Admin DCLA – Page 7 – The Diamond Certification Laboratory of Australia (DCLA)

July, 2017February, 2025

Marquise Cut

The marquise cut is a diamond shape that is elongated and features two pointed ends, creating an elegant, oval-like shape. This cut is named after the Marquise de Pompadour, the mistress of King Louis XV of France, who is said to have commissioned a diamond in this shape to resemble the smile of the Marquise. The shape is often associated with royalty and sophistication, as it combines beauty with a sense of regal charm.

Also known as a navette (which is the French term for “little boat”), the marquise cut’s design is reminiscent of a boat’s hull, with its long, sweeping lines and pointed ends. This cut is distinctive and versatile, often used in rings, earrings, and necklaces to create a striking and elongated visual effect.

Characteristics of a Marquise Cut
Shape and Proportions:

The marquise cut is an elongated oval with pointed tips at both ends, giving it a symmetrical and graceful appearance. The length-to-width ratio can vary, but it is typically quite long and narrow, which enhances the illusion of a larger size.
The length of the diamond can range from about 1.5 to 2.5 times its width, and the exact ratio depends on the preference of the buyer or the designer. A diamond with a more elongated shape will often appear larger than a round diamond of the same carat weight.
Brilliance and Sparkle:

The marquise cut is designed to maximise the diamond’s brilliance, meaning it reflects a high degree of light, resulting in an eye-catching, sparkly appearance. This is due to the number of facets that are carefully aligned to reflect light in the optimal manner.
The elongated shape enhances the visual size of the diamond, making it look larger than a round brilliant cut of the same weight. It also offers the added benefit of a larger surface area to show off the diamond’s brilliance.
Facets and Cut:

The marquise cut is usually faceted similarly to a round brilliant diamond, with 58 facets that maximise light reflection. The crown of the diamond, or the top part, has a series of triangular and kite-shaped facets, which work together to create the sparkle.
Due to the pointed ends, it is important for the cutter to ensure that these areas are not too sharp, as they can make the diamond more susceptible to damage. The cutting process focuses on maintaining the integrity of the shape and ensuring that the facets are aligned to produce the maximum brilliance and fire.
Unique Design and Versatility:

The marquise cut’s distinctive elongated form makes it a popular choice for engagement rings, especially when the goal is to make the diamond appear larger. Its shape is particularly flattering for smaller fingers, as it creates the illusion of length and elegance.
The marquise cut is also versatile in its use in jewellery design, as it pairs well with both traditional and modern settings. It can be used in rings, pendants, earrings, and bracelets, and it is often surrounded by other diamonds or gemstones to enhance its overall appearance.
Visual Appeal:

The elongated silhouette of a marquise cut diamond offers a slimming effect on the finger or the wearer’s appearance, making it a popular choice for those who want to emphasise elegance and sophistication. The cut also provides optical illusions, making the stone appear larger and more slender.
The pointed ends, in particular, create a dramatic and bold look, making marquise diamonds stand out in jewellery pieces. This cut is often chosen by those who want a distinctive, eye-catching piece that is unique and memorable.
Considerations When Choosing a Marquise Cut
Proportions and Symmetry:

When selecting a marquise cut diamond, the proportions and symmetry of the shape are essential. An asymmetrical or improperly proportioned marquise cut can result in a less desirable appearance. For example, a diamond that is too elongated or too broad might not offer the same balance and beauty as one with ideal proportions.
Symmetry is particularly important with the marquise cut, as uneven points or misaligned facets can detract from the overall sparkle and visual appeal.
Length-to-Width Ratio:

As mentioned, the length-to-width ratio is a key consideration for a marquise cut diamond. A ratio that is too extreme (e.g., overly long and narrow) may appear out of proportion, while a more balanced ratio (typically around 1.5 to 2.0) will provide a more harmonious and aesthetically pleasing appearance.
Pointed Ends:

The pointed ends of the marquise cut are vulnerable to damage, such as chipping, if the diamond is not set properly or if it is subjected to physical stress. For this reason, many buyers opt for a protective setting that shields the points. A bezel setting or a setting with raised prongs can help protect these vulnerable areas.
Clarity Considerations:

The clarity of a marquise cut diamond is particularly important because inclusions that appear near the pointed ends can be more noticeable due to the way light interacts with the shape. When purchasing a marquise cut diamond, it’s wise to choose one with minimal inclusions near the tips, as these can be more visible and detract from the diamond’s brilliance.
Popularity and History of the Marquise Cut
The marquise cut has remained a popular choice for engagement rings and jewellery designs for centuries. Its timeless appeal is linked to its association with royalty, particularly after it was named after the French Marquise de Pompadour. The shape has been embraced in various forms of luxury jewellery, and its sleek, sophisticated design continues to attract those seeking a distinctive, elegant piece.

The marquise cut is also a symbol of individuality, offering a unique alternative to traditional round brilliant or cushion-cut diamonds. It provides an option for those who want a ring or piece of jewellery that stands out, while still showcasing the brilliant qualities of the diamond.

July, 2017February, 2025

Make

The diamond make refers to the overall quality of the cut of a diamond, evaluating how well it has been shaped and finished. This includes an assessment of the proportions, symmetry, and polish of the diamond, all of which contribute to its brilliance, fire, and scintillation (the sparkle of the diamond). The make plays a crucial role in determining the diamond’s visual appeal and its overall value. A well-cut diamond will exhibit optimal light performance, making it appear vibrant and full of life.

