As of 2023, Botswana is the world’s largest producer of diamonds by value and second largest producer of diamonds by volume. Some of the world’s largest diamonds have been found here. Diamonds help build Botswana’s infrastructure, including schools and hospitals, support female leadership, and combat diseases such as AIDS.
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Some consumers turn to Canadian diamonds in their quest for sustainable natural diamonds. Learn about their discovery, how diamonds help Canadian communities and how a GIA Diamond Origin Report lets you know if your diamond is a Canadian diamond.
Diamonds are valuable purchases, but you can save money on buying one by understanding the 4Cs and other value factors. Learn how to choose a diamond that is beautiful and still within your budget with the tips below.
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A VVS diamond (Very Very Slightly included) and a VS diamond (Very Slightly included) differ in clarity and, if all else is equal, they can differ significantly in price. Knowing these differences can help you make a smart engagement ring purchase.
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Courtesy: Chip Clark, Smithsonian Institution
Diamond fluorescence is a fascinating phenomenon where diamonds glow when exposed to long-wave UV rays. It can sometimes increase or decrease the value of a diamond. It can also affect diamond appearance—or not. How should you take fluorescence into account when choosing the perfect diamond? In this article, we’ll cover:
Fluorescence is the glow you sometimes see when an object emits visible light. Some diamonds fluoresce when they are exposed to long-wave ultraviolet (UV) rays from sources like the sun. This can cause them to emit a bluish light or more rarely, a yellow or orangy light. Once the UV light source is removed, the diamond stops fluorescing.
No. Only about 25% to 35% of diamonds exhibit some degree of fluorescence in reaction to long-wave UV light. More than 95% of these diamonds fluoresce blue. A rare few fluoresce other colors such as yellow or green.
Fluorescence is not a grading factor like the GIA 4Cs (color, clarity, cut, and carat weight), but it is an identifying characteristic. GIA Diamond Grading Reports and Diamond Dossiers describe a diamond’s fluorescence by its intensity under long-wave UV light (None, Faint, Medium, Strong and Very Strong). If the fluorescence is Medium, Strong, or Very Strong, the color of the fluorescence will be noted.
Photo: (Top) Maha Tannous/ GIA, (Bottom) Harold & Erica Van Pelt
Some trade professionals think blue fluorescence enhances a diamond’s appearance, especially in diamonds with I to M color grades. Bluish fluorescence can make a faint yellowish diamond appear more colorless in UV light, which is part of natural daylight. As a result, diamonds with color grades I to N with a very strong to medium bluish fluorescence may have a slightly higher per-carat price than diamonds with similar color grades that do not fluoresce.
The opposite is true for diamonds with higher color grades. In the trade, diamonds in the D to H color range with bluish fluorescence are often considered less desirable than similar grade diamonds without fluorescence, because some people believe that bluish fluorescence may cause diamonds to have a hazy or oily appearance. In a recent study, GIA observed that blue fluorescence has little to no impact on transparency except in extremely rare cases where a diamond (such as the Portuguese diamond) has a light-scattering defect. These defects cause haziness that can sometimes be intensified by strong fluorescence, thus reducing the contrast in the face-up pattern of the diamond. Fluorescence does not cause haziness by itself, however. Also, this “overblue” hazy effect occurs in fewer than 0.2% of the fluorescent diamonds submitted to GIA.
Nonetheless, the association between fluorescence and haziness persists, and diamonds in the D to H range with very strong fluorescence often sell for less than diamonds that do not have fluorescence, even though their color and transparency are most likely unaffected by their fluorescence. These diamonds may prove to be a good deal. If you’re not familiar with the GIA Color Scale, learn more with the GIA Diamond Color Chart.
No, fluorescence does not cause haziness in diamonds. Fluorescence can increase the pre-existing haziness of a diamond caused by light-scattering defects, thus reducing the contrast in its face-up pattern, but it does not cause haziness in and of itself. As light-scattering defects are incredibly rare, most consumers don’t need to worry about fluorescence impacting a diamond’s appearance in most lighting situations, even if the diamond has Strong to Very Strong fluorescence. But this does mean that consumers should look at a diamond in person. Any haziness intensified by fluorescence, if present, will be noticeable in (for example) daylight-equivalent lighting.
The center diamond is an H color diamond with Strong to Very Strong fluorescence. The two diamonds flanking it on either side are H color diamonds with no fluorescence. There is no visible difference in color or transparency. Courtesy: Jian Xin (Jae) Liao
In order to study the effect of blue fluorescence on diamond appearance, GIA scientists assembled sets of E, G, I, and K color-grade diamonds. The diamonds in each set were as similar as possible except for the intensity of their blue fluorescence. Diamond graders, trained professionals, and average observers viewed the diamonds in controlled conditions to make a judgment about their appearance. It seems that, for the average observer, meant to represent the jewelry-buying public, no systematic effects of fluorescence were detected. In general, viewers perceived that strongly blue fluorescent diamonds had a better color appearance when viewed table-up. Most observers saw no relationship between fluorescence and transparency.
