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.
Looking for the perfect diamond engagement ring? You’ll need to know about the 4Cs of diamond quality, metal characteristics, setting styles and more.
Follow these 10 tips for buying an engagement ring to make a smart purchase:
The diamonds in this image show Poor, Good and Excellent cut grade from left to right. Photo: Kevin Schumacher/ GIA
The first tip for buying a diamond engagement ring is to know the 4Cs: Color, Clarity, Cut and Carat Weight. Created by GIA, the 4Cs are the global standard for assessing the quality of diamonds and allow you to compare one diamond to another.
In brief, the 4Cs are:
Once you understand what the 4Cs mean, the next step is to ask yourself “Which C is the most important to me?” Prioritizing the 4Cs will help you quickly eliminate some diamonds from your search and hone in on the diamond that’s right for you. It will also help you work with your budget, knowing which C you are willing to spend more on and which you are willing to compromise on.
These fancy diamond shapes include, from left to right: cushion cut, square emerald cut (aka Asscher cut), emerald cut, radiant cut, oval cut, marquise cut and pear cut. Photo: Robert Weldon/GIA
Before you start shopping for an engagement ring, you should understand the difference between a diamond’s shape and its cutting style. Shape describes a diamond’s outline when viewed face up. The most popular diamond shape is round. But there are other shapes—known as fancy shapes—which include the marquise, pear, oval, rectangle, square and heart.
*Tip: Round brilliant diamonds tend to cost the most of all the shapes and cut styles. Choosing a fancy shape can be a good way to save money and choose a unique center stone.
Cutting style refers to how a diamond’s facets are arranged. The brilliant cut is popular due to how it maximizes a diamond’s brightness. This cut style can be seen on a range of shapes, from round to oval to square (princess cut) to marquise. The most popular shape and cut combination by far is the round brilliant cut, which has 57 or 58 facets.
The step cut is another popular cutting style. Steps cuts have long, sleek lines, which gives them an elegant, sophisticated gleam. A popular step cut is the emerald cut—a square or rectangular shape with by concentric rows of parallel facets and beveled corners. In contrast, a radiant cut diamond also has a square or rectangular shape but is cut in the brilliant style.
*Tip: Step cuts tend to show their color and clarity more, while brilliant cuts are better at hiding color and inclusions. If you are purchasing a step cut, considering going up in color and clarity.
Emerald cut diamonds are known for their elegant, gleaming hall-of-mirrors effect rather than brilliance. Courtesy: Alrosa
Daylight, fluorescent light, spot lighting – a diamond looks very different under various lighting conditions. Many jewelers use white spotlighting, which brings out a diamond’s brilliance and fire and will make most diamonds look dazzling. Most day-to-day situations do not consist of such dramatic lighting, however. Be sure to see how your diamond performs under average lighting conditions, such as outdoors in light or shadow or under the diffused, fluorescent light of an office workplace or the warm, diffused lighting common in most homes.
Note that fluorescent lighting brings out a diamond’s brightness, while incandescent lighting brings out a diamond’s fire.
Mixed fluorescent and incandescent lighting is ideal for showing both a diamond’s brilliance and fire. Courtesy: Alrosa
Popular jewelry metals include yellow gold, rose gold, white gold and platinum. Gold and platinum have different characteristics. Their colors can also change the appearance of a piece of jewelry and set off the color of a ring’s gemstones differently.
Metal Types:
Yellow gold is a classic. It has been used in jewelry for thousands of years. It enchants because of its color, rarity and luster (the appearance of a material’s surface in reflected light). Pure gold is soft, so it is typically alloyed with other metals. Karat is the term used to state gold’s fineness, which is based on 24 parts. Gold that is 75% pure—18K gold—is 18 parts gold and six parts of other metals to create an alloy. The most popular fineness in the U.S.—14K gold—is 14 parts gold and 10 parts of other metals.
*Tip: Metals with a higher amount of gold will have richer color, be heavier, softer (slightly more prone to dents and scratches) and more costly.
Rose gold has been a popular choice for many years. It was often used in engagement rings during the Retro era (1935 to the 1950s). It is usually made by alloying gold with copper and silver, which is what gives it its warm, pinkish tone. Companies closely guard their special blends.
Moval Collection by Rahaminov Diamonds. Ring in 18K rose gold with a total of 5.31 carats of diamonds.
White gold is made by alloying pure gold with white metals such as nickel or palladium among others. It is a beautiful and durable choice for engagement rings. White gold is usually plated with rhodium, a platinum group metal, to give it a whiter finish. This can wear away over time. White gold jewelry typically requires replating, or the slightly yellowish color of the white gold underneath may start to show through. This is easy and relatively inexpensive to do, however; simply ask your local jeweler for this service.