Key Aspects of Diamond Make
Proportions:

The proportions of a diamond are crucial to its overall make. This refers to the specific dimensions of the diamond, including the depth, table, crown angle, pavilion angle, and the girdle. The proportions must be balanced in such a way that they allow for the ideal reflection and refraction of light, maximising the diamond’s brilliance.
Ideal Proportions: For a round brilliant cut diamond, the ideal proportions ensure that light entering the diamond is properly reflected and refracted, bouncing around the facets before exiting through the crown and creating sparkle.
Poor Proportions: A diamond with poor proportions will either leak light out from the bottom (leading to a dark, dull appearance) or fail to reflect light properly (causing a lifeless look).
Symmetry:

Symmetry refers to the precision and alignment of the facets in a diamond. A well-symmetrical diamond ensures that each facet is positioned correctly to reflect light at the right angles. For round brilliant cuts, symmetry affects how well the facets align to create the signature sparkle. Any asymmetry, such as off-centre facets or mismatched angles, will interfere with the flow of light and negatively impact the diamond’s overall performance.
Ideal Symmetry: A diamond with excellent symmetry will display uniformity across all facets, contributing to a balanced distribution of light and a consistent sparkle.
Poor Symmetry: A diamond with poor symmetry may display uneven facets, which can affect the visual appearance and reduce its brilliance.
Polish:

Polish refers to the smoothness and finish of the diamond’s surfaces, including the crown, pavilion, and girdle. A well-polished diamond allows light to pass through smoothly, enhancing its brilliance and preventing light from being blocked by rough or uneven surfaces.
Ideal Polish: Diamonds with excellent polish will have a smooth, flawless surface that reflects light optimally. There will be no visible abrasions, scratches, or imperfections on the surface.
Poor Polish: If the diamond is poorly polished, the surface may have visible blemishes, which can distort the light and detract from the diamond’s overall sparkle.
Cut Grade:

The cut grade is a composite evaluation that includes the proportions, symmetry, and polish of the diamond. Diamond grading laboratories, such as the Gemological Institute of America (GIA), assign cut grades that range from Excellent to Poor based on these factors. A diamond with an excellent cut will showcase ideal proportions, symmetry, and polish, leading to superior brilliance and fire.
Ideal Cut: A diamond with an ideal cut is precisely shaped to reflect light in the most efficient way, maximising its brilliance and visual appeal.
Good/Very Good Cut: These diamonds may have minor deviations from ideal proportions or symmetry, but they still exhibit strong light performance.
Fair/Poor Cut: These diamonds have significant deviations from the ideal, which can lead to dull or lifeless appearances.
Impact of Diamond Make on Light Performance
The make of a diamond directly influences how light is handled by the stone. When light enters a diamond, it travels through the crown and pavilion before exiting, either through the top (creating brilliance) or dispersing into a spectrum of colours (creating fire). The cut quality determines how well this light is managed and returned to the observer’s eye.

Brilliance:

A diamond’s brilliance is the amount of white light it reflects. A well-cut diamond with excellent proportions and symmetry will reflect light efficiently, leading to a bright and lively appearance.
Fire:

Fire refers to the dispersion of light into a spectrum of colours, similar to a rainbow. Diamonds with an excellent make will show vibrant flashes of colour, enhancing the overall beauty and desirability of the stone.
Scintillation:

Scintillation refers to the flashes of light seen when the diamond moves. A well-cut diamond will exhibit a high degree of scintillation, making it appear sparkling and dynamic as it shifts in the light.
Importance of Diamond Make in Valuation
The make of a diamond significantly affects its value. Diamonds with excellent makes are highly sought after and are often priced higher because they exhibit superior light performance and visual appeal. In contrast, diamonds with poor makes may be priced lower due to their less-than-optimal appearance.

High-Quality Make: Diamonds with excellent cuts, symmetry, and polish will be more valuable due to their superior brilliance, fire, and scintillation. These diamonds are also more desirable to consumers, who often seek the most visually stunning stones.

Low-Quality Make: Diamonds with poor cuts, imbalanced proportions, or visible imperfections on the surface will likely be less valuable. These diamonds do not reflect light as efficiently, resulting in a duller appearance and lower demand in the market.

July, 2017February, 2025

Lower-Girdle Facets

The lower-girdle facets are crucial elements in the overall symmetry and brilliance of a diamond. These triangle-shaped facets are located on the pavilion of the diamond, directly adjacent to the girdle, which is the outer edge of the diamond. The pavilion refers to the bottom part of the diamond, below the girdle, which is responsible for reflecting light back through the crown and into the observer’s eye.

Position and Structure
Location: The lower-girdle facets are positioned on the pavilion of the diamond, near the girdle. They are situated just below the main facets of the pavilion, including the main pavilion facets, which are the large, flat surfaces that reflect light into the crown.

Shape: These facets are typically triangle-shaped, although their size and exact proportions can vary depending on the cut of the diamond. In some diamonds, these lower-girdle facets may be slightly elongated or modified, but they usually maintain a triangular form.

Function: The primary function of the lower-girdle facets is to help direct light in the diamond, contributing to its brilliance and scintillation. These facets work by reflecting light that enters the pavilion from below, which then bounces back through the crown of the diamond, creating the visual effects that make diamonds sparkle. The interaction between the light and these facets is essential in maximizing the diamond’s overall visual appeal.

Impact on Diamond Performance
Brilliance:

The brilliance of a diamond is its ability to reflect white light. The lower-girdle facets play an important role in this by directing light from the pavilion back into the crown. When the light is properly reflected, it bounces back to the viewer’s eye, enhancing the diamond’s brightness.
Scintillation:

Scintillation refers to the flashes of light that occur when a diamond moves or is viewed from different angles. The lower-girdle facets help enhance scintillation by creating additional reflections and refractions of light. Their triangular shape and position allow them to catch light from various angles, contributing to the diamond’s overall sparkle.
Symmetry:

Properly aligned and symmetrical lower-girdle facets are essential to the overall symmetry of the diamond. When the facets are evenly proportioned, the diamond will have a more visually appealing appearance, with well-defined light reflections and a balanced sparkle. Any irregularities in the alignment or shape of these facets can lead to an uneven distribution of light, reducing the diamond’s brilliance.
Grading the Lower-Girdle Facets
In diamond grading, the quality of the lower-girdle facets is considered as part of the overall cut grade, which evaluates how well the diamond has been shaped and proportioned to maximize its brilliance, fire, and scintillation. Some of the factors that affect the grading of the lower-girdle facets include:

Size and Proportion:

The size and proportion of the lower-girdle facets should be well balanced with the other facets of the diamond, including the main pavilion facets and the upper girdle facets. Proper proportions contribute to the diamond’s overall symmetry and visual appeal.
Symmetry:

Symmetry is one of the key components of diamond grading. Lower-girdle facets should be symmetrical, with uniform size and placement. Any misalignment or uneven facet sizes can disrupt the flow of light through the diamond and impact its overall performance.
Polish:

A well-polished surface on the lower-girdle facets enhances the diamond’s ability to reflect light. Poor polishing can lead to a dull appearance and reduce the brilliance of the diamond.
Role in Different Diamond Cuts
While lower-girdle facets are typically found in round brilliant cut diamonds, their placement and function can also be seen in other shapes that share similar cutting structures. However, the round brilliant cut diamond relies most heavily on the lower-girdle facets to achieve optimal light performance.

