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Pavilion Main Facets

The pavilion main facets are a crucial component of a diamond’s pavilion, contributing significantly to its overall brilliance, symmetry, and light performance. These facets are positioned on the lower half of the diamond, extending from the culet (the tip at the bottom) to the girdle (the widest part of the diamond). The precise arrangement and number of pavilion main facets influence how light interacts with the diamond, ultimately impacting its sparkle, fire, and overall appearance.

What are Pavilion Main Facets?
The pavilion main facets are the large, kite-shaped facets located on the pavilion of the diamond. These facets extend from the culet (the pointy bottom) to the girdle (the widest perimeter of the diamond).
Typically, round brilliant cut diamonds feature 8 pavilion main facets, while fancy shaped diamonds (such as princess, oval, and cushion) may have a different number of pavilion facets depending on their cut and shape. These facets are key to how the diamond handles light and contributes to its overall aesthetic.
Role of Pavilion Main Facets in Diamond Brilliance
1. Light Reflection and Dispersion
The pavilion main facets are responsible for the internal reflection and refraction of light within the diamond. When light enters the diamond from the table (top flat surface), it interacts with the crown and pavilion facets, causing the light to bounce off the facets and return to the viewer’s eye.
The kite shape of the facets allows for optimal light reflection, enhancing the diamond’s brilliance. Well-designed pavilion facets enable the diamond to exhibit maximum fire, with flashes of light reflecting through the crown.
When these facets are properly proportioned and aligned, they direct light in such a way that the diamond sparkles brilliantly. The facets also contribute to the dispersion of light, creating the colorful flashes that diamonds are famous for.
2. Maximizing Brilliance and Fire
The arrangement of the pavilion main facets is designed to maximize the amount of light that enters the diamond, which is then reflected back through the top facets (the crown). This direct interaction between the pavilion and the crown facets enhances the diamond’s overall brilliance and fire.
In a well-cut diamond, the pavilion main facets work in harmony with the crown facets and the table facet, creating a balance that allows for perfect light performance. This leads to the characteristic sparkle and depth seen in high-quality diamonds.
Properly proportioned pavilion facets allow light to reflect more efficiently, contributing to the vibrant appearance and dazzling visual effect of the diamond.
Effect of Pavilion Main Facets on Diamond Proportions and Symmetry
1. Symmetry and Overall Cut Quality
The symmetry of the pavilion main facets is crucial to achieving a well-proportioned diamond. If the facets are unevenly sized or misaligned, it can disrupt the balance of light reflection and refraction, reducing the diamond’s overall brilliance and fire.
A diamond with well-cut, symmetrical pavilion main facets will have superior light performance, and its sparkle will be uniform across the surface. This contributes to its high cut grade and overall quality.
Asymmetrical or poorly cut pavilion facets will reduce the diamond’s visual appeal, making it less desirable and potentially less valuable.
2. Impact on Diamond’s Shape
The pavilion main facets also contribute to the overall shape and outline of the diamond. In round brilliant diamonds, these facets create the characteristic round shape of the stone when viewed from the top.
In fancy shape diamonds, the pavilion main facets contribute to the unique shape of the diamond, whether it’s a princess, cushion, oval, or emerald cut. The number, shape, and arrangement of pavilion facets vary depending on the diamond shape, but all contribute to the overall visual appeal and proportions.
Pavilion Main Facets and Diamond Value
1. Cut Grade and Light Performance
The quality and symmetry of the pavilion main facets are essential to the cut grade of the diamond. Diamonds with well-cut facets tend to receive higher cut grades, as they exhibit better brilliance, fire, and overall visual appeal.
The cut grade is one of the most important factors in determining a diamond’s value, as it directly impacts the diamond’s aesthetic quality. A diamond with well-aligned pavilion main facets will have higher light performance, making it more desirable to buyers.
2. Aesthetic Appeal
The pavilion main facets are central to the beauty and aesthetic appeal of the diamond. When these facets are correctly cut and aligned, they enhance the diamond’s ability to reflect light, producing vibrant flashes and sparkling effects. This makes the diamond more attractive and valuable in the eyes of buyers.
Understanding Pavilion Main Facet Proportions
1. Ideal Pavilion Depth and Angle
The proportions of the pavilion main facets are closely tied to the pavilion depth and pavilion angle. Properly proportioned facets are critical for achieving optimal light reflection, which is why pavilion depth and pavilion angle are key factors in determining how well the facets will perform.
The ideal pavilion depth percentage typically ranges between 43% to 44% for round brilliant diamonds, and the pavilion angle should generally be between 40.6° and 41.8° for optimal brilliance.
Under-proportioned or over-proportioned pavilion main facets (such as an overly deep pavilion or a shallow pavilion) can cause a reduction in the diamond’s sparkle and can result in undesirable effects like a nailhead or fish eye.
2. Variations in Fancy Cut Diamonds
While round brilliant cut diamonds typically feature 8 pavilion main facets, other diamond shapes have different facet arrangements that are tailored to their unique geometry.
Princess cut diamonds generally have 4 pavilion main facets.
Cushion and radiant cuts feature a combination of pavilion facets that vary in number and shape to match their specific cut characteristics.

The Importance of Pavilion Main Facets
The pavilion main facets are an integral part of a diamond’s cut, and they significantly influence the diamond’s brilliance, fire, and overall appearance. These kite-shaped facets are responsible for reflecting and refracting light within the diamond, contributing to its characteristic sparkle and vibrancy. Properly proportioned and symmetrical pavilion facets result in a diamond that exhibits optimal light performance and has a high-quality appearance.

For diamonds with excellent cut grades, these facets work in harmony with the crown facets and table facet to create a beautiful and eye-catching diamond that is desirable to buyers. Understanding the role of the pavilion main facets and their symmetry, proportions, and alignment is essential when assessing a diamond’s value, quality, and visual appeal.

