Understanding Diamond Cut
In the GIA diamond grading scale, ‘cut’ refers to the quality of a diamond’s cut, specifically its proportions and symmetry. It is important to note that the cut of a diamond does not refer to a diamond’s shape (Pear Shape, Heart Shape, Round Shape, etc.). The cut quality of a diamond directly affects its overall look. It also determines a diamond’s ability to capture and reflect light, thereby producing brilliance. In fact, many consider cut to be the most important factor when choosing a diamond.
Diamond Cut Grades
Since the establishment of standardized diamond grading criteria, diamond cut quality is now described as the following cut grades:
Excellent Diamond Cuts are the most ideal. They have the maximum measure of brilliance for it reflects the most light and radiates the best sparkle.
Very Good Diamond Cuts are very similar to diamonds of Excellent Cuts. They also offer outstanding brilliance with the majority of light reflecting through the diamond.
Good Diamond Cuts provides brilliance at a more cost-effective price point.
Fair Diamond Cuts offers a little amount of reflection and brilliance.
Poor Diamond Cuts allows light to escape, providing little to no brilliance and sparkle.
Elements Affecting the Cut Quality
The GIA (Gemological Institute of America) has developed a diamond cut grade system that can be broken into seven components:
- Weight ratio – The appearance of the size of a diamond relative to its weight
- Durability – The possibility of chipping or breaking due to an excessively thin girdle
- Polish – How smooth or scratched the surface is after the polishing process
- Symmetry – How well balanced and aligned the facets are
- Brightness – Brightness created from white light reflecting from the surface and inside of the diamond
- Fire – The dispersion of light into colors of the visible spectrum
- Scintillation – Flashes of light produced when a diamond is moved in the light
Diamond cutting requires a high level of craftsmanship and must strike the right balance between stone size and cut quality.
Does Cut Grade Influence the Price?
The cut of a diamond impacts its overall appearance and brilliance, and the greatest amount of brilliance can only be found in a diamond that has been exceptionally cut. In its rough state, a diamond can look dull in appearance. There are also additional costs for skilled labor required to craft an ideal cut diamond. So yes, a diamond’s cut is definitely an important feature that impacts a diamond’s appearance, along with its price.
In all cases, a diamond that is cut well will appear bigger and more radiant in comparison to a diamond that is cut poorly, and for obvious reasons, people would prefer to have a well-cut diamond. However, there are still some that would buy poorly cut diamonds to match their budget. For people who are looking for something a little more cost-effective, we would advise purchasing a diamond that is lower in color grades rather than cut quality because as mentioned before, having a good quality cut will make your diamond appear more attractive and radiant.
However, your final buying decision should still be based on you or your partner’s personal preference.
ICONIC offers two different diamond cut grades: Excellent and Very Good. If you require any further information or would like to request a specific cut grade or shape, please feel free to contact us.
When people are asked to describe a diamond shape, most will reply “round” and indeed this is regarded as a classic design, particularly popular with engagement rings. Although strictly speaking a round diamond could be almost any cut, the most famous and prominent is the round brilliant diamond cut. The brilliant-cut is noted for featuring either 57 or 58 facets which give the diamond its famous sparkle. The round brilliant cut is what some would say cut diamonds should look like.
A relatively recent creation, the modern princess-cut features distinctive pointed corners. Traditionally square, some princess-cut diamonds are slightly rectangular in shape, though this may be difficult for the untrained eye to detect. The princess cut is one of the most popular cuts and can have up to 76 small facets. The classic prong is the best setting for princess cut as it allows more light to pass through the stone and uses less metal than other settings. Princess cut diamonds typically cost less per carat compared to round diamonds.
Widely popular in the late 19th century, antique-style cushion-cut diamonds have recently experienced a resurgence in popularity. Influenced by the old mine cut, which featured rounded corners and large facets, the cushion cut diamonds have a soft, romantic appearance. Ranging from square to rectangular, height to length ratio is an important factor when considering a cushion-cut diamond. Clarity is also important with this cut, as the larger facets highlight the diamond’s clarity.