Round Brilliant Cut:

In the round brilliant cut, the lower-girdle facets are particularly important in creating the characteristic sparkle and fire that this cut is known for. The precise arrangement of these facets ensures that the diamond exhibits maximum brilliance and scintillation.
Other Fancy Cuts:

While fancy shapes like emerald, princess, or asscher cuts have different facet structures, they still rely on the principles of light reflection and refraction that are found in the lower-girdle facets of the round brilliant cut. For these shapes, the positioning and number of lower-girdle facets can vary, but their purpose remains the same: to enhance the diamond’s brilliance.
Impact of the Lower-Girdle Facets on Diamond Value
Diamonds with well-proportioned and well-cut lower-girdle facets typically have better light performance, meaning they will display more brilliance, scintillation, and fire. As such, diamonds with ideal or well-graded lower-girdle facets are generally considered more valuable because they are more visually appealing. Poorly proportioned or poorly cut lower-girdle facets can negatively affect the diamond’s performance, reducing its overall desirability and value.

July, 2017February, 2025

Loupe

A diamond loupe is a small, handheld magnifying lens that is an essential tool for examining diamonds, especially when it comes to evaluating their clarity. It allows gemologists, jewellers, and buyers to inspect the intricate details of a diamond, helping to identify inclusions, blemishes, and other microscopic characteristics that affect its overall quality.

Key Features of a Diamond Loupe
Magnification Power:

The most common magnification used for grading diamonds is 10x magnification. This level of magnification is optimal for examining the intricate details of a diamond without causing strain on the eyes or distorting the image.
While 10x magnification is standard, there are loupes available with higher magnifications (e.g., 20x, 30x) for more detailed inspection. However, 10x is generally the ideal magnification for most grading purposes.
Lens Quality:

A high-quality diamond loupe is typically made with achromatic lenses to reduce colour distortion and correct for chromatic aberrations, ensuring clear and accurate magnification. Loupes must be carefully crafted to ensure that they do not distort the image, especially when examining tiny inclusions or imperfections within the diamond.
The lenses in a good diamond loupe should also be free from spherical aberration, which can cause the image to appear blurry around the edges. This is essential for accurate evaluation.
Optical Clarity:

The lens of the loupe should provide a sharp, crisp image, free of distortions, allowing the user to easily identify the smallest of inclusions and other characteristics. Diamond clarity, which includes the presence of natural inclusions and surface blemishes, is assessed based on the ability to see these minute details under magnification.
Purpose of a Diamond Loupe in Clarity Grading
Clarity Assessment:

When grading the clarity of a diamond, a loupe is used to inspect the stone under 10x magnification to determine the size, location, and nature of any inclusions or blemishes present inside or on the surface of the diamond. The Gemological Institute of America (GIA), for example, uses this tool when assigning clarity grades to diamonds.
Diamonds with fewer or no inclusions are typically given higher clarity grades (such as Flawless or Internally Flawless), while diamonds with more visible inclusions or surface blemishes are graded lower (e.g., SI1, SI2).
Inclusion Identification:

A diamond loupe is indispensable for identifying inclusions such as clouds, crystals, pinpoints, and feathers within the diamond. These inclusions can affect the diamond’s clarity and its overall value. The clarity grade is based on the number, size, location, and visibility of these imperfections, making the loupe an indispensable tool for any professional examining diamonds.
Blemishes on the surface of a diamond, such as scratches, chips, or natural marks, are also easily visible under magnification, helping in the evaluation of the stone’s overall appearance and quality.
Facets Inspection:

While the loupe is primarily used to examine clarity, it is also useful for assessing the quality of the cut. A skilled observer can identify issues with facet alignment, polish, and symmetry that might not be noticeable with the naked eye. The loupe allows professionals to examine whether the facets meet at the correct angles and whether the diamond exhibits good brilliance and scintillation.
Types of Diamond Loupes
Single-Lens Loupe:

The most common and traditional type of loupe, a single-lens loupe typically has a fixed 10x magnification. It is compact and portable, fitting comfortably in a jeweller’s pocket. The single lens makes it simple to use, and it is widely regarded as the standard tool for diamond clarity grading.
Triplet Loupe:

A triplet loupe features three lenses, which are fused together to form a single lens system. This design allows for better correction of optical distortions, particularly spherical and chromatic aberration, providing clearer and more accurate magnification. While often slightly more expensive, triplet loupes are preferred by professionals for their superior clarity.
Binocular Loupe:

A binocular loupe uses two lenses, providing a wider field of view and a more comfortable viewing experience, as it reduces eye strain compared to using a single-lens loupe. While it is not as portable as a single-lens loupe, it offers more detailed and comfortable magnification for longer periods of use.
How to Use a Diamond Loupe
Proper Positioning:

To get the most accurate magnification, position the loupe about 1–2 inches from the surface of the diamond. Hold the loupe up to your eye and move the diamond until it is in focus. The clarity of the diamond will become more apparent as you carefully examine its surface and internal characteristics.
It’s important to hold the diamond steady while examining it to ensure that the details are clearly visible. Some jewellers use diamond holders or trays to secure the stone during examination.
Lighting Conditions:

Lighting plays a critical role in clarity grading. A bright, focused light source, such as a desk lamp with a white light or a gemlight, is often used to illuminate the diamond while using a loupe. Proper lighting helps illuminate inclusions and other features, making them more visible and easier to assess.
Examine the Diamond in Sections:

When inspecting a diamond, it’s important to examine it systematically, looking at all sides and angles. Start by inspecting the table (the flat top surface), and then move to the crown, pavilion, and girdle. Rotate the diamond as you look through the loupe to get a comprehensive view of its clarity.
Maintaining Your Diamond Loupe
Cleaning:
Since a diamond loupe is used to examine the smallest details, it’s crucial to keep the lens clean. Smudges or dirt can obscure the clarity of the diamond, making it difficult to evaluate. Use a microfiber cloth or a lens cleaning solution to gently clean the loupe lens.
Storage:
Store the loupe in a protective case when not in use to prevent scratches or damage to the lens. A well-maintained loupe will provide accurate and reliable results for many years.