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Pavilion Depth Percentage

Pavilion Depth Percentage

The pavilion depth percentage is a crucial measurement in understanding how well a diamond performs in terms of brilliance and light reflection. It refers to the pavilion depth (the vertical distance from the girdle to the culet) expressed as a percentage of the diameter of the diamond. This proportional measurement plays a significant role in determining how light interacts with the diamond, and its effect on the diamond’s aesthetic appearance and overall quality.

What is Pavilion Depth Percentage?
Pavilion depth percentage is the ratio of the pavilion depth to the diameter of the diamond, calculated as a percentage.
For example, if the pavilion depth is 43% of the total diameter of the diamond, this means that the pavilion depth makes up 43% of the total horizontal width of the diamond.
The percentage is important because it gives an indication of how well the diamond is proportioned. Proper pavilion depth percentage ensures that the diamond maximizes its light performance and visual appeal, contributing to its brilliance and fire.
How Pavilion Depth Percentage Affects Diamond Light Performance
1. Brilliance and Sparkle
The pavilion depth percentage affects how light is reflected inside the diamond. When light enters the diamond, it bounces off the pavilion facets, refracting and dispersing through the crown (the top part of the diamond) and exiting through the table (the flat top surface).
A well-proportioned pavilion depth percentage ensures that light is optimally reflected and refracted, which maximizes the brilliance and sparkle of the diamond. This is the characteristic that gives a diamond its signature fire and life.
2. Nailhead Effect (Too Deep Pavilion)
When the pavilion depth percentage is too high, the diamond’s pavilion becomes too deep, leading to a phenomenon known as the nailhead.
The nailhead occurs when light is trapped inside the pavilion, failing to reflect out of the diamond’s crown, resulting in a dark appearance. This effect can significantly reduce the diamond’s brilliance and visual appeal.
In other words, a too deep pavilion leads to a lack of light return, causing the diamond to look dull and lacking in sparkle.
3. Fish Eye Effect (Too Shallow Pavilion)
On the flip side, when the pavilion depth percentage is too shallow (i.e., the pavilion is too flat), a fish eye effect can occur.
The fish eye is caused by light entering the diamond and reflecting off the flat pavilion in such a way that it creates an unattractive, dark circle near the center of the diamond. The diamond looks flat and lifeless, with reduced sparkle.
A shallow pavilion prevents light from being properly reflected inside the diamond, causing it to appear less vibrant and lacking in brilliance.
Ideal Pavilion Depth Percentage for Round Brilliant Diamonds
For round brilliant cut diamonds, the ideal pavilion depth percentage typically falls within the range of 43% to 44% of the diamond’s diameter.
This range allows for optimal light reflection and refraction, ensuring the diamond achieves maximum brilliance and fire. Within this range, the diamond will appear vibrant and full of life, with a balanced distribution of light and sparkle.
Impact of Pavilion Depth Percentage on Diamond Value
1. Light Performance and Value
Diamonds with properly proportioned pavilion depth percentages are considered to have higher light performance, which enhances their brilliance and fire. As a result, these diamonds are more valuable and sought after by buyers.
Diamonds with poor pavilion depth percentages (either too deep or too shallow) tend to have lower brilliance and reduced visual appeal, which can decrease their market value.
2. Cut Grade and Market Appeal
The pavilion depth percentage is an integral component of the cut grade of a diamond. A diamond with a well-proportioned pavilion typically receives a higher cut grade, which directly impacts its market price.
Buyers often prioritize diamonds with well-proportioned cuts, as they promise a more aesthetic and eye-catching appearance. As a result, diamonds with the right pavilion depth percentage are more likely to command a premium price in the market.
How to Measure Pavilion Depth Percentage
1. Grading Reports
Reputable gemological laboratories like the Gemological Institute of America (GIA) and the Diamond Certification Laboratory of Australia (DCLA) provide detailed grading reports for diamonds, including the pavilion depth percentage.
These reports include measurements for the pavilion depth, total depth, and diameter of the diamond, which allow buyers and gemologists to calculate the pavilion depth percentage accurately.
2. Manual Measurement
A certified gemologist can also measure the pavilion depth percentage manually using specialized tools like a microscope or digital calipers. However, this measurement is typically included in certified grading reports, ensuring accuracy and consistency.

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Pavilion Depth

The pavilion depth refers to the vertical distance from the girdle (the widest part of the diamond) to the culet (the point at the bottom of the diamond). This dimension plays a crucial role in a diamond’s light performance, brilliance, and overall appearance. The pavilion depth is an essential component of the diamond’s cut proportions, and its proper measurement ensures the stone’s aesthetic appeal and value.

What is Pavilion Depth?
Pavilion Depth is the distance between the girdle (the widest part of the diamond) and the culet (the tip or point at the bottom of the diamond). This measurement can be expressed either in millimeters or as a percentage of the diamond’s total depth (the measurement from the table to the culet).
In the context of diamond cutting, the pavilion depth is a critical parameter because it directly affects how the diamond handles light. If the pavilion depth is improperly proportioned, it can impact the diamond’s brilliance, fire, and overall symmetry.
How Pavilion Depth Affects a Diamond’s Appearance
1. Light Reflection and Brilliance
The pavilion depth plays a key role in how light is reflected inside the diamond. When light enters the diamond from the top (through the table), it is refracted through the crown (the upper portion) and the pavilion before exiting through the top facets.
If the pavilion depth is too shallow, light will pass through the bottom of the diamond without being adequately reflected, resulting in loss of brilliance.
Conversely, if the pavilion depth is too deep, light may reflect too much inside the diamond, and some light may get lost through the sides, reducing the overall brilliance and causing the diamond to appear dark or dull.
2. Fire and Dispersion
The pavilion depth also influences the fire or dispersion of the diamond, which is the ability to break white light into rainbow flashes. A well-proportioned pavilion depth enhances the diamond’s fire, creating colorful flashes of light as the diamond moves.
A shallow pavilion may not allow the diamond to display its full fire potential, and a deep pavilion may cause excessive dispersion, creating a less refined or washed-out appearance.
3. Diamond Proportions and Symmetry
Proper pavilion depth is essential for achieving a well-proportioned diamond. A diamond with balanced proportions will have optimal symmetry, contributing to uniform brilliance and a more aesthetic appearance.
Diamonds with incorrect pavilion depths (either too shallow or too deep) can have imbalanced proportions, leading to uneven sparkle and a less desirable appearance.
Ideal Pavilion Depth for Diamonds
The ideal pavilion depth depends on the shape of the diamond and the overall proportions of the stone. For round brilliant cut diamonds, the pavilion depth is typically measured as a percentage of the total depth (the overall measurement from the table to the culet).