Seen here are seven diamonds seen under daylight-equivalent illumination versus long-wave UV illumination. Photo: Kevin Schumacher/GIA
Diamond fluorescence is neither good nor bad. Some people find fluorescent diamonds beautiful and fascinating—others may not. Opinions range across the spectrum.
If you are considering a diamond with bluish fluorescence, look at it under different kinds of lighting, including natural daylight and compare it to other diamonds of the same color grade, and see if you notice any difference. If you do notice a difference, see if you like it!
This beautiful brooch contains several diamonds that fluoresce under long-wave UV illumination.
Now that you know more about diamond fluorescence, read on to learn how light affects a diamond’s appearance.
Buying a quality diamond begins with 3Cs—not 4. Surprising? Cut, clarity and color all determine diamond quality, but carat doesn’t. After all, size doesn’t affect quality. Learn how to buy a stunning diamond based on 3Cs, fluorescence and shape.
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If you’re shopping for a diamond engagement ring and see the price tag, you may wonder, are diamonds rare? Why do they cost so much? Is demand only driven by advertising? Do they have intrinsic value? We look at these questions and more.
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If you’re shopping for an engagement ring, you need to know about carat weight – the measurement of how much a diamond weighs. Carat weight is important because it helps determine a diamond’s price and reflects its rarity. We take a closer look. (more…)
A GIA diamond cut grade is key to knowing how well your round brilliant diamond will sparkle. Cut is the most complex of a diamond’s 4Cs. Let’s cover some essentials so you can pick the perfect round brilliant diamond engagement ring.
In this blog, we cover:
The most popular diamond in the marketplace is the round brilliant. Experts estimate that this cut alone accounts for more than 70% of all diamonds sold today. The quality of a round brilliant diamond’s cut determines how much the diamond sparkles. To pick a diamond whose flashes of light enchant the eye, you need to know the 4Cs of diamond quality, the universal standard for judging diamonds: color, cut, clarity and carat weight. All else being equal, the better the cut grade, the more valuable the diamond.
Some professionals consider cut the most important C of diamond quality. A well-cut round brilliant delivers that unmistakable, stop-in-your-tracks light show that telegraphs “diamond” across a crowded room. If the diamond is well cut, most compromises in clarity, color and even carat weight can be forgiven. A diamond’s cut grade is also an indication of how well it was designed and crafted. So, understanding the diamond cut grade is key to picking a round brilliant that’s not only beautiful, but also the best value.
In arriving at its cut grading system, GIA spent 15 years studying how light behaves within a round brilliant cut diamond. GIA’s aim was to understand the factors that contribute to a round brilliant’s appearance and to determine which of those factors – or combination of factors – produce diamonds that people consider attractive.
GIA’s research included the use of advanced computer modeling to analyze tens of thousands of possible proportion combinations. GIA then validated its research with human subjects, conducting more than 70,000 observations on actual diamonds, to determine which diamonds people found appealing and why.
The result was the GIA Cut Grading System, which evaluates the cut quality of a round brilliant diamond along a five-point scale ranging from Excellent to Poor.
A GIA cut grade evaluates:
The GIA diamond cut grade is based on seven factors: brightness, fire, scintillation, weight ratio, durability, polish and symmetry.
This 2.02 carat (ct) round brilliant has excellent cut, polish and symmetry. Courtesy: 1stdibs.com
The reason behind the sparkle of this 1.01 ct round brilliant cut diamond engagement ring is the quality of the diamond’s cut. The diamond received an Excellent cut grade from GIA. Courtesy: 1stdibs.com
A key component of a GIA diamond cut grade is the diamond’s face-up appearance – or how the diamond looks when viewed from above, as if it was set in an engagement ring. People love diamonds for their dazzling interplay with light – which the layperson often translates as “sparkle.” But there’s a lot more going on here.
When you see internal and external white light reflected from a diamond, you’re noticing “brightness.” If you see the scattering of light into all the colors of the rainbow, you’re being treated to “fire.” Sparkle is actually “scintillation,” the pattern of bright and dark areas caused by reflections within the diamond as it or the light source moves. What you might consider “sparkle” is really the overall visual effect of these three factors. A GIA cut grade includes an assessment of how well a diamond delivers on each of these attributes.
