How Does Diamond Shape Affect Price

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In the first place, whatever diamond shape you prefer is a matter of personal preference. However, certain shapes of diamonds will perform better than others. In other words, the shape of your diamond will affect the volume of light return and the sparkle intensity.

From that perspective, the modern round brilliant cut diamond performs better than any other option. That’s because the symmetrical shape and uniform facet structure make it easier to optimize it for light performance.

Although this may be true, you should not select a round diamond just because it performs better and sparkles more. As a matter of fact, there is more to consider when buying a diamond than light performance. For one thing, each unique shape is going to reflect light differently than another.

Diamond Shapes Buying Guide Featuring Blue Nile Engagement Rings.

Choose Your Favorite Shape from Blue Nile.

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The Most Popular Diamond Shapes:

Needless to say, that of these popular facet structures produces fire and brilliance to varying degrees. In addition, there are specific guidelines and proportions charts for each unique shape. Although that may be true, we're going to show you how to maximize the performance for your personal favorite.

The Difference Between Diamond Shape and Cut:

As a matter of fact, there is a difference between the shape of the diamond and the cut quality. In the first place, the diamond shape is the outline of the diamond or geometric shape. Whereas the cut quality is the cumulative effect of polish, symmetry, proportions, and optical precision.

James Allen Ring Style 17307R14

Oval Halo Diamond Ring by James Allen.

Some diamond shapes have facet structures that are easier to optimize for light performance. That is why it’s easier to find AGS Ideal-0 cut rounds, cushion, emerald, and princess cut diamonds.

Whereas it is much harder to produce ideal cut diamonds in other fancy shapes. That’s because differences in the length of the facets affect how evenly light reflects throughout the body of the stone.

A good example of this is the ever-popular oval-shape diamond. The picture on the left shows an oval-shape diamond set in a 14k rose gold halo from James Allen.

In the first place, the setting is absolutely stunning! However, I want you to notice the difference between the light and dark sections of the diamond.

 As a matter of fact, the difference in the size and shape of the facets is creating this effect. Although this may be true, this tutorial on oval-shape diamonds reveals why some look better than others. However, I'll give you a hint, the elongated shape of oval diamonds affects how light reflects through the stone.

The Most Popular Diamond Shapes:

In the event that you’re looking for an engagement ring, you might ask what is the most popular diamond shape? As a matter of fact, the modern round brilliant is the most popular shape diamond.

If you’re looking for a round diamond, then I have some insight that you’ll find interesting. At least if the sparkle factor of the diamond is of critical concern to you. In that event, you should know that Brian Gavin holds the patent for maximizing light performance in the modern round. As a matter of fact, he’s the only diamond cutter in the world who can make that claim.

Although that may be true, other shapes like cushion-cut and princess cut diamonds are also very popular. The graphic below from Ritani shows the popularity of different shapes in terms of their sales:

Popular Diamond Shapes

Round Diamonds from Ritani.

Popular Diamond Shapes

Ritani Fancy Shape Diamonds

Popular Diamond Shapes

Fancy Shape Diamonds from Ritani

Obviously, the popularity of each unique shape will vary depending on the source of the information. As a matter of fact, the majority of people buying diamonds from Brian Gavin choose a round brilliant. However, that is also the shape that Brian Gavin is best known for producing.

Be that as it may, they also produce other shapes like ideal cushion, emerald, and princess cut diamonds. As a matter of fact, Brian Gavin completely redesigned these shapes to maximize light performance. Under those circumstances, you literally won’t find anything comparable to them anywhere else.

Brilliant Cut vs Step Cut Diamonds:

From the perspective of diamond cutting, there are three basic facet structures or configurations:

  1. 1
    Brilliant Cut.
  2. 2
  3. 3
    Mixed cuts.

Obviously, the modern round brilliant cut diamond is an example of the first type of faceting style. As a matter of fact, any shape that incorporates a lower girdle half and main facets is a brilliant cut. The diamond cutter creates a spectacular light show by combining facets of different shapes and sizes.