1. Round Brilliant Cut Diamonds
For round brilliant diamonds, the ideal pavilion depth typically falls between 43% and 44% of the total depth of the diamond.
This range ensures the diamond will have the best balance of brilliance and fire, as the pavilion depth will optimize the light reflection and dispersion.
If the pavilion depth is below 43%, the diamond may appear shallow and lack brilliance. If it is above 44%, the diamond may appear too dark or lacking in sparkle.
2. Fancy Shape Diamonds (e.g., Cushion, Princess, Oval)
For diamonds with fancy shapes, the pavilion depth may vary depending on the shape and the overall proportions of the diamond. However, like round diamonds, a well-balanced pavilion depth is essential for optimal light performance.
In general, the ideal pavilion depth for fancy shapes should allow for proper light reflection and brilliance, with variations in pavilion depth based on the individual shape’s design and facet arrangement.
How to Measure Pavilion Depth
1. Using GIA and DCLA Grading Reports
Reputable gemological laboratories like the Gemological Institute of America (GIA) and the Diamond Certification Laboratory of Australia (DCLA) provide detailed cut grades and proportions for diamonds, including the pavilion depth.
The pavilion depth is measured as part of the overall cut proportions and is typically presented as a percentage of the total depth of the diamond. This ensures that buyers are informed about the diamond’s light performance potential.
2. Manual Measurement
A gemologist can manually measure the pavilion depth using precise tools such as a microscope or calipers. However, this measurement is typically included in certified reports from grading organizations like GIA or DCLA, ensuring accuracy and consistency.
Effects of Incorrect Pavilion Depth
1. Too Shallow Pavilion Depth
If the pavilion depth is too shallow (less than 43% for round brilliant diamonds), light will not reflect properly inside the diamond, leading to a loss of brilliance and an overall dull appearance.
Shallow pavilion depths can make the diamond look larger than it actually is, but at the cost of visual performance. The diamond may lack the characteristic sparkle and fire that makes diamonds so captivating.
2. Too Deep Pavilion Depth
If the pavilion depth is too deep (above 44% for round brilliant diamonds), light will be reflected too much inside the diamond and may be lost through the sides. This can lead to a dark appearance and a reduction in the diamond’s brilliance.
Deep pavilion depths can also distort the diamond’s overall proportions, making it appear smaller or less vibrant than it actually is.
Pavilion Depth and Diamond Value
The pavilion depth is a critical factor that influences the cut grade, and therefore, the value of the diamond. Diamonds with properly proportioned pavilion depths tend to have higher brilliance and fire, which makes them more desirable and valuable in the market.

1. Influence on Cut Quality
The cut grade is one of the most important factors in determining a diamond’s overall value. A well-proportioned pavilion depth will result in a higher cut grade, which typically translates to a higher price for the diamond.
Diamonds with poorly proportioned pavilions (either too shallow or too deep) will have a lower cut grade, leading to a decrease in value.
2. Impact on Aesthetic Appeal
Diamonds with properly proportioned pavilion depths have uniform brilliance, sparkle, and fire, making them more visually appealing. As a result, they tend to be more valuable to buyers looking for a high-quality diamond.

The pavilion depth is a critical component of a diamond’s cut proportions and significantly impacts the diamond’s brilliance, fire, and overall visual appeal. The ideal pavilion depth ensures that light is efficiently reflected and refracted within the diamond, maximizing its sparkle and colorful dispersion. Diamonds with properly proportioned pavilion depths tend to be more brilliant, aesthetically pleasing, and valuable. When evaluating a diamond, paying attention to the pavilion depth, along with other key factors like pavilion angle and symmetry, is essential for selecting a high-quality diamond with optimal light performance and beauty.

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Pavilion Angle

The pavilion angle is a key proportion in diamond cutting, referring to the angle between the girdle plane (the widest part of the diamond) and the pavilion main facets (the facets on the lower half of the diamond). This angle plays a crucial role in determining the diamond’s brilliance, sparkle, and overall visual appeal. A well-cut pavilion angle ensures that light entering the diamond is properly reflected and refracted, resulting in the diamond’s characteristic shine and fire.