This round brilliant cut diamond shows good brightness and fire. Scintillation, the pattern of light and dark areas and the flashes of light, or sparkle, can only be seen when a diamond is moved. Copyright: GIA & Harold and Erica Van Pelt
A diamond’s proportions – its crown and pavilion angles and the relative measurements of its facets – are key contributors to a diamond’s overall face-up appearance. Remember that facets are tiny mirrors. Their size and placement will influence how light behaves as it passes through the diamond and back to your eye.
A diamond’s proportions can help predict how well a diamond will deliver brightness, fire and scintillation. However, an important outcome of GIA’s cut research was the finding that there is no single set of proportions that defines a well-cut round brilliant diamond. In fact, diamonds with different proportions can receive the same cut grade. The diamonds may look and perform differently but they will still have a similar impact on the observer. So, as a diamond shopper, you need to look beyond the measurements on a grading report. Be sure to view a diamond in person to see if it’s the right choice for you.
This graphic illustrates the proportions that affect a diamond’s cut grade. The crown and pavilion angles and the relative measurements of its facets contribute to a diamond’s brightness, fire and scintillation.
While face-up appearance is all about how a diamond looks, design and craftsmanship evaluate the quality of the diamond’s manufacture. Poor design could add unnecessary weight to a diamond or cause durability issues that would prevent you from enjoying it for a lifetime. A diamond with poor craftsmanship won’t deliver much in the way of brightness, fire and scintillation. In evaluating these two components, the GIA Cut Grading System takes into account the diamond’s physical shape, its proportions, its weight ratio, and the care that went into fashioning and polishing its facets.
Design
Design refers to decisions made during the fashioning process that determine the diamond’s physical shape, as seen in its proportions, weight ratio and durability. Weight ratio is the diamond’s weight in relation to its average girdle diameter (a fairly complex mathematical equation). A diamond with a smaller girdle diameter relative to its weight might appear smaller face-up than its well-designed counterpart, because much of the weight would be “hidden” in the overall depth of the diamond. For example, while a diamond with a thicker girdle could look great, the girdle is hiding unnecessary weight. As a result, you might end up paying more for a heavier diamond with no greater visual impact for the added cost. The bottom line: A diamond should not weigh more than its face-up size would indicate.
These pictures show the importance of weight ratio. Both of these diamonds have the same average girdle diameters, so face-up they appear to be the same size. But the diamond on the right has a much thicker girdle, so it weighs more (0.71 ct vs. 0.61 ct). The thicker girdle has no visual benefit, but the added weight will make the diamond more expensive. Photos: Maha Tannous/GIA
Durability in the case of a round brilliant diamond refers to the risk of damage that might result from an extremely thin girdle. Such a girdle can make a diamond highly vulnerable to damage during the jewelry setting procedure or even normal wear. Considering how much a diamond costs and its emotional significance, you want to avoid one that is susceptible to damage. A GIA Diamond Grading Report can eliminate this concern.
Here is an example of why durability is important. This 1.35 ct diamond has girdle areas that are very thin to extremely thin, making it more susceptible to damage during everyday wear. Courtesy: Gary Roskin, G.G., F.G.A.
Craftsmanship
Craftsmanship describes the care that went into fashioning the diamond, as seen in its polish and symmetry. Polish refers to the overall quality and condition of the facet surfaces. It includes evaluation of any blemishes created by the polishing process or during wear. Polish is critical to the mirror-like performance of a diamond’s facets.
The diamond on the left shows lines created during the polishing process. The diamond on the right has abraded facet junctions caused by wear. Polish lines and abraded facet junctions can also affect a diamond’s clarity grade. Photos: Mitchell Moore/GIA
Symmetry is the exactness of a finished diamond’s shape and the arrangement and placement of its facets. A symmetrical diamond has an even display of brightness, fire and scintillation. A diamond with poor symmetry will have poor light performance, meaning that it’s likely to look flat.
All eight sections of a round brilliant cut diamond should be identical. This symmetry will help produce even brightness, fire and scintillation. Illustration: GIA
GIA evaluates a round brilliant diamond’s cut based on seven components – brightness, fire, scintillation, weight ratio, durability, polish and symmetry – to arrive at a GIA diamond cut grade, which ranges from Excellent to Poor. The grade is set by the lowest assessment the diamond receives for five of the seven components. In other words, if a diamond receives a Poor grade for brightness, then the highest its overall cut grade can be is Poor. The exceptions are polish and symmetry, which are assessed using standard GIA grading methodology: A diamond with Very Good polish and/or symmetry, for example, may receive an Excellent cut grade.