July, 2017February, 2025

Loose Diamond

A loose diamond refers to a diamond that is not yet set in any type of jewellery. It is an unmounted stone that remains free, allowing for a more detailed assessment of its qualities before it is placed into a setting such as a ring, necklace, or bracelet. This freedom provides several benefits, including a clearer understanding of the diamond’s characteristics and the flexibility for buyers to choose their preferred mounting.

Importance of Loose Diamonds in the Jewellery Industry
Accurate Evaluation:

When a diamond is loose, its attributes—such as its cut, colour, clarity, and carat weight (the Four Cs)—can be accurately assessed. The diamond is viewed from all angles, and precise measurements can be made. This allows for a thorough and precise evaluation, which is impossible when the diamond is set in jewellery, as the setting may obscure parts of the stone.
Grading labs, such as the Gemological Institute of America (GIA) or the Diamond Certification Laboratory of Australia (DCLA), require diamonds to be loose for accurate certification. When a diamond is mounted, it may be challenging to fully assess certain characteristics, especially clarity, as inclusions might be hidden by the setting.
Better Market Transparency:

Loose diamonds provide greater transparency in the marketplace. Buyers can inspect and compare the characteristics of different diamonds in their natural state. This also allows for greater flexibility in selecting the right stone for a specific piece of jewellery, as customers have the option to customise the setting later based on the loose diamond’s shape and size.
Advantages of Purchasing a Loose Diamond
Customisation:

Purchasing a loose diamond allows the buyer to have full control over the design of their jewellery. Whether it’s for an engagement ring, a pendant, or earrings, customers can choose the setting that best complements their diamond, resulting in a more personalised and unique piece of jewellery.
Loose diamonds also provide the opportunity to create bespoke designs, as they are not restricted to pre-existing settings. Buyers can work with a jeweller to design something that reflects their personal style and preferences.
Cost Efficiency:

A loose diamond may be more affordable than a pre-set diamond in a piece of jewellery, as you are only paying for the stone itself without the cost of the setting. Additionally, buying loose allows buyers to explore different pricing options, including different grading and certification levels, without paying for an expensive mount.
The cost of setting a loose diamond is a separate consideration, but in many cases, the buyer may save on the mounting compared to purchasing an already mounted diamond.
Greater Selection:

Buying a loose diamond offers a wider selection of stones. You are not limited to the diamonds that are already set in jewellery, which may not fit your preferences in terms of quality, shape, or size. Loose diamonds give access to a broader variety of shapes (round, princess, oval, emerald, etc.), sizes, and grades, allowing you to choose a diamond that best suits your needs.
Investment Potential:

Loose diamonds are also popular with investors. They are portable, can be easily stored, and often maintain or increase their value over time, especially high-quality diamonds with favourable characteristics. As the diamond market continues to evolve, loose diamonds provide the flexibility to resell or trade them more easily compared to mounted diamonds.
Challenges of Loose Diamonds
Vulnerability to Damage:

While being unmounted offers several benefits, it also leaves the diamond more exposed to damage. Without a setting to protect it, a loose diamond can be scratched, chipped, or lost more easily. Buyers should take extra care when handling and storing loose diamonds to avoid accidental damage.
Secure packaging and proper storage are critical to maintain the diamond’s condition.
Setting Delays:

After purchasing a loose diamond, the buyer may face delays in having the stone set into their chosen jewellery. The setting process can take time, especially if custom work is involved, and the jewellery itself may not be ready for immediate wear.
It is important to account for the time it takes to create the jewellery around the diamond, which may affect when the customer can actually wear or present the piece.
Loose Diamond Certification
Loose diamonds are typically certified by independent gemological laboratories. This certification ensures that the diamond has been graded and evaluated according to universally recognised standards. The Four Cs (cut, colour, clarity, and carat weight) are the main criteria used to assess the quality of a diamond.

Cut: The diamond’s proportions, symmetry, and polish. This affects how well the diamond reflects light, influencing its brilliance and overall appearance.
Colour: The lack of colour in the diamond. Diamonds are graded on a scale from D (colourless) to Z (light yellow or brown).
Clarity: The presence of internal or external flaws, called inclusions and blemishes. The fewer the imperfections, the higher the clarity grade.
Carat Weight: The weight of the diamond, with one carat equalling 200 milligrams. Larger diamonds are rarer and typically more valuable.
Certification provides reassurance to buyers that the diamond meets certain standards and helps them understand its true value. The report usually includes a diagram of the diamond’s inclusions and any other notable features, which are critical for understanding its characteristics.

Where to Buy Loose Diamonds
Loose diamonds can be purchased from a variety of sources:

Jewellers and Diamond Retailers: Many well-established jewellers offer loose diamonds for sale. Some may also have diamond grading reports available for each stone, giving buyers more confidence in their purchase.

Online Platforms: Online marketplaces and diamond retailers provide access to a large selection of loose diamonds, often with detailed information about each stone’s grading and certification. Some platforms even allow buyers to filter diamonds based on specific criteria, such as carat weight, cut quality, and colour.

Diamond Auctions: For collectors and investors, diamonds can also be found at diamond auctions, where high-quality loose diamonds are sold to the highest bidder.

July, 2017February, 2025

Life

Life in a diamond refers to the vivid, dynamic quality that gives the diamond its captivating brilliance, dispersion, and scintillation. It is the essence of what makes a diamond sparkle and appear alive under different lighting conditions. While many factors contribute to the overall aesthetic of a diamond, the concept of “life” encompasses how the diamond interacts with light, its ability to reflect and refract light, and the visual impact it has on the viewer.