Understanding Pavilion Angle and Its Impact on the Diamond
1. What is the Pavilion Angle?
The pavilion angle is the angle formed between the girdle plane and the pavilion facets, which are the large, angled facets located beneath the diamond’s girdle.
This angle controls how light is directed through the diamond, impacting how light is reflected and refracted inside the stone before exiting through the crown (the top portion of the diamond).
Why Pavilion Angle is Crucial for Diamond Quality
1. Light Reflection and Brilliance
The pavilion angle directly affects the diamond’s brilliance, which is the amount of white light that is reflected from the diamond’s facets.
If the pavilion angle is too steep (shallow pavilion), light will pass straight through the bottom of the diamond, resulting in poor light reflection and a loss of brilliance.
Conversely, if the pavilion angle is too shallow, light may not be reflected properly inside the diamond, causing the diamond to appear dull and lacking in sparkle.
A well-angled pavilion helps to direct light back through the top of the diamond, enhancing its brilliance and sparkle.
2. Fire and Dispersion
The pavilion angle also influences the diamond’s fire, or the ability to break up white light into its spectral colors (the rainbow flashes that diamonds are known for).
A correct pavilion angle will allow light to be dispersed in a way that maximizes the diamond’s fire and visual impact, making it more vibrant and colorful. A poorly cut pavilion angle may cause the dispersion to be too weak or distorted, resulting in a less dazzling diamond.
3. Symmetry and Aesthetic Appeal
A well-cut pavilion creates a symmetrical diamond where light is evenly reflected and dispersed from all facets.
Proper symmetry helps the diamond to sparkle evenly from all angles, contributing to a uniform brilliance. Poor pavilion angles can lead to uneven reflections, affecting the diamond’s overall visual appeal.
Ideal Pavilion Angle
The ideal pavilion angle varies slightly based on the diamond shape, but for round brilliant diamonds, the generally accepted ideal pavilion angle is between 40.6° and 41.0°. This range allows the diamond to reflect light efficiently and produce the maximum brilliance and fire.

1. Round Brilliant Cut
For round brilliant diamonds, the pavilion angle should ideally be around 40.6° to 41.0°. This range maximizes the diamond’s light return, ensuring the diamond sparkles and reflects light at its best.
If the angle is too steep (over 41.0°), it may cause the diamond to appear dark or dull. If the angle is too shallow (under 40.6°), the diamond may appear washed out, with less light reflection.
2. Other Fancy Cuts
For diamonds with fancy shapes (e.g., emerald, princess, pear, oval), the pavilion angle may vary slightly due to the differences in facet arrangement and proportions. However, the basic principle remains the same: the pavilion angle should be optimized to allow for efficient light reflection and sparkle.
How to Measure the Pavilion Angle
1. GIA and DCLA Grading Reports
Reputable gemological laboratories like the Gemological Institute of America (GIA) and the Diamond Certification Laboratory of Australia (DCLA) provide cut grades that assess a diamond’s proportions, including the pavilion angle.
In a grading report, the pavilion angle will be listed as part of the overall cut quality of the diamond. For example, GIA’s grading system includes a detailed breakdown of the cut grade, which encompasses the pavilion angle, the crown angle, and the overall symmetry of the diamond.
2. Manual Measurement by a Gemologist
A gemologist can manually measure the pavilion angle using precise instruments such as a protractor or optical tools. However, these measurements are typically already included in the official diamond report from grading labs.
Effects of Incorrect Pavilion Angles
1. Too Shallow Pavilion Angle (Low Angle)
If the pavilion angle is too shallow, typically below 40°, light entering the diamond will pass through the bottom of the stone without reflecting back. This results in a loss of brilliance and a flat appearance.
Shallow pavilion angles can also make the diamond look larger than it actually is, but at the cost of visual performance. The diamond may lack the sparkle and fire that buyers typically expect.
2. Too Steep Pavilion Angle (High Angle)
If the pavilion angle is too steep, typically above 41°, the diamond will reflect light poorly, making the diamond look dark and uninteresting.
A steep pavilion angle can cause light to be reflected out of the sides rather than the top of the diamond, which reduces the stone’s overall brilliance and leads to a dead, dark appearance.
3. Symmetry Issues
A poorly cut pavilion may lead to asymmetry, where the facets don’t line up properly. This can cause irregular light reflection, diminishing the diamond’s overall brilliance and sparkle.
How the Pavilion Angle Affects Diamond Value
1. Influence on Cut Quality
The cut grade is one of the most important factors in determining a diamond’s overall value. A well-cut pavilion that optimizes light performance will result in a higher cut grade, which typically translates to a higher value for the diamond.
A poorly proportioned pavilion angle (either too steep or too shallow) can reduce the diamond’s cut grade, making it less valuable in the market.
2. Impact on Aesthetic Appeal
Diamonds with well-cut pavilions tend to be more brilliant and visually stunning, which makes them more desirable to buyers. A diamond with poor pavilion proportions may appear dull, which can lower its perceived value.

The pavilion angle is a key aspect of diamond cutting that directly influences the diamond’s brilliance, fire, and overall aesthetic appeal. The ideal pavilion angle allows light to be reflected efficiently through the diamond, contributing to its signature sparkle and vibrant rainbow flashes. A properly proportioned pavilion angle is crucial for ensuring the diamond’s visual impact and maximizing its value. When evaluating a diamond, paying attention to the pavilion angle and ensuring that it falls within the ideal range is essential for selecting a diamond that is both stunning and valuable.

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Pavilion

The pavilion is the lower portion of a diamond, extending from the girdle (the widest part) of the stone down to the culet (the point at the bottom). It plays a vital role in the diamond’s brilliance and overall visual appeal. The pavilion, along with the crown (the upper portion above the girdle), affects how light interacts with the diamond, influencing its sparkle, fire, and brilliance.