A GIA Diamond Grading Report contains the diamond’s full cut assessment, in addition to a diagram showing the diamond’s proportions and relative measurements. Consider the report an invaluable tool in helping you pick a dazzling diamond.
The official GIA Cut Scale for round brilliant cut diamonds. Illustration: GIA
While knowing a diamond’s cut grade is essential, it shouldn’t be a substitute for seeing a diamond in person. As mentioned above, a diamond cut grade represents a range. For example, two diamonds with an Excellent Cut Grade may look – and perform – very differently. In addition, a diamond will look different under various lighting conditions, so you should take it for a test drive, so to speak. Last, you need to fall in love with the diamond – and no report can substitute for what stirs your heart.
An Excellent cut grade makes this 2.03 ct round brilliant diamond mesmerizing. Courtesy: 1stdibs.com
Diamond cut is extremely important. So is diamond color. Learn about it, too, so you can pick a spellbinding diamond.
If you’re shopping for a diamond engagement ring, you’ve probably heard about diamond fluorescence, along with varying opinions about its pros and cons. Let’s dig into a few common myths about fluorescence and D-to-Z color diamonds.
In this blog, we cover:
Myth #1: All diamonds fluoresce
Myth #2: You can see diamond fluorescence – no matter the lighting
Myth #3: Diamond fluorescence can always be detected
Myth #4: Diamond fluorescence influences a diamond’s color grade
Myth #5: Diamond fluorescence is given a grade, just like color, clarity and cut
Myth #6: Diamonds only show blue fluorescence
Myth #7: Strong blue diamond fluorescence is bad
Myth #8: Diamond fluorescence detracts from a diamond’s sparkle and beauty
Myth #9: Fluorescence means the diamond is a “real” natural diamond
Myth #10: Fluorescence can make a diamond less durable
Myth #11: Diamond fluorescence does/doesn’t affect value
Myth #1: All diamonds fluoresce
FACT: The majority of diamonds do not fluoresce. In a study of more than 26,000 diamonds submitted for grading to GIA, researchers found that only approximately 25% to 35% of them exhibited some degree of diamond fluorescence when examined with a standard long-wave UV lamp. So, it’s likely that the diamond you’re eyeing does not fluoresce.
Myth #2: You can see diamond fluorescence – no matter the lighting
FACT: Diamonds that fluoresce only do so when they are exposed to invisible UV rays and other higher energy radiation sources such as X-rays and lasers. You might see your diamond fluoresce under a bright sun, in a tanning bed, at a dance club or in other places where strong fluorescent or black lights are used. But once the light source is removed, the diamond will stop fluorescing. Incandescent lighting will not cause a diamond to fluoresce.
When viewed with incandescent light, all the diamonds in these earrings appear to be the same color. Photo: GIA
When viewed with a UV lamp, the diamonds in the earrings show different degrees of diamond fluorescence. Photo: GIA
Myth #3: Diamond fluorescence can always be detected
FACT: Diamond fluorescence cannot always be detected. You need conditions where UV rays are present and the intensity of the fluorescence is strong enough to be observed. A reputable grading laboratory, like GIA, follows strict protocols to determine the presence of fluorescence. It also adheres to set standards in describing its intensity, to ensure objective and consistent reporting.
Fluorescent or not, this 1.42 carat (ct) diamond engagement ring, with diamonds lining the band, captivates with its bold, clean lines. Courtesy: 1stdibs.com
Myth #4: Diamond fluorescence influences a diamond’s color grade
FACT: In assigning a diamond color grade, GIA examines the gem in a highly controlled viewing environment, designed to minimize the influence of fluorescence and to produce an accurate and objective assessment of the diamond’s color.
However, the way you perceive a diamond’s color grade may be affected by the extent to which it fluoresces – in a positive way. In a diamond lower on the GIA D-to-Z color scale (say, I to N) with a yellow tint, moderate-to-strong blue fluorescence may cancel out some of the yellow for a better color appearance than what its color grade would indicate. See Myth #7.
Myth #5: Diamond fluorescence is given a grade, just like color, clarity and cut
FACT: Diamond fluorescence is not one of the 4Cs – like color, clarity, cut and carat weight – which describe the quality of a diamond. GIA considers fluorescence an identifying characteristic – additional information that helps distinguish one diamond from another.
GIA diamond grading reports describe the intensity of fluorescence as None, Faint, Medium, Strong and Very Strong. If the fluorescence is Medium, Strong or Very Strong, the color of the fluorescence will be noted on the grading report.
