Tag: Diamonds

A broad scale of diamond colour grades that ranges from a near colourless, almost undetectable pale yellow to increasingly tinted yellow. Once it has enough yellow saturation to qualify as a fancy colour, it is no longer called a Cape Series diamond.

Cape Series Diamonds refer to a category of diamonds that exhibit a noticeable yellow or brown tint due to the presence of nitrogen in their crystal structure. The term originates from the Cape Province of South Africa, where these diamonds were historically mined in large quantities.

Characteristics of Cape Series Diamonds:
Colour Range

These diamonds fall within the near-colourless to light yellow range on the GIA D–Z colour scale.
They typically appear in the K to M range, but some can extend beyond, showing a deeper yellow tint.
Unlike Fancy Yellow Diamonds (such as Canary Diamonds), Cape Series Diamonds do not have the intense saturation needed to be classified as “fancy colour diamonds.”
Cause of Yellow Tint

The yellowish hue comes from nitrogen impurities, which absorb blue light and make the diamond appear slightly yellow.
The higher the nitrogen concentration, the stronger the yellow tint.
Historical Significance

The name “Cape Series” comes from South Africa’s Cape Province, where many of these diamonds were first discovered in the late 19th century.
These diamonds were highly valued in the early days of diamond mining, especially before the discovery of purer, colourless diamonds.
Market Perception & Value

Higher Colour Grades (K–M): Often sold at a discount compared to colourless diamonds (D–F), making them an affordable option for buyers.
Lower Grades (N–Z): Can exhibit a stronger yellow tone, appealing to those who prefer warm-toned diamonds.
Well-cut Cape Series Diamonds can still appear brilliant, especially in round brilliant and cushion cuts, which minimize visible colour.
Modern Use

Many Cape Series Diamonds are set in yellow gold settings to enhance their warmth and reduce contrast.
Some are reclassified as “faint yellow” fancy diamonds if their colour saturation is strong enough.

The Calf’s Head Diamond is a historic and notable diamond that is part of British royal history. It has a distinctive shape and was owned by several prominent figures over the centuries.

Key Facts About the Calf’s Head Diamond:
Appearance and Characteristics

The Calf’s Head Diamond is known for its unique shape, which is said to resemble the head of a calf. It is a fancy-shaped diamond, with its unusual appearance contributing to its historical and cultural significance.
It is reported to have a yellowish or light brown hue, adding to its distinctiveness compared to the more typical clear diamonds.
Historical Background

This diamond has been part of the British royal collection and is known to have passed through various notable hands.
It was famously owned by King Charles II of England. During his reign, it was said to be part of the crown jewels.
Symbolism and Significance

The Calf’s Head Diamond is believed to symbolize wealth, nobility, and royalty due to its connection to the monarchy.
The diamond’s unusual shape and connection to the English monarchy have made it a subject of historical intrigue.
Current Status

The location of the Calf’s Head Diamond today is uncertain, and its current whereabouts are not widely known, adding to the mystery surrounding this remarkable gem.

A bruted diamond girdle refers to the technique used in the finishing process of a diamond, specifically around the diamond’s outer edge, known as the girdle. The term “bruted” comes from the method of shaping and polishing the girdle using a rotating wheel or tool to smooth out any roughness, creating a rounded, slightly frosted surface.

Bruting is often one of the first steps in diamond cutting and involves shaping the girdle into a uniform form, helping to define the diamond’s proportions. The girdle itself is an important feature because it serves as the boundary between the crown (top) and pavilion (bottom) of the diamond.

When a diamond is bruted, the girdle typically has a polished or frosted finish, depending on the diamond cutter’s technique. A bruted girdle is often seen in diamonds that are of higher quality, as it helps ensure the symmetry and overall aesthetic appeal of the finished stone.

The bruted girdle may or may not show additional markings, such as laser inscriptions, which are commonly used for identification purposes.