Key Components of Life in a Diamond
The term “life” is a combination of three key optical phenomena that work together to create the diamond’s stunning visual effects. These include brilliance, dispersion, and scintillation:

Brilliance:

Brilliance refers to the amount of white light that is reflected from the surface and the facets of a diamond. It is a measure of how much light is returned to the viewer’s eye, creating a sparkling, bright effect.
The quality of brilliance depends heavily on the cut of the diamond. Well-cut diamonds with optimal proportions and angles will exhibit the maximum amount of brilliance. When a diamond is cut properly, the light entering through the top is reflected back through the table and facets, creating an intense, white sparkle.
Dispersion:

Dispersion, also known as “fire,” is the effect that occurs when light is split into its constituent colours as it passes through the diamond. This creates the colourful flashes of light that you often see in high-quality diamonds, particularly in sunlight or bright lighting.
The greater the dispersion, the more the diamond will show a rainbow of colours, enhancing its visual beauty. A well-cut diamond will maximise the effect of dispersion, allowing it to reflect the full spectrum of visible light.
Scintillation:

Scintillation refers to the flashes of light and sparkle that appear as the diamond moves. These flashes are the result of light being reflected off the facets of the diamond as it is tilted or rotated.
The more facets a diamond has, and the better its proportions, the greater the scintillation effect. A diamond with excellent scintillation will have a lively, dynamic sparkle, even when viewed from different angles or when moved slightly.
The Role of Cut in Life
The cut of a diamond is the most significant factor influencing its life. The cut determines how well a diamond interacts with light, affecting its brilliance, dispersion, and scintillation. An ideal cut maximises all of these attributes by ensuring that light enters, reflects, and exits the diamond in the most efficient manner possible.

Proportions and Symmetry: Proper proportions and symmetry are critical in the cut of the diamond. A well-cut diamond ensures that the angles of the facets are aligned in such a way that light is properly reflected and refracted, leading to maximum brilliance and fire.

Polish: The quality of the diamond’s polish also impacts its life. A poorly polished diamond may have rough surfaces that cause light to scatter unevenly, reducing brilliance and fire. On the other hand, a well-polished diamond will allow light to enter and exit smoothly, enhancing its sparkle.

Why Life Matters in a Diamond
Visual Appeal: The “life” of a diamond is what attracts the eye and creates the allure that diamonds are known for. The more vibrant and sparkling a diamond appears, the more attractive it will be to the observer. Life adds depth and dimension to the diamond, making it look stunning from all angles.

Value: A diamond with excellent life is often more valuable because it is more visually striking. Diamonds that display higher levels of brilliance, dispersion, and scintillation tend to be more desirable, thus commanding higher prices in the market.

Emotional Impact: A diamond’s life can evoke emotions, especially when it is worn in jewellery such as engagement rings or necklaces. The way a diamond sparkles and shifts with the light can symbolise significant moments or memories, making the emotional value of the stone even greater.

Evaluating Life in a Diamond
When purchasing or evaluating a diamond, the life is an essential consideration. However, unlike colour, clarity, and carat weight, “life” is a more subjective aspect of the diamond. It is not usually quantified on a grading scale, but instead evaluated based on its visual impact.

Lighting Conditions: The effect of life can vary depending on the lighting environment. A diamond might look stunning in natural sunlight, but may appear less lively under low or artificial lighting. For this reason, it’s important to view diamonds in different lighting conditions to fully appreciate their brilliance and fire.

Personal Preference: Life in a diamond can also be subjective based on individual preferences. Some people prefer a diamond with a more intense sparkle, while others may appreciate a subtler effect. Different cuts, such as round brilliant or cushion cut, will exhibit life in unique ways.

Life in the Diamond Industry
Marketing and Presentation: In the diamond industry, life plays a significant role in marketing. Diamonds with exceptional brilliance and sparkle are often highlighted as being “extraordinarily lively,” creating a sense of awe and desire among potential buyers. This makes life an important selling point in the jewellery market.

Technology and Innovations: Advances in cutting technology have greatly improved the life of diamonds. Modern cutting machines allow for greater precision in shaping diamonds, leading to cuts that maximise light reflection and enhance the diamond’s overall beauty. Additionally, the use of advanced techniques such as laser cutting ensures that diamonds have more symmetrical and finely polished facets, resulting in a greater display of life.

July, 2017February, 2025

Laser Drilling

Laser drilling is a treatment used to enhance the apparent clarity of a diamond by reducing the visibility of dark inclusions. It involves the use of a focused laser beam to create a small tunnel through the diamond’s surface, allowing the removal or bleaching of inclusions, particularly dark ones. This process is commonly used to improve the visual appeal of diamonds with noticeable inclusions, making them more attractive to potential buyers. While laser drilling is an effective technique, it’s important to understand its process, benefits, and potential drawbacks.

The Laser Drilling Process
Laser drilling is a highly precise technique that typically follows these steps:

Identification of Inclusions: Before the drilling process begins, the diamond is thoroughly examined to identify the inclusions that can be treated. Dark inclusions, such as black carbon spots or crystals, are the primary targets of this treatment, as they are often the most visible and detrimental to a diamond’s clarity.

Laser Penetration: Once the target inclusions are located, a small laser beam is directed at the diamond. The laser drills a tiny tunnel from the surface to the inclusion, carefully creating a channel that reaches the inclusion without compromising the integrity of the diamond. This process is highly precise, and the depth and location of the drill are controlled to ensure the best possible results without causing damage.

Inclusion Removal or Bleaching: After the tunnel is created, the dark inclusion inside the diamond is either:

Vaporised: In some cases, the laser’s intense heat will cause the dark material in the inclusion to evaporate, making it less noticeable.
Bleached: Alternatively, if the inclusion is resistant to laser vaporisation, the material is often bleached with a mild acid solution. This is particularly effective for black carbon or graphite inclusions. The bleaching process lightens or removes the dark colour, making the inclusion less visible to the naked eye.
Surface Finishing: After the treatment, the surface of the diamond may require some polishing or additional treatment to restore its smoothness and appearance. The treated areas are carefully examined to ensure that the diamond’s clarity is visibly improved.

Types of Inclusions Treated by Laser Drilling
Laser drilling is most commonly used to treat specific types of inclusions, primarily those that significantly affect a diamond’s clarity and appearance:

Black Inclusions: These are often caused by carbon or graphite inclusions, which appear as dark spots or crystals inside the diamond. These inclusions are particularly noticeable and can dramatically affect the visual quality of the diamond. Laser drilling is effective in removing or lightening these dark inclusions.