A GIA Grading Report describes the intensity of a diamond’s fluorescence as: None, Faint, Medium, Strong and Very Strong. Composite photo in UV: Maha DeMaggio/GIA. Composite photo in normal light: Harold and Erica Van Pelt/GIA
Myth #6: Diamonds only show blue fluorescence
FACT: Diamonds can fluoresce in a variety of colors. These include orangy yellow, yellow, orange, red, white and green. Variations in the atomic structure, such as the number of nitrogen atoms present, cause the phenomenon. Blue, however, is by far the most common color of diamond fluorescence.
These rough diamonds exhibit a range of colors when exposed to UV light. Photo: GIA
Myth #7: Strong blue diamond fluorescence is bad
FACT: GIA studied the influence of blue fluorescence on the appearance of a diamond under normal viewing conditions. The Institute found that average observers (meant to represent the jewelry buying public) could not consistently discriminate any fluorescence-related effects in the viewing environments most similar to those in which jewelry is purchased and worn.
However, GIA also found that strong blue diamond fluorescence could be beneficial. The results of its study revealed that, as noted for Myth #4, some strongly blue fluorescent diamonds were perceived to have a better color appearance than their color grade would suggest when viewed table-up, with no discernible trend table-down.
Bejeweled fireworks: Half the diamonds in this necklace (132 carats total weight) and the one earring (3.20 ct center stone) in this composite photo are shown under normal lighting conditions (left), and the other half of the necklace and the same earring are shown as they appear under a long-wave UV lamp (right). Composite photo: Harold and Erica Van Pelt/GIA. Courtesy: Harry Winston Inc., New York
Myth #8: Diamond fluorescence detracts from a diamond’s sparkle and beauty
FACT: Diamond fluorescence has little to no effect on a diamond’s sparkle, and research shows that it doesn’t impact beauty either.
A diamond’s sparkle is determined primarily by its cut, not by whether the diamond fluoresces or not. A diamond’s cut – that is, the angles and relative measurements of its facets, as well as its other proportions, design and craftsmanship – determines how well light performs when it strikes the diamond and how well it will sparkle.
Even strong blue fluorescence would not affect the beauty of this 1.29 ct E color diamond engagement ring in normal lighting. Courtesy: 1stdibs.com
MYTH #9: Fluorescence means the diamond is a “real” natural diamond
FACT: Absolutely not. The presence or absence of fluorescence should not be used as a DIY test to determine if your diamond is real. First, not all natural diamonds fluoresce under the standard UV lamp used by gemologists (see Myth #1). Second, some synthetic or lab grown diamonds do fluoresce to these wavelengths. Although differences have been noted in the intensity, color and pattern of fluorescence between natural and synthetic diamonds, there is overlap. Finally, some materials used to impersonate diamond – like cubic zirconia – can display fluorescence.
Synthetic diamonds made by the chemical vapor deposition method may display strong pinkish orange fluorescence (among other colors), with regions of strong blue or violet, when exposed to high-intensity ultra-short wavelengths. Photo: Wuyi Wang/GIA
Myth #10: Fluorescence can make a diamond less durable
FACT: A diamond that fluoresces under a standard UV lamp has the same structural integrity as one with no reaction to it. Nothing in the submicroscopic structures that cause fluorescence inherently weakens the diamond.
Myth #11: Diamond fluorescence does/doesn’t affect value
FACT: Jewelry professionals disagree about whether fluorescence adds to or detracts from the value of a diamond. Some trade professionals believe those very rare diamonds at the high end of the D-to-Z color scale that have extremely strong blue fluorescence are worth less than their nonfluorescent counterparts because the fluorescence can affect their transparency by giving them a hazy or milky appearance. Conversely, some traders pay higher prices for blue-fluorescing diamonds of a lower color grade because, as noted above, they believe the fluorescence masks the faint to very light yellow color of these diamonds.
Diamond fluorescence and its effect on value is not a simple question, and there isn’t a simple answer. We recommend that you compare diamonds in a variety of lighting environments and choose the stone that you like best. Ultimately, GIA believes the beauty of a diamond is truly in the eye of the beholder.
Wouldn’t it be awesome if this 1.67 ct center diamond fluoresced in a night club? Courtesy: 1stdibs.com
Is there a diamond fluorescence “fact” you’d like to verify? Leave us a comment below. In the meantime, if you enjoyed this post, you might like reading about common engagement ring myths.
With its graceful, tapered outline, a pear shaped diamond is an elegant and flattering choice for an engagement ring. Here are the essentials for selecting the perfect pear shape.
Jewelers consider the pear shaped diamond a “fancy shape,” meaning it’s a shape other than round. Reminiscent of a tear drop, a pear shaped diamond blends the best of the round and marquise diamond shapes.
Since the parts of a pear shaped diamond contribute to its beauty, you should get to know them. Then you can shop for a pear shaped diamond engagement ring with a discerning eye.