Whereas the Asscher and Emerald shapes are both step-cut because the facets step down sequentially. In that case, the facets tend to be square or rectangular and are arranged parallel to each other. As shown in these photographs of a Brian Gavin Signature Emerald cut diamond:

Brian Gavin Signature Emerald Review Clarity

Brian Gavin Signature Emerald Cut Diamonds

ASET Brian Gavin Signature Emerald Cut Diamond

Brian Gavin Signature Emerald ASET Scope Image

Ideal Scope Brian Gavin Signature Emerald Cut Diamond

Ideal Scope Image for BGD Signature Emerald

As you can see, the facets are rectangular in shape and extend outward in a parallel configuration. In that event, these emerald cuts are what is known as a step-cut diamond. Be sure to read this tutorial on how to use the ASET Scope. Because it will explain how to interpret the image in the middle.

As a matter of fact, we use ASET and Ideal Scope images to judge the degree of light performance. Under those circumstances, this is probably the best example you’ll ever see in a step-cut diamond.

Brilliant Cut Diamonds:

Obviously, the modern round brilliant is a brilliant-cut diamond. In other words, the facets are arranged in a cone-like form that maximizes the sparkle factor. Although this may be true, the volume of light return depends on the pavilion angle. While the crown angle will dictate the balance of brilliance and dispersion.

Other shapes like the cushion, princess, oval, marquise, pear, and radiant are examples of brilliant-cut diamonds. Each of these unique shapes will reflect light in different patterns. In addition, the proportions of the diamond will affect the volume of light return and sparkle factor.

ASET Scope James Allen Cushion Cut Diamond

James Allen Cushion Cut Diamond ASET

As a matter of fact, the Brian Gavin Signature Cushion cut diamond rivals the performance of his round brilliant cuts. However, this does not seem to be the case with generic cushion shape diamonds. As a matter of fact, most of the cushions that I see leak a lot of light.

The ASET Scope image on the left is a good example of how most cushion cut diamonds leak light. In this case, this is a 2.01 carat, F-color, VS-1 clarity, cushion cut diamond from James Allen. As you can see, the ASET Scope image contains a lot of transparent and black areas. In that case, we can be certain that it is leaking a moderate amount of light.

Be that as it may, this type of light leakage is typical of most cushion cut diamonds. That’s because this shape is very difficult to optimize for light performance. Of course, you’ll find that some diamonds perform better than others. This is why you should insist on seeing ASET and Ideal Scope images before you buy a diamond.

Emerald and Square Shape Step-cut Diamonds:

ASET Asscher Cut Diamond

ASET for Nice Ice Asscher

As a matter of fact, emerald and square shape diamonds are the most popular step-cuts. The ASET Scope image for this Asscher cut diamond on the left makes it easier to see the facet structure. In addition, the different colors give us an idea of how light is reflecting throughout the diamond.

In the first place, you’ll notice that this Asscher is not leaking as much light as the cushion cut. Although that may be true, the reality is that most Asscher cut diamonds do leak a lot of light.

Be that as it may, this one happens to be leftover from our personal inventory. As such, it’s kind of a rare specimen and represents the high-end of the performance spectrum. Click here for more Asscher cut diamond buying tips. By the way, this is a 1.19 carat, E-color, VS-2 clarity, Asscher from Nice Ice.

Diamond Prices 101:

In the first place, there are several factors that determine the price of a diamond. The obvious characteristics are commonly known as the 4C’s of diamond grading:

  1. 1
    Carat weight.
  2. 2
    The Clarity.
  3. 3
  4. 4
    The Cut (quality).

As a matter of fact, this is what the majority of people focus on when buying an engagement ring. Although that may be true, the last characteristic known as cut happens to be the most important. Be that as it may, most people will confuse cut with shape and that is where they go wrong.

With that in mind, it’s important to realize that the diamond shape is not the same as the cut quality. Under those circumstances, the shape of the diamond is literally nothing more than personal preference. However, the diamond cut quality will dictate the degree of light performance and sparkle factor.

