larger the diamond will appear), the style of setting and, of course, your budget. If the carat weight is most important to you and you are attempting to stay within a particular budget, you may decide to lower your expectations in terms of cut, clarity or colour. An average quality and very acceptable diamond would be one with good cut, SI clarity and J colour.