You’ll want to be able to name the parts of a pear shaped diamond when you’re looking at various stones. This shows the retailer you’re an informed buyer. Illustration: Peter Johnston/GIA
Look at the diamond face-up and pay attention to its outline. A pear shaped diamond should have gently rounded shoulders and wings. The wings should form attractive arches. If they’re too flat, they make the stone look too narrow. If they’re too rounded, they make it look short and stubby.
A bejeweled pair of pears: a 4.06 carat (ct) yellow pear shaped diamond is nestled against a 3.02 ct colorless diamond. The band, which flows from 18K white gold to yellow gold, echoes the colors of the stones. Courtesy: 1stdibs.com
The pear shaped diamond, like the round brilliant diamond, is faceted to deliver the most sparkle and brilliance. Here are the names of important parts of a faceted diamond, which you should know and are used in this blog:
On a black background, this 3.83 ct pear shaped diamond shines like a star in the night sky. Photo: Robert Weldon/GIA. Courtesy: Atelier Marisa
Like many other fancy shapes (such as the marquise or heart shape), a pear shaped diamond tends to hold more color than a round brilliant. Therefore, it is best to choose a diamond that is high on the GIA color scale or a fancy-color diamond.
Because pear shaped diamonds tend to hold more color than round brilliant diamonds, it is best to choose a diamond that is high on the GIA color scale or a fancy-color diamond like this 1.21 ct Fancy purplish pink diamond engagement ring set in 18K gold. Courtesy: 1stdibs.com
Symmetry is key to the overall beauty of gemstones, but it’s even more important in some fancy-shape diamonds like oval diamonds, heart shaped diamonds, marquise diamonds and pear shapes. To see if a pear shaped diamond is symmetrical, draw an imaginary line down the length of the gem and examine the two halves. The more closely they mirror each other, the better the symmetry is.
Notice how the shoulders, bellies and wings in the illustration below are identical on either side of the line, and how the shape, size and placement of the facets in each half of the stone mirror one another. This is an ideal pear shape. You can use the illustration as a guide when picking a pear shaped diamond.
Illustration: Peter Johnston/GIA
When GIA diamond graders evaluate the symmetry of fancy-shape diamonds, which includes pear shapes, they also look for things like a balanced and even outline. Certain types of asymmetry and uneven proportions are considered by most in the jewelry trade to have a negative effect on the appearance of a pear shaped diamond. These include:
Uneven shoulders and uneven wings are other variations that will detract from the appearance of a pear shaped diamond. The illustration below has both.
The uneven outline of this pear shape reveals the asymmetry of its shoulders, belly and wings. You might want to avoid a diamond cut like this. Illustration: GIA
You might run into the phrase “length-to-width ratio” (comparison of the length and width of the outline of many fancy-shape diamonds, determined by dividing the diamond’s length by its width and stated as a ratio, like 1.75:1). Many experts prefer a length-to-width ratio that lies in the range of about 1.50–1.75:1. Others in the trade believe that a ratio isn’t enough to convey a diamond’s beauty. You may want to let your heart and eye guide you.
Falling in love with any diamond is more than finding the perfect symmetry and length-to-width ratio. Are you infatuated with this 0.88 ct pear shaped diamond? Courtesy: 1stdibs.com
The placement of the culet on a pear shaped diamond can affect its appearance. It should be the same distance from the two sides of the diamond. A culet that is off-center will affect the diamond’s symmetry and is likely to make it less attractive. In some pear shapes, the culet is included in a keel line that extends down the length of the diamond where the pavilion facets meet. Like the culet, the keel line should be equidistant from either side of the diamond.
The culet on this pear shaped diamond is off-center. It should be symmetrically placed at the same distance from either side of the gem. Illustration: GIA
Note, too, whether the diamond has any inclusions, especially near its point, as this is the area of that is most sensitive to damage. In addition, if the pear shaped diamond has a larger table facet, inclusions could be more apparent, so good clarity is a consideration.
A poorly placed table facet can also make a pear shaped diamond look less attractive. For maximum brightness and fire, the table should be centered on the line of symmetry.
If the table is off-center, the crown facets on one side of the pear shaped diamond will appear larger than the facets on the opposite side. Illustration: GIA
Many pear shaped diamonds show a dark pattern that resembles a bow-tie. This pattern typically runs across the width of the stone from the center of the table. The bow-tie on a well-cut pear shaped diamond should be minimal, but there will still be good contrast between light and dark areas in the stone.