Key Features of the Pavilion
1. Location and Structure
The pavilion lies below the girdle, and is essentially the bottom half of the diamond that is invisible from above when the diamond is set in jewelry.
It extends from the girdle down to the culet, and its angle and depth are key to achieving the right balance of light reflection and brilliance.
2. Pavilion and Light Reflection
The pavilion plays a major role in how the diamond reflects light. When light enters the diamond from the top, it is refracted through the crown, and the pavilion helps to reflect the light back out through the top facets.
If the pavilion is cut too shallow or too deep, it can lead to poor light reflection, resulting in a loss of brilliance. Ideally, the pavilion angle should allow light to be properly refracted and reflected, contributing to the diamond’s overall sparkle.
3. Pavilion Angle and Proportions
The pavilion angle is a critical measurement in diamond cutting. It refers to the angle between the pavilion facets and the girdle. A well-proportioned pavilion will create the ideal light return, while a too shallow or too deep pavilion can cause the diamond to either lose light through the bottom or reflect it poorly.
Ideal Pavilion Angle: Typically, a pavilion angle of about 40.6° to 41.0° is considered ideal for most diamonds, as it creates optimal light performance.
How the Pavilion Affects the Diamond’s Appearance
1. Brilliance and Sparkle
A well-cut pavilion enhances a diamond’s brilliance, or the amount of white light that is reflected from the diamond. The pavilion’s shape and angle help to maximize light return and ensure that the diamond sparkles under various light conditions.
If the pavilion is too shallow, the light passes through the bottom of the diamond and does not get reflected back through the top, reducing the diamond’s brilliance. On the other hand, if the pavilion is too deep, light might reflect too much inside the diamond and fail to return to the eye, leading to a dull appearance.
2. Fire and Dispersion
The pavilion also plays a role in the diamond’s fire, or the dispersion of light into rainbow-colored flashes. A well-cut pavilion will help to disperse the light, creating a more vibrant, colorful display.
The depth and angle of the pavilion contribute to how well the diamond can display its fire.
3. Symmetry and Proportions
The symmetry of the pavilion is just as important as its angle. If the pavilion is not symmetrical, it can cause light to be unevenly distributed throughout the diamond, leading to a lack of balance in the diamond’s brilliance.
Properly proportioned pavilion facets should be symmetrical and aligned to ensure optimal light reflection and a uniform sparkle.
Pavilion and Diamond Shapes
While the pavilion is a significant feature in all diamond shapes, its structure and appearance can vary depending on the cut style of the diamond.

1. Round Brilliant Cut
In a round brilliant diamond, the pavilion is cut into 58 facets, contributing to its ideal brilliance and sparkle. The pavilion in round cuts is designed to reflect light in the most efficient manner, maximizing the diamond’s sparkle.
2. Princess Cut
The pavilion of a princess cut diamond is typically square or rectangular. Like other cuts, its angle plays an important role in how light interacts with the diamond.
A well-cut princess diamond will have a pavilion that allows for maximum light reflection, contributing to its signature brilliance.
3. Emerald Cut
Emerald cut diamonds have a step-cut pavilion, which is a series of rectangular facets that create a distinctive, hall-of-mirrors effect. This type of pavilion results in less brilliance compared to round cuts but highlights the diamond’s clarity and color.
4. Other Fancy Cuts
The pavilion in fancy shapes (e.g., oval, cushion, pear) is designed to complement the overall symmetry and proportions of the diamond. Each shape will have a pavilion with a unique cut style that maximizes the diamond’s light return and visual appeal.
Pavilion and Diamond Value
The quality of the pavilion is crucial for determining a diamond’s overall value and appearance. A poorly cut pavilion (too shallow or too deep) can reduce the diamond’s brilliance and sparkle, which in turn can decrease its market value.

1. Cutting Quality
The cut grade of a diamond is influenced by how well the pavilion is proportioned. A diamond with a well-cut pavilion will receive a higher cut grade, which can increase its overall value.
2. Impact on Durability
A well-cut pavilion also ensures that the diamond is structurally sound, reducing the risk of damage. If the pavilion is too shallow or deep, it can make the diamond more vulnerable to chipping or fractures. Proper proportions ensure that the diamond remains durable and suitable for daily wear.
How to Evaluate the Pavilion
When evaluating a diamond, paying attention to the pavilion angle and symmetry is crucial for ensuring that the diamond will perform well in terms of brilliance, fire, and overall visual appeal. Here are some things to consider when assessing a diamond’s pavilion:

1. Check the Pavilion Angle
A well-cut pavilion will typically have an angle between 40.6° and 41.0° for most round brilliant diamonds.
If the angle is too steep or too shallow, it can affect the diamond’s brilliance.
2. Inspect the Symmetry
Ensure that the pavilion is symmetrical to avoid any uneven light distribution. Gemological grading reports from organizations like the GIA and DCLA often assess symmetry and cut proportions, which can help you evaluate the diamond’s pavilion.
3. Look at the Diamond in Different Lighting
To fully appreciate the pavilion’s effect on the diamond’s sparkle, view the stone under natural light and artificial lighting. A well-proportioned pavilion should enhance the diamond’s sparkle and brilliance under both conditions.

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Overblue

strong blue under long wave ultraviolet light

The Effect of Strong Blue Fluorescence in Diamonds
The term “Overblue” refers to a diamond that exhibits strong blue fluorescence when exposed to long-wave ultraviolet (UV) light. This phenomenon occurs when the diamond absorbs UV light and emits a visible blue glow. While fluorescence in diamonds can be a natural and even desirable trait in some cases, an overblue diamond refers specifically to stones with extremely strong blue fluorescence, which can sometimes negatively impact their appearance.

Understanding Fluorescence in Diamonds
1. What is Fluorescence?
Fluorescence in diamonds is a natural occurrence that happens when a diamond absorbs ultraviolet light and then re-emits it as visible light, typically as a blue glow. Not all diamonds exhibit fluorescence, and its intensity can vary from none to very strong. Fluorescence is often graded on a scale from none to very strong, with the most common colors being blue (the most desirable) or less frequently yellow and green.

2. Types of Fluorescence
None: No fluorescence; the diamond remains unchanged under UV light.
Faint to Medium: Noticeable fluorescence, but usually doesn’t significantly impact the diamond’s appearance under normal lighting.
Strong to Very Strong: A bright, noticeable glow, which may be more obvious under UV light or in low-light conditions. In the case of overblue diamonds, this fluorescence is very intense and can affect the diamond’s overall appearance.
What Makes a Diamond Overblue?
An overblue diamond refers to a diamond with extremely strong blue fluorescence. This can result in a distinctive blue glow that may be evident under long-wave UV light or sometimes even in regular daylight. While fluorescence can enhance the diamond’s appearance in certain conditions, an overblue diamond can present issues for the stone’s overall aesthetic and value.