Another key point is that cut quality can affect diamond prices by up to sixty percent! In other words, there is probably a good reason why one diamond seems more or less expensive than another. That is of course assuming that the other characteristics, such as carat weight, color, and clarity are the same. In which case, that old saying about there being no such thing as a free lunch is probably true.

How Diamond Shape Affects Price:

In the event that you heard that fancy shape diamonds are less expensive than rounds, it’s basically a half-truth. To begin with, the price of fancy shape diamonds does tend to be lower per carat. At the same time, they tend to face-up smaller because there is more carat weight hidden in total depth. In other words, the price of a one-carat oval might be cheaper than a round brilliant. However, you’re going to have to buy a larger carat weight to get the same visible surface area.

Under those circumstances, you’ll have to do some comparison shopping to figure out which diamond shape is right for you. However, I generally find that things end up costing about the same once the average outside diameter is considered. With that in mind, I urge you to choose a shape that you like and run with it.

Although this may be true, the difference in the price of rough material is part of the equation. As a matter of fact, the rough material used to cut a round diamond is more expensive. That’s because the rough is more uniform and lends itself better to the symmetrical shape. Whereas princess cut diamonds are frequently cut from the scrap leftover from the round diamond cutting process. In fact, it’s the top corner of the rough that is sawn off when the table facet is fashioned.

Are Fancy Shape Diamonds Less Expensive?

According to this price comparison by Blue Nile, you can save up to 25% by choosing a fancy shape diamond. That is of course in comparison with the price of buying a round diamond with the same characteristics.

In this case, the comparison includes diamonds that weigh between 1.00 to 1.05 carats. Other characteristics include G-color, VS-2 clarity, and Very Good Polish and Symmetry.

Diamond Prices for Blue Nile Diamonds

Examples of Blue Nile Fancy Shape Diamond Prices

In the first place, it’s important to realize that there can be many reasons for these price differences. Not the least of which is the diamond shape, but many different things factor into diamond prices.

For one thing, the overall cut quality can influence the price by up to sixty percent. That includes the basics like polish, symmetry, and proportions, but also the degree of optical precision. The latter of which is not something that the labs consider as part of the grading process.

Proportions, Performance & Price:

In the event that you want a spectacular looking diamond, then you should focus on the proportions. As a matter of fact, the proportions of a diamond will dictate the light return and sparkle factor. Although that may be true, it’s the degree of optical precision that locks everything into place.

While the best proportions for a diamond vary by shape, it’s much easier to judge optical precision. After all, the reflector scopes that we use to judge cut quality are going to reveal any inconsistencies.

In that case, an ASET or Ideal Scope will show us the degree that a diamond is leaking light. At the same time, we can use a Hearts and Arrows Scope to see the consistency of facet structure.

Be that as it may, it’s important to remember that estimating light performance by proportions only works for rounds. Under those circumstances, the symmetrical and uniform facet structure makes for a reliable mathematical model.

However, the facet pattern and layout for fancy shape diamonds literally differ from stone-to-stone. In which case, the proportions of a fancy shape diamond are only the beginning of a long and perilous journey.

Although that may be true, you’ll find that the production of certain diamond cutters is better than others. With that in mind, you should check out Brian Gavin if you’re looking for these shapes:

Length to Width Ratio:

In the first place, every fancy shape diamond will have a slightly different shape or outline. As a matter of fact, each one will have a unique shape depending on the measurements. Under those circumstances, you can use the length to width ratio to get an idea of what it looks like.

In other words, you can use a simple mathematical formula to determine how a fancy shape diamond will look. With that in mind, I want you to think about a princess cut diamond. In the first place, most people tend to think that princess cuts are square.

In that case, the length and width of the diamond would be relatively the same. However, some princess cut diamonds are more rectangular in shape.

How to Calculate the Length to Width Ratio:

ASET for Brian Gavin Signature Princess Cut Diamond

ASET for Brian Gavin Signature Princess.