Platinum is a slightly grayish white metal that is extremely durable and corrosion resistant. Because platinum is soft in its pure state, it is typically alloyed with other platinum group metals such as iridium or ruthenium. Courtesy: Rahaminov
According to the U.S. Federal Trade Commission, only jewelry containing at least 95% platinum (5% alloys) can be marked “Platinum;” other platinum alloys are marked according to the Federal Trade Commission Guidelines. Platinum is generally more expensive than gold, but it is also hypoallergenic and more durable.
How Metal Color Affects Gemstone Color
White gold and platinum are good choices for diamonds graded in the colorless to near-colorless ranges–D through J on the GIA color scale—as they highlight the diamond’s colorlessness.
The color of the metal reflects throughout the diamond. Setting a colorless diamond in yellow prongs can cause it to look more yellowish in appearance. Gold and rose gold settings tend to benefit diamonds with lower color grades or colored diamonds or colored stones as they can help enhance the color of the gemstones. If you have a diamond with a distinctively yellow or brownish tint, a white gold or platinum setting might conversely emphasize the color of the stone due to contrast.
If you love the color of yellow gold or rose gold, use white gold or platinum prongs or bezels to set the diamonds and pair with yellow gold or rose gold bands. This way, the diamonds will appear more colorless while you get the style that you want.
The diamonds in this ring are set in platinum to showcase their colorlessness. Rose gold bands are woven throughout for contrast. Courtesy: Sylvie Collection
In jewelry, diamonds are held in place by settings. The setting has two jobs: to hold the diamond in place and to protect it from damage. Different settings offer different degrees of protection.
Here are two popular types of settings:
The six-prong setting in this solitaire engagement ring provides extra security for the diamond. Courtesy: JK & Co Jewelers
This ring has a bezel set princess cut diamond, surrounded by a diamond halo with latticework and millgraining.
Side stones are a dazzling way to dress up an engagement ring and make it look bigger. Popular choices include making the ring a three-stone ring, adding a halo, including channel, pavé or bead set diamonds along the shank of the ring, and adding colored gems or birthstones. If you want diamond side stones, choose those with 4Cs grades similar to that of the center stone. Having a similar color grade is especially important if you want the stones to match.
Emerald is the May birthstone. These pear-shaped emeralds give this ring a unique look, and the diamond halo adds a luxurious touch. Photo: Ziva
Three-Stone Ring: The three-stone ring, also known as the trinity or trilogy ring, symbolizes friendship, love, and fidelity, or past, present, and future. To add to its romantic connotation, you can incorporate birthstones for a personal touch.
Sapphire is the September birthstone. It symbolizes fidelity and nobility, and the color contrast can really make the center diamond pop. Courtesy: Omi Privé
Halo Setting: Adding melee diamonds around your center stone and on the shank can make the center stone look larger and add more sparkle to your engagement ring. Most rings have a single or double halo but there’s no limit to the number of halos you can add!
This ring features a 0.42 carat marquise-cut pink diamond center stone set in a triple-halo of pink and white round brilliant diamonds. The triple-halo makes the ring look a lot larger and so does the split shoulder band set with melee diamonds. Courtesy: Yael Designs
Cluster Setting: Cluster settings are a great way to maximize sparkle at a relatively affordable price. Smaller diamonds cost less than large ones and can be set in a way to create the illusion of a single larger diamond. Small diamonds also be arranged in unique designs.
This cluster-style ring has a small diamond in the center surrounded by a halo with more small diamonds set in a flower motif. The additional diamonds dramatically increase the size of this ring and add sparkle throughout. Courtesy: Kat Florence Atelier
What style of ring are you looking for—vintage, modern, timeless, Bohemian, romantic? Know your time periods and motifs or add personalized touches for a stand-out ring.
This Belle Époque ring from the early 1900s features a 2.02 carat D Internally Flawless diamond surrounded by old European-cut diamonds set in platinum accented with millgraining. Courtesy: Lang Antiques
Vintage and Modern Vintage: Vintage styles are making a comeback, or perhaps they’ve simply never gone out of style! For an Edwardian style engagement ring, go for vintage motifs such as scrollwork, millgraining, and engraving. Many setting styles are rich with meaning. The toi et moi ring, French for “you and me,” has been popular for centuries. It features a ring with two gemstones representing the couple coming together. This motif was made famous by Napoleon who gifted his future-empress Josephine with a sapphire and diamond toi et moi ring.
Napoleon Bonaparte gave this diamond and sapphire toi et moi engagement ring to Josephine de Beauharnais in 1796. Photo: PATRICK KOVARIK/AFP/Getty Images
This modern toi et moi ring features a 4.06 carat pear-shaped Fancy brownish yellow diamond and a 3.02 carat pear-shaped colorless diamond. Notice that the yellow diamond is set in yellow gold while the colorless diamonds are set in white gold. Courtesy: 1stdibs.com
If you’re looking for period jewelry, consider Art Deco style engagement rings and Art Nouveau style engagement rings. Also consider diamonds with older cut styles such as the rose cut or the Old Mine cut.