Issues with Overblue Diamonds
1. Oily or Milky Appearance in Daylight
Diamonds with strong fluorescence can appear cloudy, oily, or milky under normal daylight or incandescent lighting, which can affect their brilliance. This happens because the fluorescence can cause the diamond to scatter light unevenly, diminishing its overall sparkle.
High-color diamonds (D-F grades) with strong fluorescence are often the most affected, as their lack of color accentuates the milky or oily appearance.
2. Misleading Perception of Superior Colour
In the past, the term “overblue” was sometimes used to suggest that a diamond with strong blue fluorescence had a superior color grade, leading to confusion in the market. Some buyers believed that a strong blue fluorescence was an indicator of a higher-quality diamond.
However, fluorescence does not directly correlate with the color grade of a diamond, and a diamond’s appearance under normal lighting is far more important in assessing its true beauty.
3. Impact on Diamond Value
While some buyers find fluorescence attractive, an overblue diamond can decrease the diamond’s market value. This is because it affects the overall visual quality, particularly if the stone appears cloudy or oily under natural light.
Diamonds with extremely strong fluorescence can also be perceived as less desirable due to the unpredictable visual effects they may exhibit in different lighting environments.
Should You Avoid an Overblue Diamond?
Whether or not to buy an overblue diamond depends on your personal preferences and how the diamond appears to you in real-world lighting.

Reasons to Avoid an Overblue Diamond
Aesthetic Concerns: The milky or oily look that can appear under normal lighting may not appeal to everyone, especially those seeking a diamond with the highest possible brilliance and clarity.
Reduced Value: Overblue diamonds may be worth less in the market compared to their counterparts with less noticeable fluorescence.
Reasons to Consider an Overblue Diamond
Personal Preference: Some people enjoy the blue glow that fluorescence provides, especially under UV light.
Price: Due to the perceived lower value, diamonds with strong fluorescence may be available at a lower price, which could appeal to those on a budget.
How to Detect Overblue Fluorescence
If you’re interested in purchasing a diamond, it’s essential to check the fluorescence grading and assess how it might affect the diamond’s appearance.

1. Check the Diamond’s Certification
Reputable gemological laboratories like GIA, DCLA, and AGS will include a fluorescence grade on the diamond’s certificate. If the diamond is marked as strong blue or very strong blue, it may exhibit the overblue effect.

2. View the Diamond in Different Lighting
It’s essential to examine the diamond in natural light to see if the overblue fluorescence makes it appear cloudy or oily.
Examine the diamond under UV light to observe the fluorescence intensity and its effect on the stone’s visual appeal.
3. Personal Preference
Ultimately, whether to choose a diamond with strong fluorescence, including overblue, depends on your personal taste and the diamond’s appearance in various lighting conditions. If you are unsure, you may want to consult a gemologist or diamond expert to better understand how fluorescence will affect the look and value of the diamond.

Overblue diamonds exhibit extremely strong blue fluorescence, which can result in a distinct blue glow under UV light. In the past, the term was used misleadingly to suggest that the diamond had a superior color, but it can actually cause the diamond to appear milky or oily in normal daylight, especially for high-color diamonds. Fluorescence in diamonds is a natural phenomenon, but when it is too strong, it can detract from the diamond’s beauty. Whether you should buy an overblue diamond depends on your personal preference for the glow and how it looks in natural light. Be sure to check the fluorescence grading and view the diamond in different lighting before making a purchase decision.