Crystal Inclusions: If a crystal inclusion is dark in colour, laser drilling may be used to reduce its visibility. Crystal inclusions are common in diamonds, and laser drilling can help make them less conspicuous without affecting the structural integrity of the diamond.

Feathers: In some cases, laser drilling can be used to treat smaller feather-like inclusions that have a darker colour. While the primary purpose of laser drilling is to target black inclusions, it can sometimes be effective for other types of inclusions that detract from the diamond’s clarity.

Benefits of Laser Drilling
Improved Clarity: The main benefit of laser drilling is its ability to significantly enhance the clarity of a diamond. By reducing the visibility of dark inclusions, the diamond appears clearer and more visually appealing, which can increase its marketability and value.

Preserving Diamond Integrity: Unlike some other clarity-enhancing treatments, laser drilling does not compromise the structural integrity of the diamond. The process is highly precise and controlled, ensuring that the diamond remains intact and safe for regular wear.

Affordable Alternative to Higher-Quality Diamonds: Laser drilling can be a more cost-effective solution for diamonds that would otherwise be deemed lower in clarity. This treatment can make diamonds with minor inclusions more appealing, potentially allowing them to be sold at a higher price point.

Customised Treatment: The precision of the laser drilling process means that diamonds can be treated on a case-by-case basis. This customisation allows diamond professionals to target only the inclusions that are most visible and impactful, ensuring that the treatment is both effective and minimally invasive.

Drawbacks and Considerations
While laser drilling offers several benefits, it’s important to consider the potential drawbacks of this treatment:

Visible Marks on the Surface: Laser drilling creates small tunnels or entry points on the diamond’s surface. Although these are typically very small and can be polished after treatment, they may still be visible under magnification. These marks can slightly detract from the overall appearance of the diamond, particularly in higher magnification grades.

Affecting Diamond Value: While laser drilling can improve the clarity of a diamond, it is important to note that diamonds treated with laser drilling may be graded differently than untreated diamonds. In some cases, diamonds that have undergone laser drilling may be valued lower than those with naturally high clarity because the treatment is considered an enhancement, rather than a natural characteristic.

Potential Disclosure Requirements: If a diamond has been laser drilled, it must be disclosed to potential buyers. Ethical guidelines and diamond grading standards require that treatments such as laser drilling be properly documented and disclosed, which means buyers will be aware of the enhancement.

Limitations on Severe Inclusions: While laser drilling can be highly effective for small dark inclusions, it is not always appropriate for larger or more complex inclusions. For example, if the inclusion extends too far into the diamond, or if it is located in a position where drilling is difficult or would risk damaging the diamond, laser drilling may not be feasible.

Laser Drilling vs. Other Diamond Treatments
Clarity Enhancement via Bleaching: Laser drilling is often used in conjunction with other clarity-enhancing treatments such as laser bleaching, where the dark inclusion is lightened with acid. While both techniques aim to reduce the visibility of inclusions, laser drilling focuses on creating a tunnel to remove or lighten the inclusion, while bleaching lightens the inclusion chemically.

Fracture Filling: Another clarity-enhancing treatment is fracture filling, which involves filling small fractures or inclusions with a substance such as glass or resin to make them less visible. Laser drilling is sometimes used in conjunction with fracture filling to target dark inclusions that are visible on the diamond’s surface.

July, 2017February, 2025

Knot

A knot is a specific type of inclusion found within diamonds. It refers to an included crystal or foreign material that is embedded within the diamond, and in certain cases, it extends all the way to the surface of the stone, disrupting the clarity of the diamond. The knot can sometimes result in a visible raised or burnt area on the diamond’s surface, which may affect both the diamond’s appearance and its overall value.

Formation and Characteristics of a Knot
A knot is formed when a crystal or a foreign material becomes trapped within the diamond during its crystallization process. These inclusions are often caused by other minerals, such as garnet, graphite, or pyrite, which can become incorporated into the diamond’s crystal structure as it forms deep within the Earth’s mantle. These inclusions, when they grow to a size large enough and reach the surface of the diamond, are identified as knots.

The key characteristics of a knot include:

Size: Knots can vary in size, but they are generally larger than many other types of inclusions.
Shape: A knot is often irregularly shaped, with rough edges that can be visible within the diamond.
Visibility: When a knot reaches the surface, it may be visible to the naked eye or under magnification, depending on its size and location.
Effect of a Knot on Diamond Clarity
Inclusions, including knots, are important factors in determining the clarity grade of a diamond. The presence of a knot can significantly reduce a diamond’s clarity, depending on its size, location, and visibility. Since clarity is one of the key factors in diamond grading, knots are generally considered undesirable, especially if they are prominent or affect the overall appearance of the diamond.

The primary impacts of a knot on clarity are:

Lower Clarity Grade: Knots are typically graded as part of the diamond’s clarity assessment. A diamond with a visible knot on the surface may be downgraded in clarity compared to a similar diamond with fewer inclusions or no knots.
Potential for Weakening the Diamond: While knots do not always affect a diamond’s durability, they can sometimes create weak points. If a knot is close to the surface, it may potentially make the diamond more susceptible to damage, such as chipping or cracking.
Visual Appearance of a Knot
When a knot breaks through the surface of the diamond, it can sometimes leave a visible mark, which could be a slightly raised area or a burnt-looking spot. These marks can appear darker or different in texture than the surrounding surface of the diamond. In some cases, knots may appear as small, black or dark spots, particularly if the included crystal is dark or opaque.

Since the surface of a diamond is a key aspect of its overall appearance, the presence of a knot can have an impact on how light interacts with the stone, potentially reducing its brilliance or sparkle. However, in some cases, the knot may be positioned in such a way that it does not significantly affect the diamond’s aesthetic quality.

