Shopping for quality diamonds starts with the 3Cs, not the 4Cs. Surprisingly? Cut, clarity and colour, not carat weight, determine a diamond’s quality. After all, size doesn’t affect quality. Learn how to buy a beautiful diamond based on the 3Cs, fluorescence and shape.
What factors affect diamond quality?
The beauty of diamonds comes from the combination of nature and man. Nature creates rough diamonds with different inclusions and different colors. And the cutting of rough diamonds by humans determines the priority of the 4Cs (cut, color, clarity and carat weight). Should the cutter cut away most of the inclusions to get a high-clarity diamond, or should he try to preserve the size of the diamond? It seems that the quality of a diamond depends not only on the raw material, but also on the way the cutter chooses to cut the diamond. In the 4Cs, only cut, color and clarity determine the quality of a diamond. Carat weight does not affect the quality of a diamond, and a small diamond can be as well-crafted and beautiful as a large diamond. In the 4Cs, the only thing that humans can fully control for untreated natural diamonds is the cut, because the cut depends on the quality of the craftsmanship.
What is the shape quality of a diamond?
Judging the shape quality of a round brilliant diamond is pretty straightforward. Round brilliants are, of course, just that — round! Most round brilliants, especially those with an Excellent or Very Good cut grade, are perfectly round, or at least so round that nothing can be seen to deviate from the shape to the naked eye.
Judging the shape quality of a fancy cut diamond is much more complicated. Fancy cut diamonds come in a variety of shapes and cutting styles, each with its own length-to-width ratio and standards, so GIA does not grade the cut of fancy cut diamonds. In addition, personal preference is an important factor in judging. There are four things to pay attention to when judging a fancy shape:
Length-to-width ratio: The length-to-width ratio represents the relationship between the length of a fancy-shaped diamond and its width, with the width represented by the number 1. Most people find that they work better when cut to a certain ratio. For example, the most popular ratios for emerald cuts, rectangular cushion cuts, and pear cuts are between 1.50:1 and 1.75:1. Another reason it’s important to consider the length-to-width ratio is that diamonds that are too long or too narrow can be easily damaged.
Axial Symmetry: For heart and pear shaped diamonds, if a line is drawn through the middle, the outline of the diamond should be the same on both sides. For oval, square, rectangular and marquise cut diamonds, the outline should be the same vertically and horizontally. Symmetry is an important factor in ensuring the diamond’s clear and even appearance, which plays an important role in maximizing the diamond’s brilliance. The GIA grading report for fancy cut diamonds does not include the diamond’s cut grade, but does state the diamond’s symmetry and polish grade .
Smooth curves: Curved diamonds such as heart, pear and oval shapes should have full, rounded “lobes” or “shoulders.” Their curves should be smooth and free of harsh, unsightly flat spots.
Clarity of Shape: The shape of a diamond should be sharp and clear. For example, a heart-shaped diamond should have a sharp opening and a distinct point, rather than being flat like a pear. Sometimes the appeal of a diamond’s shape comes down to its proportions. If an oval diamond’s length-to-width ratio is too small, it may look like an uneven round diamond.
What is the cut quality of a diamond?
Cut quality refers to the combined effect of a diamond’s proportions, design and finish on its beauty. Diamond proportions relate to the angles and relative sizes of a diamond’s facets. Diamond design refers to a diamond’s weight ratio (how heavy or light it is relative to its diameter) and durability (the risk of damage to delicate, thin areas). Diamond finish includes two major factors – polish (the quality and evenness of the faceted surfaces) and symmetry (the arrangement and placement of the facets). Together, these factors reflect the quality of the craftsmanship of a diamond’s cut. Cut quality is important because it affects how a diamond interacts with light, which determines its brightness, fire and scintillation.
What are brightness, fire and scintillation? Why are they important?
In simple terms, brightness is the amount of white light reflected from a diamond’s facets to an observer’s eye. Fire is the flashes of color seen by an observer as the diamond disperses white light into a spectrum of colors. Scintillation is the flickering and patterning of light and dark areas seen by an observer as the observer or the diamond moves.
These three factors are important in making a diamond appear to have beautiful light and shadow effects.
GIA grades the cut of round brilliant diamonds, but not fancy cut diamonds. Whether your diamond’s cut is graded or not, you can check its cut quality using the following methods:
- Check the diamond’s brightness and sparkle under diffuse (white) light. Does the diamond reflect a lot of white light (brilliance)? Does it flicker when you turn it (sparkle)? Are the light and dark areas evenly distributed (pattern)? If so, your diamond is well cut.
- Check the diamond’s fire under incandescent light. Does the diamond sparkle with a lot of fire? A diamond should have fire in as many colors of the rainbow as possible.
- Look at your diamond under a variety of lighting conditions. From diffuse to spot lighting, different lighting environments can drastically change the appearance of your diamond. How does your diamond look in a restaurant, outdoors, and in the office? If your diamond looks great under a variety of lighting, then there’s a good chance you’ve purchased a very good diamond!
What is the color quality of a diamond?
With the exception of very rare fancy white diamonds, when most people refer to a “white” diamond they are actually referring to a colorless diamond. Furthermore, most colorless diamonds are not truly colorless, but have some degree of yellow, gray, or brown. Therefore, GIA created the D-to-Z color grading system to help people determine the degree of color in a diamond.