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Oval Cut

Oval shaped diamond

Features of an Oval Cut Diamond
1. Elongated Shape
The oval cut is an elongated shape that can range from a perfect oval to a more elongated ellipse depending on the ratio of length to width.
Proportions can vary, but a ratio of approximately 1.33 to 1.66 (length-to-width) is typically considered ideal for maintaining a graceful appearance.
2. Brilliant Cut Facets
Like the round brilliant cut, the oval cut diamond features 58 facets arranged in a brilliant cut style.
These facets are designed to maximize light reflection and create a stunning, fiery sparkle. The brilliance is typically comparable to that of round diamonds, though the oval shape tends to have a slightly softer light return due to the shape’s rounded edges.
3. Soft, Rounded Edges
Oval diamonds are characterized by their soft, rounded edges, making them less prone to visible chipping compared to shapes with sharp corners, such as the emerald cut or princess cut.
4. Larger Surface Area
The oval cut tends to appear larger than a round diamond of the same carat weight due to its elongated shape, offering more visual size, which is often appealing to those who prefer a larger stone without sacrificing carat weight.
5. Symmetry and Bowtie Effect
An important feature to check in an oval diamond is its symmetry. The diamond should have a balanced outline without any noticeable bulges or flat areas.
Many oval diamonds can exhibit a bowtie effect, where the center of the diamond appears darker, resembling the shape of a bowtie. While not a flaw, a noticeable bowtie can sometimes be distracting, so it’s important to select a stone with minimal or no bowtie effect.
Why Choose an Oval Cut Diamond?
1. Timeless Elegance with a Modern Twist
The oval cut has become increasingly popular due to its elegant, vintage charm, combined with a modern appearance. It offers the classic appeal of a round diamond but with a more distinctive and elongated look that feels fresh and different.
2. Appears Larger Than Other Shapes
Due to its elongated shape, an oval diamond can look larger than round diamonds of the same carat weight, offering more presence without the need to increase carat weight. This is especially appealing for those who want the look of a larger diamond at a more affordable price.
3. Versatility in Setting Styles
Oval cut diamonds pair well with various types of settings, including solitaire, halo, three-stone, and pavé bands. Their elongated shape can also flatter longer fingers, making them a popular choice for engagement rings.
The oval shape works well in both modern, minimalist settings and vintage-inspired designs, making it a versatile choice for any style preference.
4. Less Prone to Chipping
Since oval diamonds have no sharp corners like princess or emerald cuts, they are less susceptible to chipping or damage, making them a durable and practical choice for everyday wear, especially for engagement rings.
How to Choose the Perfect Oval Cut Diamond
1. Pay Attention to Proportions
Proportions are key when selecting an oval cut diamond. Look for a diamond with balanced length-to-width ratios (1.33 to 1.66) for a more elegant and symmetrical appearance.
Symmetry is also important to ensure the diamond’s facets align perfectly and create the desired visual appeal.
2. Check for the Bowtie Effect
The bowtie effect is a common characteristic of oval diamonds, but you may want to choose one with a minimal bowtie for better visual appeal. A pronounced bowtie can detract from the overall brilliance of the diamond.
3. Focus on the Cut Quality
The cut quality of an oval diamond significantly impacts its brilliance and sparkle. Ensure that the diamond has been cut to the highest standards, with well-executed facets that maximize light return. A well-cut oval will give the diamond brilliant sparkle similar to a round brilliant.
4. Opt for a Quality Certification
Choose a diamond with a certification from a reputable gemological laboratory, such as GIA, DCLA, or AGS. Certification ensures the diamond’s quality and gives you a detailed report on its cut, color, clarity, and carat weight.
Oval Cut vs. Other Diamond Shapes
Shape Unique Feature Brilliance Popular Setting Style
Oval Cut Elongated shape, large surface area Similar to round brilliance Solitaire, Halo, Three-Stone
Round Brilliant Perfectly symmetrical, circular Maximum brilliance Solitaire, Pavé, Halo
Cushion Cut Rounded corners, soft sparkle Moderate brilliance Halo, Vintage-Inspired, Solitaires
Princess Cut Square shape with sharp corners High brilliance, sharp sparkle Modern Solitaire, Three-Stone
Emerald Cut Step-cut with large, flat facets Subtle sparkle, elegant shine Solitaire, Vintage-Inspired

The Oval Cut diamond is a stunning choice for those who seek an elegant, elongated shape with exceptional brilliance. Combining the fire and brilliance of the round brilliant cut with a unique and flattering shape, it is a versatile option for various jewelry settings. The larger surface area and soft edges offer a distinctive look while being less prone to chipping. Whether you prefer a modern, minimalist design or a vintage-inspired setting, the oval cut is a timeless option that is sure to stand out.

 

 

 

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Old Mine Cut

The Old Mine Cut is a historical diamond cut, first popularized in the 18th and 19th centuries. It is an early version of the modern cushion cut, characterized by its deep pavilion, high crown, small table, and large culet. These diamonds were hand-cut by artisans, making each one unique, with a softer, romantic appeal compared to today’s precision-cut stones.

Key Features of an Old Mine Cut Diamond
1. Cushion-Like Shape
The Old Mine Cut has a rounded-square or cushion-like outline, often with slightly asymmetrical edges due to hand-cutting techniques.
2. Deep Pavilion & High Crown
A deep pavilion (bottom part of the diamond) gives the stone a noticeable depth, which was designed to enhance light reflection in candlelight.
The high crown (upper portion of the diamond) contributes to its distinctive, antique look.
3. Small Table & Large Culet
The table (flat top facet) is relatively small, which contrasts with modern cuts that have larger tables to maximize brilliance.
The culet (bottom facet) is large and visible from the top, creating a soft reflection within the diamond instead of the sharp brilliance seen in modern cuts.
4. Fewer, Larger Facets
Typically features 58 facets, but they are larger and chunkier compared to modern brilliant-cut diamonds, producing a softer, less fiery sparkle.
5. Hand-Faceted & Slightly Asymmetrical
Old Mine Cuts were hand-faceted without modern precision technology, often leading to slight variations in shape and symmetry.
History of the Old Mine Cut
Originated in the late 17th to early 18th century and became the dominant diamond cut of the Georgian and Victorian eras.
Named “Old Mine Cut” because many of these diamonds came from old mines in Brazil and India, before major diamond discoveries in Africa.
With the invention of more advanced cutting tools, the Old European Cut (a rounder, more symmetrical version) evolved from the Old Mine Cut in the late 19th century.
How Old Mine Cut Diamonds Compare to Modern Cuts
Feature Old Mine Cut Modern Cushion Cut Round Brilliant Cut
Shape Cushion-like, slightly irregular Cushion-like, precise symmetry Perfectly round
Facets Large, chunky facets Smaller, precision-cut facets Tiny, uniform facets
Table Small Medium Large
Culet Large, visible Small or non-existent Very small or none
Brilliance Soft glow, optimized for candlelight Bright and fiery brilliance Maximum brilliance
Cutting Method Hand-faceted Machine-faceted Machine-faceted
Why Choose an Old Mine Cut Diamond?
1. Vintage & Unique Charm
Ideal for antique-style engagement rings or heirloom jewelry.
No two Old Mine Cut diamonds are exactly alike, adding to their individuality.
2. Warmer, Romantic Glow
Their soft sparkle creates a more romantic, vintage feel, different from the sharp brilliance of modern cuts.
3. Ethical & Sustainable Choice
Since many Old Mine Cut diamonds are reclaimed or antique stones, they offer a more environmentally friendly and ethical alternative to newly mined diamonds.
4. Great for Those Who Love History
Owning an Old Mine Cut diamond means having a piece of history from the Georgian, Victorian, or Edwardian era.

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Off-Make

Trade term for a diamond that has been badly polished or finished.