Impact of Knots on Diamond Value
Knots can reduce a diamond’s market value, as they negatively affect its clarity and appearance. The extent of the impact on value depends on several factors:

Size of the Knot: Larger knots, particularly those visible to the naked eye, will generally result in a more significant reduction in value.
Location of the Knot: Knots located in more visible areas, such as the crown or table, will have a greater impact on the diamond’s appearance and thus its value. Conversely, knots located on the pavilion (bottom) or near the girdle may be less noticeable.
Number of Knots: Diamonds with multiple knots may be valued lower than those with fewer or no inclusions. However, some diamonds may contain one or two small knots that do not significantly affect their overall appearance or value.
Knot vs. Other Inclusions
While a knot is a relatively specific type of inclusion, it is useful to compare it with other types of diamond inclusions:

Crystal: Similar to a knot, a crystal is an inclusion of another mineral within the diamond. However, unlike a knot, a crystal does not necessarily break through the surface of the diamond.
Feather: A feather is another inclusion that can sometimes reach the surface of the diamond. Unlike knots, feathers are typically fissures or cracks in the diamond that may or may not affect the clarity grade.
Needle: A needle inclusion is a thin, elongated inclusion that does not typically reach the surface of the diamond, and thus may not be as impactful as a knot.
Treatment of Knots
In some cases, diamond cutters may attempt to minimise the visual impact of a knot by carefully positioning it or by using techniques like laser drilling to remove or reduce the visibility of inclusions. However, the presence of a knot often cannot be completely eliminated, particularly if the knot is close to the surface.

Additionally, some diamonds with prominent knots may be treated by laser inscription, which may help with traceability but will not alter the presence of the knot itself.

July, 2017February, 2025

Kimberlite

Kimberlite is an igneous rock, typically blue or green in colour, from which most diamonds are mined. It is of particular interest in the study of diamonds because it serves as the primary host rock for the formation and occurrence of these precious stones. Kimberlite is found in specific geological structures known as kimberlite pipes, which are deep, vertical fissures or conduits in the Earth’s crust. These pipes were formed by volcanic activity, and they are the main source of natural diamonds that are mined today.

Formation and Composition of Kimberlite
Kimberlite is an ultramafic rock, meaning it contains a high proportion of magnesium and iron, with low silica content. The primary components of kimberlite include:

Olivine: A green mineral that is a common constituent of kimberlite, contributing to its characteristic colour.
Pyroxenes: A group of minerals that also form part of kimberlite’s composition.
Carbonates: Minerals such as calcite and dolomite can be found in kimberlite, sometimes in large quantities.
Clay Minerals and Volcanic Ash: In some cases, kimberlite also contains elements derived from the surface, such as clay minerals or volcanic debris.
Diamond Crystals: Most notably, kimberlite contains diamonds, though the quantity and size of these diamonds vary.
The volcanic activity responsible for the formation of kimberlite pipes involves the eruption of magma from deep within the Earth’s mantle. This magma, under extremely high pressure and temperature, ascends through the Earth’s crust, bringing with it diamonds that formed under similar high-pressure conditions. Kimberlite, upon solidification, traps these diamonds within the rock, where they remain until mining operations bring them to the surface.

Kimberlite Pipes: The Primary Source of Diamonds
The most famous source of diamonds, kimberlite pipes, are vertical geological formations that originate from deep beneath the Earth’s surface. These pipes are often cylindrical in shape, and their formation is associated with ancient volcanic eruptions. As the magma ascends through the Earth’s crust, it forms a narrow, funnel-like conduit. Over millions of years, erosion and weathering can expose kimberlite pipes, allowing diamond mining to occur.

These pipes are typically surrounded by much older and harder rocks, often making it difficult to access the diamonds. The kimberlite itself can also contain other valuable minerals such as garnet, ilmenite, and chromite, but it is the diamonds embedded within the kimberlite that are the primary target of mining efforts.

The Role of Kimberlite in Diamond Mining
Kimberlite plays a crucial role in the discovery and extraction of diamonds. Mining operations often target kimberlite pipes, as they are the most reliable source of diamonds in nature. The process of mining kimberlite involves:

Exploration: Geologists and prospectors search for kimberlite pipes using various techniques such as aerial surveys, satellite imagery, and ground sampling. The distinctive blue or green colour of the rock can also be used as an indicator of its presence.

Extraction: Once a kimberlite pipe is located, it is typically extracted through either open-pit or underground mining techniques. Open-pit mining involves removing large quantities of surface material to reach the kimberlite layer, while underground mining involves digging shafts to reach deeper deposits.

Processing: After kimberlite is extracted, it is crushed and sorted to separate the diamonds from the surrounding rock and other minerals. This is typically done through a combination of mechanical crushing, gravity separation, and sometimes, advanced techniques such as X-ray sorting or dense media separation.

Geological and Geographic Distribution of Kimberlite
Kimberlite is found in specific geographic regions, primarily in ancient cratons—stable areas of the Earth’s crust that have remained relatively undisturbed for billions of years. These regions include:

Africa: The continent is home to several large kimberlite pipes, including the famous Kimberley Mine in South Africa, which has been historically significant for diamond mining.
Russia: Russia contains several diamond-producing kimberlite pipes, particularly in Siberia, with the Yakutia region being a major source of diamonds.
Canada: The discovery of kimberlite pipes in Canada’s Northwest Territories led to the establishment of large-scale diamond mining operations, such as the Ekati and Diavik mines.
Australia: The Argyle Mine in Western Australia, which produces significant quantities of pink and red diamonds, is also a notable source of kimberlite.
While kimberlite pipes are present on all continents, the largest and most significant diamond-producing regions are found in Africa, Russia, and Canada.

Importance and Rarity of Kimberlite Pipes
While kimberlite pipes are the main source of natural diamonds, they are relatively rare. The conditions required for kimberlite formation are very specific, and only a small number of these pipes have been discovered and mined for diamonds. Geologically speaking, kimberlite pipes are often formed in ancient and stable parts of the Earth’s crust, where volcanic activity can reach the depths necessary for diamond formation.

The rarity and difficulty of accessing kimberlite pipes make diamonds sourced from these pipes valuable commodities. The unique geological conditions under which kimberlite forms, combined with the rarity of pipes, contribute to the high value of diamonds that originate from these sources.

Kimberlite vs. Lamproite: Other Sources of Diamonds
While kimberlite is the most well-known source of diamonds, lamproite is another type of volcanic rock that can also host diamonds. Lamproite is less common than kimberlite, but some significant diamond deposits, such as those at the Argyle Mine in Australia, have been discovered in lamproite pipes. However, kimberlite remains the more prominent and studied source of diamonds worldwide.