A bow-tie can vary from light gray to black. The darker or larger it is, the more it detracts from the face-up appearance of a pear shaped diamond. A bow-tie gets darker as the difference between a diamond’s length and width increases and pavilion angle variations (the measured angle between the pavilion main facet plane and the table plane) become more extreme.
If you find the bow-tie effect distracting, be sure to examine a variety of pear shaped diamonds from different angles under the lighting conditions in which the engagement ring will be worn. You may not be able to avoid a bow-tie altogether, but you should be able to find a stone in which it is subtle.
These pear shaped diamonds display a bow-tie effect, the dark area that extends across the width of each stone. Photo: Nicholas DelRe/GIA
The most vulnerable part of a pear shaped diamond is the point. This area can be protected by placing a V-prong on the point or choosing a bezel setting around the entire stone.
A V-prong protects the point – an area susceptible to chipping – of this 8.25 ct pear shaped diamond. Four more prongs hold the diamond securely in place. Courtesy: 1stdibs.com
A bezel setting ensures that the 0.40 ct pear shaped diamond is well protected. Courtesy: Doyle & Doyle
The traditional way to wear a pear shaped diamond engagement ring is to have the tip pointing away from you (down). According to many in the trade, this makes the finger look more slender. But tradition has its limits. Some brides choose to wear this shape with the point toward them (up). And some prefer a horizontal setting that gives this classic diamond shape a distinctive, contemporary look.
Like all matters of the heart, let yours decide which way the pear should point.
Whether the tip of the 1.34 ct pear shaped diamond points toward or away from you, an engagement ring like this will look spectacular on the finger. The center stone is surrounded by 43 radiant cut diamonds weighing 0.41 carats and 1.03 carats of sapphires. Courtesy: 1stdibs.com
Among the most elegant of the fancy shapes, a pear shaped diamond conveys both the delicacy of a single tear and the strength of the brightest star. While there are many factors to consider when searching for the perfect stone for your diamond engagement ring, it is a journey well worth taking. When deciding between different pear shaped diamonds, the overall appearance is more important than the specific proportion details. Often, what makes a pear shaped diamond attractive is a matter of personal taste. So enjoy looking at different pear shaped diamond engagement rings until you fall in love with the perfect one.
Before you go shopping, be sure to read our 12 tips for buying an engagement ring.
The term 4Cs we know today had its start in the early 1940s, as the brainchild of GIA founder Robert M. Shipley. A former retail jeweler, Shipley was fiercely committed to professionalizing the American jewelry industry. He established an institute (GIA) to provide jewelers with formal training and was a tireless advocate for greater knowledge, ethics and standards when it came to buying and selling gems.
Robert M. Shipley founded the Gemological Institute of America in 1931. Photo: GIA
Shipley developed the 4Cs as a mnemonic device to help his students remember the four factors that characterize a faceted diamond: color, clarity, cut and carat weight. The concept was simple, but revolutionary.
Throughout history, diamond merchants used a variety of different, usually broad, terms to talk about these four factors, rarely with any consistency. Terms such as river or water were used to describe diamonds that were the most colorless, with Cape assigned to pale yellow diamonds from South Africa’s Cape of Good Hope region. To describe clarity, they referred to diamonds as being “without flaws” or “with imperfections.” Cut was described as “made well” or “made poorly.” As a result, it was very difficult for jewelers to communicate those elements of value to their customers or for their customers to remember them. Only the term carat to describe weight has been used consistently from the 1500s to today.
Under Shipley’s direction, the term 4Cs became part of the American gem industry’s vernacular, popularized through advertising campaigns, lectures and GIA education courses. Within decades, they were integrated into the international nomenclature as well.
Jewelers welcomed Shipley’s innovation, but GIA did not stop there. Shipley’s successor as president, Richard T. Liddicoat (affectionately known as “RTL” by later generations of GIA staff) – along with colleagues Lester Benson, Joseph Phillips, Robert Crowningshield and Bert Krashes – expanded on the 4Cs.
Richard T. Liddicoat, president of GIA from 1952 to 1983, integrated the 4Cs into GIA’s curriculum and laboratory reports. Courtesy: Norman B. Samuels Portrait Photographers, Los Angeles
Their work included not only development of the now famous GIA D-to-Z Color Scale and GIA Clarity Scale for diamonds, but also the scientific methods and procedures for objectively grading a diamond’s quality.
A 2.78 carat (ct) D-color round brilliant diamond that is internally flawless is a wonder of nature. GIA invented the color- and clarity-grading terminology that is now used internationally to describe diamond quality. Photo: Robert Weldon/GIA. Courtesy: Rogel & Co. Inc.