This ring features three rose cut diamonds and sapphire melee. Rose cut diamonds give rings a mellow, vintage look. Courtesy: Shelly Purdy Studio
Heart Rings: Heart motifs have been popular since medieval times and have never gone out of style since. Not only do they symbolize love, heart shaped diamonds are typically more affordable than round brilliants. It is a unique option that will definitely make a ring stand out.
This ring features a heart-shaped yellow diamond with a yellow diamond halo and a split shoulder shank. Courtesy: 1stdibs.com.
Bohemian Rings: Bohemian style rings play with unexpected gemstone shapes, setting styles and silhouettes, such as geometric diamond cuts, black diamonds, and rings with open shapes. Some are edgy; others have a more romantic vibe.
This rose gold ring has a chevron-shaped band above a 1.25 carat pear-shaped diamond. The pear diamond and chevron gives this ring a vintage feel. The claw prongs and suspended look are distinctly modern. Courtesy: Brilliant Earth
Stacked Engagement and Wedding Rings: Will your diamond engagement ring be worn alongside a wedding ring? Make sure that their silhouettes match and that the two rings fit together. A popular trend now is stacking multiple rings together with the engagement ring to complement it in design.
This custom stacked engagement ring consists of diamonds surrounded by opals, aquamarines and sapphires. Courtesy: Maggi Simpkins Designs
Custom Rings: Personalization makes rings feel unique and memorable. Consider a custom engagement ring for a one-of-a-kind ring that celebrates the special moments in your relationship.
Once you’ve picked out a diamond and chosen a style for the ring, the next step is to measure the wearer’s ring size. The best way to do this is with a ring sizer, which is a series of plastic or metal rings in different sizes that you try on. Your jeweler will have a ring sizer and can help you find the perfect fit. If you want the ring-making process to be a surprise, try guessing ring size by borrowing a ring your fiancée or fiancé already owns. Trace the inner circle on a piece of paper. Or slide it down one of your own fingers and draw a line where it stops. A jeweler can help you to estimate the approximate ring size. Note that ring size varies from finger to finger, so using this method will only give you an approximation.
The good news is that most rings can easily be resized up or down by a size or two. Resizing more than that may be more difficult depending on the style of the ring. Solitaire rings are easy to resize, while rings with pavé or bead-set diamonds or other details on the band will require more work.
Choosing a knowledgeable, accredited jeweler will ease your decision-making process. Photo: andresr/E+/Getty Images.
Since an engagement ring is a significant investment, you’ll want to buy it from a jeweler you can trust. Your jeweler should be armed with expert training, be open to questions and be able to explain how to buy a diamond in clear, simple language. Tip – start by looking for a jeweler who has earned a credential from a highly recognized and internationally accredited program, such as the GIA Graduate Gemologist (GG) or Applied Jewelry Professional (AJP) diploma programs. As your personal diamond-buying guide, an educated jeweler will not only explain the 4Cs of Diamond Quality, but will also be able to demonstrate the differences between apparently similar diamonds. They will encourage you to compare a number of diamonds that fall within your budget. The GIA Retailer Look Up can help you find local jewelers who carry GIA-graded diamonds or have GIA-trained staff.
The GIA Retailer Lookup is a quick, easy way to find local jewelers who carry GIA-graded diamonds or have GIA-trained staff.
A diamond grading report from an independent, scientific laboratory such as GIA is more than a document containing important information. Purchasing a diamond with a GIA report ensures that you know the identity and quality of your diamond. It tells you whether your diamond is natural and whether it has received any treatments. GIA Diamond Grading Reports are also used by appraisers to determine a diamond’s value if you want to insure your diamond engagement ring.
At GIA, we know diamonds. We created the 4Cs of diamond quality and the GIA International Diamond Grading System™ used worldwide for grading diamonds. Top museums and auction houses trust us to evaluate their finest treasures, and our reports are recognized internationally. We apply the same passion and precision we use in grading these world-famous diamonds to grading every diamond—including yours. Our expertise is reflected in a variety of diamond reports, ranging from the GIA Diamond Dossier to the GIA Diamond Origin Report. Learn what each report can tell you about your diamond and insist on one when you are ready to make your purchase.
A GIA Diamond Grading Report let you know the identity and quality of what you are buying.
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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The origin of wedding rings is a fascinating one. The tradition of exchanging rings dates back 3,000 years, while the first diamond wedding ring was recorded in the will of a widow who passed in 1417. Why are rings, especially diamond rings, the ultimate symbol of romance? (more…)
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.
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