As a matter of fact, it’s relatively easy to calculate the length to width ratio of a diamond. In the first place, you’re just going to divide the length of the diamond by the width. Let’s use this 1.045 carat, G-color, VS-1 clarity, Brian Gavin Signature Princess cut diamond as an example.

According to the Diamond Quality Document it measures 5.46 x 5.41 x 4.15 millimeters. In this case, the length is 5.46 mm and you’ll divide that by the width which is 5.41 mm. Under those circumstances, the sum is 1.009 which we’ll round off to 1.01:1.00.

In that event, we know that this is a square princess cut diamond. As a matter of fact, a perfect square is a length to width ratio of 1.00:1.00. At the same time, you can also use the ASET image on the left to verify the shape.

Obviously, this Brian Gavin Signature Princess cut diamond is pretty darn square! In addition, we know that it’s going to be extremely bright and full of life.

After all,  the ASET Scope image is showing a lot of red that is an indication of primary brightness. At the same time, the ASET confirms that light is reflecting throughout this diamond evenly.

Pandora’s Box of Diamond Shapes:

When you set out to buy a fancy shape diamond, it’s a bit like cracking open the lid on Pandora’s Box. Under those circumstances, you never really know what to expect. In the first place, seemingly slight differences in characteristics can have dramatic effects on diamond prices.

Secondly, the reality is that there are several different facet patterns for each classification of fancy shape. Whereas the modern round brilliant cut diamond has 58 facets if you count the culet. The basic structure of a round brilliant consists of four sections:

  • Crown (the top section).
  • The girdle edge (middle).
  • Pavilion (the lower half).
  • The culet (bottom point).

Under those circumstances, the size and shape of the facets is relatively the same. In which case, it’s easier to optimize round brilliant cut diamonds for light performance. Whereas there are a lot of variables in the facet structure of fancy shape diamonds.

Although this may be true, the proportions and degree of optical precision still factor into the equation. For one thing, the opposing angles of the diamond have to be right to maximize light return. At the same time, any variance in the size, shape, or alignment of the facets will cause light leakage. For that reason, we use special reflector scopes to reveal issues pertaining to Azimuth Shift.

Modified Brilliant Fancy Shape Diamonds:

As a matter of fact, most people tend to think of diamonds in terms of shape. However, very few people realize how many variables there are within each of those classifications. On the one hand, the shape is the basic geometric outline of a diamond. At the same time, there are usually several different facet structures commonly available.

For example, here are the most common pavilion section facet patterns for oval-shape diamonds:

Oval-cut diamond pavilion facet diagrams

Popular Oval Pavilion Facet Structures.

In this case, there are fifteen distinctly different versions of the modern oval brilliant-cut diamond. By the way, this illustration is from the American Gem Society Laboratory list of diamond shapes.

The Unique Look of Diamond Shapes:

Under the circumstances above, each of those configurations is going to reflect light differently. At the same time, there is an equal number of options available for the crown section. With this in mind, you can see how many different facet patterns exist just for oval-shape diamonds. Of course, the same principle applies to all the other fancy shape diamonds as well.

Obviously each combination of different facet designs is going to produce a look that is truly unique. In the first place, the number of facets is a variable that is constantly changing. Secondly, the size and shape of the facets are subject to change depending on the needs of the cutter.

In other words, they’re going to adjust things in order to maximize the retention of carat weight. After all, the primary goal of most diamond cutters is to maximize the yield and produce higher profits.

Where to Buy Fancy Shape Diamonds:

Obviously, the internet is swarming with diamond dealers and all of them claim to offer the best diamonds. Under those circumstances, it can be difficult to know who to trust. Especially since most of them are simply mirroring the inventory from the same suppliers.

As a matter of fact, some of the biggest diamond dealers online are working off virtual inventory. For example, the majority of diamonds from these companies are not in-house:

Although that may be true, they might have the exclusive rights to represent those diamonds online. In which case, your local jeweler or another internet dealer might not have access to them. Under those circumstances, these dealers are able to offer an extensive inventory of diamonds for you to choose from.