Before the 4Cs and RTL’s contributions, a confusing alphabet soup was used to describe a diamond’s color. In communicating color quality to consumers, retailers used competing systems with descriptors like “A,” “AA” and “AAA.” There was virtually no agreement among firms as to what was considered an “A” grade. Most diamond wholesalers used terms like rarest white and top Wesselton, in addition to those mentioned above. In short, there were no standards that allowed for consistent evaluation and comparison.
Since the 1930s, GIA had been working on an accurate, objective color-grading system for colorless to light yellow diamonds. The goal was to develop a system based on absolutes, instead of relative terms and vague descriptions. In 1953, GIA, under RTL’s direction, introduced the GIA D-to-Z color scale, choosing the letter “D” for the top grade (colorless) precisely because the letter had negative associations and so was unlikely to be misinterpreted or misused.
GIA’s D-to-Z Color Scale is the industry standard for grading the color of colorless to light yellow diamonds.
In addition to establishing a color scale, RTL and his colleagues defined the methods that would be used to grade a diamond’s color accurately and consistently. These included determining the type of lighting and neutral background with which a diamond should be evaluated, prescribing precisely how the diamond should be held and viewed, and developing master stones: sets of diamonds of predetermined color value against which the subject diamond is carefully compared.
The D-to-Z diamond color terminology RTL and his colleagues pioneered is now used around the world, and strict color-grading procedures are followed by the GIA laboratory.
Understanding the 4Cs is essential if you’re shopping for a diamond engagement ring. This one has a 1 ct center stone surrounded by four diamond side stones. Melee diamonds in a halo setting frame the design and continue down the shoulders of the ring. Courtesy: Sylvie Collection
The GIA Clarity Scale contains 11 grades that range from Flawless (FL) to Included (I3).
Diamond clarity grading was another area that was plagued by inconsistencies in terminology and methods. Some trade professionals used terms like perfect in addition to without flaws and with imperfections, which were vague and imprecise. Others used terms we recognize today, such as VS, VVS, and included, but without any agreed-upon definitions. RTL and Benson used these terms in creating a clarity-grading scale, but defined precise categories and expanded the number of grades within each category to account for the array of diamonds in the market. Fine-tuned in subsequent years, the GIA Clarity Scale today consists of six categories ranging from Flawless to Included and contains 11 specific grades.
This precision in clarity grading was made possible by another GIA innovation: the introduction of the gemological microscope as a tool for clarity grading. Using the microscope, GIA graders plot the inclusions and blemishes in all diamonds for which a full GIA Diamond Grading Report has been requested.
A plotting diagram, a feature of all GIA Diamond Grading Reports, uses specific symbols to map a diamond’s various inclusions and blemishes.
The impact of Cut – how well a diamond interacts with light – was another attribute that RTL and his associates wanted to better explain and standardize. Originally, RTL turned to the work of Belgian mathematician and diamond cutter Marcel Tolkowsky to help determine “ideal” proportions for a round brilliant cut diamond. RTL’s contribution included a rating system with deductions for proportions that deviated from those.
Because of GIA’s efforts to standardize the evaluation of diamond cut, round brilliants such as these can now be objectively graded. Courtesy: Supreme Jewelry
GIA’s system for evaluating cut has been modified over the decades. In 2006, after years of extensive research that included advanced computer modeling and observational studies, GIA introduced the GIA cut grading system for round brilliant cut diamonds. Today, the GIA Cut Scale, ranging from Excellent to Poor, describes how successfully a diamond interacts with light to deliver the brightness, fire and scintillation we associate with a fine round brilliant.
The GIA Cut Scale assesses the overall cut quality of each diamond individually, taking into account such features as proportions, table size, polish and symmetry.
Many factors contribute to the evaluation of a diamond’s cut, including the size of the facets, girdle thickness and total depth.
Using the latest scientific advances to establish grading standards that provide consistent, repeatable results, GIA has revolutionized the jewelry industry. With the framework provided by the 4Cs, it has transformed the way diamond quality is determined and communicated and, ultimately, how diamonds are bought and sold.
These standards are strictly followed by the GIA laboratory in its nine locations worldwide. They allow GIA to deliver objective, consistent diamond grading results anywhere in the world. It is important to note that although the terminology introduced by GIA has been adopted by other laboratories worldwide, only the GIA laboratory has the proprietary equipment and procedures to grade diamonds to these standards.
All this critical information becomes part of a GIA Diamond Grading Report. With it, you’ll know the essential facts about the diamond you’re considering.
The GIA Diamond Grading System provides a complete description of diamonds such as this 1.37 ct H-color, VS1-clarity round brilliant in a platinum Tiffany & Co. setting. Courtesy: 1stdibs.com
Why ask for a GIA Diamond Grading Report? Read more and decide for yourself.
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