July, 2017February, 2025

Kimberley Process

The Kimberley Process (KP) is an international certification scheme established to prevent the trade in “blood diamonds,” which are diamonds mined in war zones and sold to finance armed conflict against governments. The Kimberley Process aims to ensure that diamonds are sourced from legitimate, conflict-free origins, and is designed to trace a diamond’s journey from its rough state through to its finished form.

Background and History
The Kimberley Process was established in 2003, following years of efforts to address the issue of conflict diamonds. The trade in blood diamonds was particularly prevalent during the 1990s, when diamonds were being used as a source of funding for rebel groups in countries like Sierra Leone, Angola, and the Democratic Republic of Congo. These diamonds were sold to finance armed conflicts, often at the expense of innocent civilians who were subjected to violence, forced labor, and exploitation.

In response to growing international concern, governments, industry leaders, and non-governmental organisations (NGOs) came together to create the Kimberley Process Certification Scheme. The scheme aims to prevent diamonds that fund violence from entering the global market, by ensuring that all rough diamonds are certified as conflict-free before they can be traded.

How the Kimberley Process Works
The Kimberley Process works by requiring the certification of all rough diamonds being traded internationally. The certification process ensures that the diamond in question has been sourced from a country that is compliant with the Kimberley Process rules, which prohibit the trade of diamonds that finance conflict.

The key aspects of the Kimberley Process include:

Certification of Origin: Each shipment of rough diamonds must be accompanied by a Kimberley Process certificate that attests that the diamonds come from a conflict-free source. The certificate contains information about the diamond’s country of origin, as well as details about the trading parties involved in the transaction.

International Trade Regulation: The Kimberley Process applies to the international trade of rough diamonds. It requires that all rough diamonds be shipped in secure, tamper-resistant containers and that they are accompanied by the appropriate certificates at every stage of the trade process.

Export and Import Controls: Countries participating in the Kimberley Process are required to implement strict controls over the export and import of rough diamonds. Diamonds that do not have the appropriate Kimberley Process certificate are not allowed to enter international trade.

Monitoring and Compliance: To ensure that participating countries adhere to the Kimberley Process, there are monitoring mechanisms in place. Each participating country is required to report on its compliance with the Kimberley Process rules, and there are provisions for addressing non-compliance, including sanctions or trade restrictions.

Participating Countries and Stakeholders
The Kimberley Process is a voluntary initiative, with over 80 countries currently participating, including diamond-producing countries such as South Africa, Botswana, Russia, and Canada. Key stakeholders in the Kimberley Process include:

Governments: Each participating government is responsible for implementing the Kimberley Process within its own jurisdiction. This includes enacting legislation, establishing regulatory bodies, and ensuring compliance with the certification requirements.

Diamond Industry: Diamond producers, traders, and manufacturers play a critical role in the Kimberley Process. Companies must ensure that the diamonds they trade are conflict-free and that they comply with the certification system. Many diamond industry leaders and organisations, including the World Diamond Council, support the Kimberley Process and encourage ethical business practices within the industry.

Non-Governmental Organisations (NGOs): NGOs, such as Global Witness, have been instrumental in raising awareness about the issue of conflict diamonds and advocating for strong measures to address the problem. NGOs continue to monitor the Kimberley Process and push for improvements in its effectiveness.

The United Nations: The United Nations (UN) has been involved in supporting the Kimberley Process, particularly in the context of enforcing trade restrictions and sanctions against countries or regions that fail to comply with the certification scheme.

The Impact of the Kimberley Process
The Kimberley Process has had a significant impact on the global diamond trade. By providing a certification system that ensures diamonds are sourced from conflict-free areas, the initiative has helped reduce the flow of blood diamonds into international markets. Some of the key outcomes of the Kimberley Process include:

Reduction in Conflict Diamonds: The Kimberley Process has significantly decreased the number of conflict diamonds entering the market. The system has made it more difficult for diamonds mined in war zones to be traded internationally, thereby cutting off an important source of funding for rebel groups involved in armed conflicts.

Increased Accountability in the Diamond Trade: The certification requirements of the Kimberley Process have improved transparency and accountability in the diamond trade. By tracking the origin of diamonds, the system helps ensure that diamonds are ethically sourced and do not contribute to violence or human rights abuses.

Support for Ethical Practices in the Industry: The Kimberley Process has encouraged the diamond industry to adopt more responsible and sustainable practices. Many companies in the industry now prioritise sourcing diamonds from conflict-free areas and are increasingly committed to maintaining ethical supply chains.

Criticism and Challenges
While the Kimberley Process has achieved significant success, it is not without its critics and challenges. Some of the issues raised include:

Loopholes and Weak Enforcement: Despite its successes, the Kimberley Process has faced criticism for its enforcement mechanisms. There have been concerns about the presence of loopholes that allow diamonds from conflict zones to still enter the market, particularly through illegal or unregulated trade routes.

Limited Scope: The Kimberley Process only covers rough diamonds and does not extend to polished diamonds or diamonds that have been integrated into finished jewellery. This leaves some potential gaps in the supply chain where conflict diamonds could still enter the market.

Conflict Beyond Diamonds: The Kimberley Process only addresses the issue of conflict diamonds, but does not tackle the broader issues of human rights abuses, environmental harm, or unethical practices that can be associated with the diamond trade.

Lack of Effective Monitoring: Some critics argue that the monitoring and verification processes within the Kimberley Process are insufficient and that there is a lack of consistent oversight to ensure full compliance.

The Future of the Kimberley Process
While the Kimberley Process has made important strides in addressing the issue of conflict diamonds, there is ongoing debate about how to improve and strengthen the system. Several key areas for reform include:

Expanding the Scope of Certification: There are calls for expanding the Kimberley Process to include polished diamonds and finished jewellery, as well as addressing other forms of exploitation and unethical practices in the diamond industry.

Improved Monitoring and Enforcement: Strengthening monitoring mechanisms and ensuring better enforcement of the certification rules is crucial to preventing diamonds from conflict zones from entering the market.

Increased Transparency: Increased transparency in the diamond supply chain, including the use of technology to track diamonds from mine to market, can help to further combat the issue of conflict diamonds.

The Kimberley Process remains an important tool in the global effort to ensure that diamonds are sourced ethically and do not contribute to conflict. As the industry evolves, so too will the Kimberley Process, with ongoing efforts to improve its effectiveness and expand its impact on the diamond trade.