The Largest Inventory of GIA Excellent Diamonds:

Oval-shape diamond

Oval-shaped Diamond from Blue Nile.

As a matter of fact, Blue Nile offers the largest selection of GIA graded diamonds. In this case, it is largely because they have exclusive distribution contracts with some of the biggest cutting houses. Although that may be true, they also tend to have great prices and offer a generous return policy.

In addition, Blue Nile generally provides a clarity photograph and high-resolution video. For example, here is the clarity photograph for this oval shape diamond from Blue Nile.

As a matter of fact, this diamond has proportions within the range I prefer. The total depth is 59.7% and it has a 55% table diameter.

Unfortunately, the GIA Laboratory does not provide crown or pavilion measurements for fancy shape diamonds. Thankfully, I was able to find this diamond in the multiple listing service that we use to trade diamonds globally. In that case, I was able to determine that the pavilion depth is 43% and the crown height is 13.7%.

Under those circumstances, we can see that the measurements meet the guidelines for the Class 1A Ideal Cut proportions rating. Here is the proportions chart for oval shape diamonds created by Gemologist David Atlas. In which case, we can be reasonably confident that this diamond is going to perform well. Of course, I would still like to have an ASET Scope image to verify the degree of light performance.

Cushion Square Cut Diamonds:

Brian Gavin Signature Ideal Cushion Cut Diamond

Hearts Pattern Brian Gavin Signature Cushion

In the event that you’re looking for a cushion square-cut diamond, you owe it to check out Brian Gavin. As a matter of fact, the Brian Gavin Signature Cushion cut diamonds rival the performance of a super ideal round.

In other words, this is the way to go if you want maximum light performance in a fancy shape diamond. Well, that’s only partially true, because the Signature Princess cut diamonds from Brian Gavin are also pretty impressive.

In both instances, these diamonds offer the highest volume of light return in a fancy shape diamond. As a matter of fact, I’m not aware of any other brand that offers this type of consistent performance.

The higher degree of optical precision and a precise set of proportions produces exceptional sparkle factor. Under those circumstances, you’re going to see the kind of mind-blowing, broad-spectrum sparkle that tantalizes the senses.

Antique Cushion Cut Diamonds:

Victor Canera Antique Cushion cut diamond

Victor Canera Antique Cushion Cut Diamond

In the first place, this antique cushion cut diamond by Victor Canera has a unique shape and characteristics. The larger facets are going to produce flashes of light that are larger in size and bolder in appearance.

However, the intensity of the sparkle factor is also going to be different. As a matter of fact, this is a good option if you are looking for a vintage style engagement ring.

In which case, you’ll really like the hand-forged custom jewelry that Victor Canera makes in his studio.

European Ideal Cut Diamonds:

Victor Canera European Round Ideal Cut Diamnond

Victor Canera Ideal European Cut Round

The Canera European round cut diamond on the left is a modern variation of the old European round cut diamond. As a matter of fact, this isn’t really a fancy shape diamond. However, it’s worth checking out if you’re looking for something different.

As you can see the pattern of light return and contrast exhibited this diamond is dramatically different. At the same time, these diamonds produce great light performance. Of course, you should also be aware that the sparkle factor is different from a modern round brilliant cut diamond.

Summary of Diamond Shape:

As you can see, there is more to picking a diamond shape than meets the eye. In the first place, there are all the different facet structures to contend with. And then there is the matter of proportions and the degree of optical precision. At the end of the day, it can be a lot of information to try to digest.

Although this may be true, there really isn’t a reason for you to try and figure all this out on your own. After all, I’ve been in the business for 35+ years in the capacity of a diamond buyer. Under those circumstances, I can help you search for diamonds and pick the best options available. If that sounds good to you, then I invite you to take advantage of our free Diamond Concierge Service.

Super Charge Your Diamond Buying Skills:

Follow the Steps in The Nice Ice® Diamond Buying Blueprint™ and Unlock the Secret for Maximizing Sparkle Factor and Light Performance. These are the Tips & Tricks from the back office of Nice Ice Diamonds.