The term “off-make” is a trade term used to describe a diamond that has been poorly cut, polished, or finished, resulting in flaws in its overall make. This means the diamond does not meet ideal proportions, symmetry, or polish standards, leading to reduced brilliance, fire, and overall aesthetic appeal.

Characteristics of an Off-Make Diamond
A diamond is considered off-make when it exhibits one or more of the following defects:

1. Poor Proportions
Too deep or too shallow – Affects light reflection and reduces brilliance.
Mismatched angles – Poor crown and pavilion angles lead to light leakage.
Uneven girdle thickness – Some areas may be too thick (wasting carat weight) or too thin (making the diamond vulnerable to chipping).
2. Weak Symmetry
Misaligned facets – When facets are uneven or not placed correctly, the diamond lacks balance.
Table and culet off-center – Affects the diamond’s optical performance and sparkle.
3. Low-Quality Polish
Visible polish lines or marks – Can create a dull appearance.
Rough or grainy surface texture – Reduces light reflection and brilliance.
4. Light Performance Issues
Nailhead effect – The center appears dark due to excessive depth.
Fish-eye effect – A distorted reflection of the girdle inside the table, caused by a shallow pavilion.
Windowing – When light passes straight through the diamond rather than reflecting back, making it appear see-through.
How Off-Make Affects a Diamond’s Value
1. Lower Market Demand
Off-make diamonds are considered less desirable by both jewelers and consumers because they lack brilliance and symmetry.

2. Reduced Sparkle & Fire
A well-cut diamond maximizes brilliance (white light reflection) and fire (color dispersion).
Off-make diamonds often appear lifeless, dull, or dark, even with good clarity and color.
3. Lower Resale & Appraisal Value
Since cut is the most important factor in a diamond’s beauty, a poorly made diamond will be valued lower than a well-cut stone of the same carat weight, clarity, and color.
4. Potential for Weight Retention Over Beauty
Some off-make diamonds are intentionally cut poorly to retain more carat weight from the rough, sacrificing quality for size.
How to Avoid Buying an Off-Make Diamond
1. Check the Cut Grade
Buy diamonds certified by DCLA, GIA, or AGS, which provide cut grades ranging from Excellent to Poor. Avoid stones with Fair or Poor cut grades.
2. Inspect Light Performance
Look at the diamond under different lighting conditions to check for dark areas, weak reflections, or excessive transparency.
3. Look for Proportion Guidelines
Ideal Table Size: 53-58% of the total width
Ideal Depth Percentage: 58-63%
Crown and Pavilion Angles: Well-balanced for optimal light return
4. Use a Loupe or Microscope
Check for symmetry, facet alignment, and polish marks.
5. Ask for an ASET or Ideal Scope Image
These tools reveal light leakage, helping determine if the diamond is well-cut.

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Octahedron

Rough diamond Octahedron

An octahedron is one of the most sought-after crystal shapes for rough diamonds, featuring eight triangular faces arranged symmetrically. This shape resembles two four-sided pyramids joined at their base, forming a perfect geometric structure. Due to its natural symmetry and efficient cutting potential, octahedral rough diamonds are highly desirable for diamond cutting and manufacturing.

Characteristics of an Octahedral Diamond
Crystal Structure: Composed of eight equilateral triangular faces
Formation: Forms naturally under high pressure and heat within the Earth’s mantle
Symmetry: Well-balanced, making it one of the most efficiently cuttable rough diamond shapes
Occurrence: One of the most common and valuable rough diamond shapes found in nature
Why Octahedral Rough Diamonds Are Coveted
1. Ideal for Cutting Round Brilliant Diamonds
The octahedral shape is perfectly suited for cutting two round brilliant diamonds from a single rough stone, maximizing yield and minimizing waste.
Diamond cutters often cleave or saw the rough along its natural planes to create two symmetrical, high-quality diamonds.
2. Natural Growth of Diamonds
The octahedron reflects the cubic crystal system of diamonds, where atoms arrange themselves in the most stable geometric form.
Over millions to billions of years, carbon atoms bond in this shape under extreme pressure deep within the Earth.
3. High Clarity Potential
Since octahedral diamonds grow in a stable environment, they often develop with fewer inclusions compared to irregularly shaped rough stones.
Their internal structure is generally strong, reducing the risk of fractures during the cutting process.
Octahedral Diamonds in Cutting & Polishing
How Cutters Assess an Octahedral Rough Diamond:
Orientation: Experts determine the best way to cut the rough to achieve the highest carat yield.
Inclusion Mapping: If internal flaws are present, cutters adjust the cutting plan to eliminate or minimize them.
Cleaving/Sawing: The rough is often split along its natural grain to form two high-quality gemstones.
Common Diamond Cuts from an Octahedron:
Cut Style Why It’s Chosen for Octahedral Rough
Round Brilliant Uses the natural symmetry of the octahedron to produce two symmetrical stones
Princess Cut Retains a high percentage of the original rough weight
Cushion Cut Maximizes brilliance while preserving rough material
Octahedron vs. Other Rough Diamond Shapes
Rough Diamond Shape Description Cutting Potential
Octahedron Eight triangular faces, symmetrical High yield, excellent for round brilliants
Dodecahedron Twelve pentagonal faces, irregular More cutting challenges, lower yield
Macles (Twinned Crystals) Flattened, triangular shape due to twinning Often used for fancy cuts, less efficient for rounds
Cubo-octahedron Mix of cube and octahedron faces Good for step cuts like emerald or Asscher


The octahedron is the most desirable natural shape for rough diamonds due to its symmetry, high clarity potential, and efficient cutting yield. This structure allows diamond cutters to maximize the rough’s potential, often yielding two high-quality round brilliant diamonds from a single octahedral crystal. Its formation represents the natural stability of diamond growth, making it a prized find in the world of gemology.