The modern asscher cut can be described as a square emerald cut; both have a pavilion cut with rectangular facets. Asscher-cut diamonds feature step facets and cropped corners that make them appear octagonal when viewed from above and offering brilliance along with its signature appeal. Designed to emphasize clarity, the asscher cut allows you to see all the way through the diamond. There are two types of Asscher Cuts. There’s the standard Asscher Cut diamond and there’s the Royal Asscher Cut. Both were created by the Royal Asscher company. Asscher diamonds usually have 58 facets, the same as a round brilliant. The arrangement of these facets gives it a vintage “hall of mirrors” look.
Originally developed for the cutting of emeralds, the emerald cut is prized for its clean lines rather than its brilliance. A large table and the step cuts on the pavilion give emerald-cut diamonds a unique look that really accentuates clarity. Similar to oval diamonds, the length to width ratio of emerald-cut diamonds can vary. A length-to-width ratio of 1.40-1.50 ratio is ideal for a classic emerald-cut shape usually consists of 57 facets. Emerald cut diamond shapes go well with solitaire and simple pave settings and are perfect for three-stone settings.
With curved edges and two pointed ends, the unusual marquise-cut is a modified brilliant cut. With its long, narrow boat-shape, marquise cuts have the largest crown surface area of any diamond shape, giving the illusion of a larger stone. The shape of marquise diamonds is also ideal for elongating the fingers of the wearer.
An oval-cut diamond combines the brilliant faceting of round diamonds with an elegant elongated shape. Oval diamond cuts actually give diamonds the appearance of being larger than they actually are. It can also make the wearer’s fingers appear longer and slimmer. Traditional oval diamonds have a length to width ratio between 1.35 and 1.50.
Like the emerald-cut, a radiant-cut diamond has straight sides and trimmed corners. However, their faceting gives them a much greater level of brilliance, resulting in a very sparkly diamond. Radiant cut diamonds use a hybrid cutting style that combines the clean lines of square cuts with the faceting of the round brilliant cut. The shape of radiant-cut diamonds can range from square to rectangular. Radiant cut diamonds are one of the most affordable cuts because the cutting process uses a larger percentage of the original diamond rough, so very little goes to waste.
Featuring a single tapered point, the pear cut diamond is reminiscent of a water droplet. Worn with the tip pointing either up or down the finger, the elongated pear-shape subtly slims the fingers. This is a vintage style diamond cut and is known for high sparkle. The dimensions of pear-shaped diamonds vary, though the most traditional ratio is between 1.45 and 1.75. Pear shape diamonds are versatile as they can be perfect as a center stone or used as lovely diamond accents.
A heart-shaped diamond is both a symbolic and unique choice for an engagement ring. A modified round brilliant cut, heart shaped diamonds are generally worn as solitaire rings or pendants and are made up of between 56 to 58 facets giving this stone high brilliance.
How cuts affect light refraction:
Though we already touched on the topic of cut styles and shapes, we have yet to talk about cuts in terms of quality. This relates more to the proportions of the cut and the skill of the diamond cutter behind it. The width and depth of the stone affect the way light is reflected, which in turn would affect its brilliance and optical appeal.
When the diamond is cut in such a way that the pavilion depth is far too large, it is considered a deep cut. This means that the light won’t reflect back (upwards), stealing away from the diamond’s shine, quality and price.
A shallow cut is seen when the pavilion depth is cut far too small in proportion to the diamond width. This, same as the deep cut, causes poor light reflection and affects the jewel’s price, quality and brilliance
The fine cut is one of two commonly acceptable cuts. Its proportions are close enough to the ideal cut that it displays brilliance and light reflection that might look perfect to the naked eye. The girdle size is a common difference between the fine and ideal cuts, as well as the crown size, at least in proportion to the rest of the diamond.
An ideal cut is when a diamond has perfect proportions and light reflection. Diamonds of an ideal cut have the most shine and brilliance, with light reflected directly back at the viewer’s eyes. This is the cut to go for every time.