Generally speaking, the less color a diamond has, the more people like it. Only diamonds with a color grade of D are completely colorless. But most people can’t tell that a diamond with a color grade of G has color unless it is placed next to diamonds with a higher color grade. In addition to color grade, the following two factors also affect diamond color:
Cut: Brilliant cuts, especially round brilliants, will show less color in a diamond, in part because they have more facets. All white light is reflected from within the diamond and then back to the viewer, making the diamond appear brighter. Step cuts, such as the emerald and Asscher cuts, have fewer facets over larger areas, which means less brilliance. Step cuts are not about brilliance, but about creating an elegant, shimmering hall of mirrors effect. The corners of pear, heart, and marquise diamonds have more color concentrated in them, making them appear darker. If you are buying a step cut diamond or one with one or two sharp corners, it is best to choose a higher color grade.
Setting: If you want a yellow or rose gold ring, you can save money by purchasing diamonds that are graded G or lower. DF color diamonds set in yellow or rose gold can make the diamond appear warmer. If you are planning to buy a white gold or platinum ring, then consider diamonds that are graded GH or higher. Setting diamonds that are graded I or lower in white gold or platinum will make the diamond appear warmer because these metals will contrast with the color of the diamond and make the color of the diamond more obvious. Conversely, setting warm-toned diamonds in yellow or rose gold can mask the color of the diamond.
What is the clarity quality of a diamond?
Most diamonds have inclusions visible at 10x magnification. These inclusions, which are crystals or irregularities trapped within the diamond, are a result of the diamond’s formation process. These inclusions, or clarity features, help determine if a diamond is natural, and also allow scientists to learn a lot about the Earth. However, most consumers want their diamonds to be as clear as possible. So GIA created the diamond clarity grading system , which ranges from “Flawless,” “Internally Flawless,” all the way to “Included.” But even a “Flawless” diamond may not be flawless. “Flawless” simply means that no inclusions or blemishes are visible on the diamond when it is magnified 10x.
In most diamonds with a clarity grade of VS2 or SI1, inclusions are not easily visible to the naked eye. Diamonds with a clarity grade of SI2 or I (Included) are more likely to have inclusions. Of course, this also depends on the observer’s vision. But in general, budget-conscious consumers can save money by choosing diamonds with a clarity grade of VS or SI; diamonds of this clarity may have similar clarity performance to diamonds with higher clarity grades under naked eye conditions. However, if you or the recipient of the diamond is a perfectionist, then perhaps a diamond with a clarity grade of VVS2 or higher is more suitable for you, but this also means that you will have to pay a higher price.
When determining diamond clarity, you need to pay attention to the following points:
No inclusions visible to the naked eye. If you can’t see any inclusions without magnification, or only a few hard-to-find inclusions, then the diamond is likely clear enough for your jewelry needs.
The location, size and visibility of visible inclusions. Inclusions that are farther from the center of the diamond are less noticeable. They are even less noticeable if they are near the edge, corners or bevels of a brilliant cut diamond (round, marquise, pear, princess, etc.). Brilliant cut diamonds have many facets on their corners and bevels, so tiny inclusions are often not noticed. Inclusions near the edge may even be hidden by the jewelry setting. Obviously, smaller, lighter colored inclusions are harder to see and will have less impact on the diamond’s appearance.
Cutting style. Round brilliant cut diamonds have more facets, so inclusions are usually less visible. More facets allow light to bounce around more easily, creating intricate patterns that can hide smaller inclusions. Step cut diamonds have larger facets and fewer facets, which creates a less complex pattern and makes inclusions more noticeable. If you’re going to choose a diamond with a lower clarity grade, consider buying a brilliant cut diamond.
Durability. This is an important consideration for diamonds with lower clarity grades. Diamonds in the I clarity range, especially those with I2 or I3 clarity grades, can sometimes have durability issues. It’s important to make sure your diamond doesn’t have large chips or breaks (feathers) in the girdle or corners, as these can make the diamond more susceptible to damage. If a diamond has a feather, it’s best if it’s inside the stone and not touching the surface.
What is Diamond Fluorescence?
Fluorescence is the visible glow (luster) that some diamonds exhibit when exposed to ultraviolet light. About a third of diamonds have visible fluorescence. These diamonds are sometimes priced lower, making them a good buy. Here are some things to consider when shopping for a diamond with fluorescence:
The color grade of a diamond. Strong fluorescence can reduce the value of a top color diamond (DF). In rare cases, very strong fluorescence can make a diamond appear milky or hazy. In addition, blue fluorescence can increase the value of diamonds with lower color grades (I and below) because it reduces the yellow hue in such diamonds.
Fluorescence color. More than 95% of fluorescent diamonds fluoresce blue. Other colors of fluorescence include yellow, red, green and white. Blue fluorescence helps mask a diamond’s warm tones, while yellow or green fluorescence can make a diamond appear warmer or more vibrant. As a result, diamonds with yellow or green fluorescence tend to cost less than diamonds with blue fluorescence.
Fluorescence Strength. If a diamond has weak to moderate fluorescence, you probably won’t notice it in most lighting conditions. If a diamond has strong to extremely strong fluorescence, it may appear milky in sunlight (with UV light). The intensity of a diamond’s fluorescence will be noted on the GIA grading report. However, the easiest way to see what fluorescence in a diamond looks like is to view the diamond in person under different lighting conditions.
The grading results on your GIA grading report show how your diamond performs in terms of color and clarity (and cut for round brilliant cut diamonds). Ultimately, however, you should choose the diamond that you think looks the best (after comparing it to many other diamonds, of course). To fully understand the above tips, read or watch the video on how to interpret a GIA grading report.