A briolette diamond is a unique and beautiful cut that features a tear-drop or pear shape with triangular facets all over the surface. It’s one of the oldest diamond cuts, often associated with antique and vintage jewelry. The briolette cut is characterized by its 360-degree faceting, which makes the diamond sparkle from every angle. It’s typically used in pendants or earrings because of its distinctive shape and the way it captures light.

This cut is known for its exceptional brilliance due to the numerous facets that create a dynamic play of light. Briolette diamonds are often more challenging to work with because of their shape, but they can be a striking feature in high-end, custom pieces. They are also considered a symbol of elegance and sophistication.

Diamond briefca (sometimes spelled briefcase or brief), which is a small, folded, envelope-like paper used to safely hold a diamond. These are commonly used in the diamond trade for secure packaging and easy identification of diamonds, especially when they are being transported or stored temporarily.

Key Features of a Diamond Briefca:
Protective Packaging:

The diamond briefca is designed to protect the diamond from physical damage, such as scratches or chipping, while being stored or transported.
It is made from durable paper or a similar material that folds securely to create a compact, protective enclosure.
Identification Information:

The outside of the briefca typically features printed or handwritten details about the diamond, such as its certification number, weight, cut, colour, and clarity.
If the diamond is certified, the information often includes references to the grading laboratory (like DCLA), the diamond’s certification report, and any unique identifiers for the diamond, ensuring traceability and authenticity.
Use in the Trade:

Briefcas are commonly used in wholesale transactions and diamond exchanges, where diamonds need to be transported securely between dealers, gemologists, or jewelers.
They are also used to package loose diamonds being sent to grading laboratories for certification.
Security Features:

Some diamond briefcas have added security features, such as tamper-evident seals or coded numbers, to prevent unauthorized access or exchange of the diamond while in transit.
They offer a practical way to ensure that diamonds remain identifiable and protected from contamination or exposure to light.
Relation to Diamond Grading Reports:

In addition to serving as protective packaging, the diamond briefca often works in conjunction with the diamond’s certification report, which provides detailed information about the diamond’s cut, clarity, colour, and carat weight.
For diamonds certified by labs like DCLA, the briefca may include information about the diamond’s grade according to the laboratory’s assessment.

Diamond brilliance refers to the amount of white light that is reflected from a diamond. It is one of the most important qualities that contribute to a diamond’s overall sparkle and appeal. Brilliance is primarily determined by how well the diamond has been cut, as this affects how light enters, reflects, and exits the stone.

Key Factors Contributing to Diamond Brilliance:
Cut Quality:

The cut of the diamond plays a crucial role in determining its brilliance. The diamond must be cut with the correct proportions, angles, and symmetry to allow light to enter and reflect in a way that maximizes brilliance.
A well-cut diamond will have facets that act like mirrors, reflecting light back to the viewer’s eye, creating that characteristic sparkle. A poorly cut diamond, on the other hand, will allow light to escape from the sides or bottom, reducing its brilliance.
Proportions and Symmetry:

The proportions of a diamond, such as the depth, table size, and crown angle, directly affect how light travels through the stone. A diamond with ideal proportions will allow light to reflect optimally and produce maximum brilliance.
Symmetry ensures that all the facets are aligned properly, which helps in the even distribution of light reflections.
Clarity:

While clarity (the presence of inclusions or blemishes) does not directly affect a diamond’s brilliance, it can influence how well light is reflected. Inclusions can scatter light inside the diamond, reducing the intensity of reflections. Diamonds with higher clarity typically exhibit greater brilliance.
Colour:

A diamond’s colour can also affect its brilliance. Colourless diamonds (graded D to F on the GIA scale) tend to reflect light better and show more brilliance compared to diamonds with noticeable colour. However, diamonds with a slight tint (G to J) can still have good brilliance, especially when they are well-cut.
Light Performance:

Brilliance is a part of a diamond’s light performance, which also includes other effects like fire (the dispersion of light into colours) and scintillation (the sparkle seen when the diamond is moved). Brilliance refers specifically to the white light reflection from the diamond.
Environmental Lighting:

The environment in which a diamond is viewed also influences its perceived brilliance. Natural sunlight or strong artificial light can enhance a diamond’s sparkle, while dim lighting or poorly lit environments may make the diamond appear duller.
When viewed under different types of lighting, such as incandescent or fluorescent, the diamond’s brilliance may vary slightly, but the overall cut and quality will still play a significant role in how it performs in terms of sparkle.
Brilliance vs. Fire and Scintillation:
Fire refers to the dispersion of light into the colours of the rainbow, and scintillation is the flashes of light that occur when the diamond is moved. While these contribute to the overall visual appeal of a diamond, brilliance is focused solely on the white light that the diamond reflects.
All three factors—brilliance, fire, and scintillation—work together to give a diamond its characteristic sparkle, with brilliance being the most noticeable when the diamond is at rest.
How Brilliance is Measured:
Diamond grading labs like GIA (Gemological Institute of America) assess a diamond’s brilliance by examining how light interacts with the diamond’s facets.
Brilliance score is often a part of overall cut quality grading, but some advanced tools and technologies (like Ideal-Scope and Aset tools) can help buyers visually assess a diamond’s brilliance by simulating how it will reflect light in different conditions.

A bow tie in a diamond refers to a dark shadow or dark area that appears across the center of a diamond, typically seen in princess or marquise cut diamonds. This shadow resembles the shape of a bow tie, hence the name. The appearance of the bow tie is a result of how the diamond is cut and how light reflects and refracts within the stone.

Key Characteristics of a Bow Tie in Diamonds:
Causes of Bow Tie Effect:

The bow tie effect occurs when light is not able to pass through the center of the diamond evenly, creating a darker area. This is most commonly seen in diamonds with deep cuts or those with asymmetrical facets.
It is more prominent in certain shapes, such as:
Marquise cut: Due to its elongated shape, the bow tie effect can be very noticeable in marquise diamonds.
Princess cut: The square shape of a princess cut can also result in some dark areas in the center, resembling a bow tie.
Radiant cut: Similar to princess cuts, radiant diamonds can also show a bow tie, although less often.
Appearance:

The bow tie typically appears as a dark zone or shadow running diagonally across the diamond’s table. The size and intensity of the bow tie can vary depending on the diamond’s proportions and cut quality.
Some bow ties are subtle and barely noticeable, while others may be more prominent and affect the overall visual appeal of the diamond.
Impact on Value:

The presence of a bow tie can sometimes negatively impact the beauty of the diamond, as it detracts from its overall brilliance and sparkle. This is especially true if the bow tie is large or dark.
However, not all bow ties are viewed negatively. In some cases, they are seen as a natural characteristic of certain cuts, and diamonds with subtle bow ties may still be considered beautiful and valuable.
Cut Quality:

The presence of a bow tie is often related to the cut quality of the diamond. Diamonds with a poorly executed cut may have more pronounced bow ties, while diamonds with a well-proportioned cut may have minimal or no bow tie effect.
Ideal or excellent cut diamonds are less likely to have an obvious bow tie, as the angles and facets are designed to optimize light return and minimize shadows.
Bow Tie in Fancy Cuts:

In diamonds with fancy shapes (e.g., marquise, oval, or pear), the bow tie effect is more common, especially in shapes that are elongated or asymmetric. The cut quality plays a critical role in reducing or accentuating the bow tie.
How to Minimise the Bow Tie Effect:

When choosing a diamond with a shape prone to a bow tie (e.g., marquise or princess cut), it is important to ensure the diamond has a well-balanced cut. A diamond with correct proportions and a properly aligned facet structure is more likely to have a minimal bow tie effect.
Sometimes, choosing a slightly different shape can avoid the bow tie altogether, such as opting for a round brilliant cut, which typically has less chance of exhibiting the bow tie effect.

A blue diamond is one of the rarest and most sought-after types of coloured diamonds, known for its stunning blue hue. The unique colour of these diamonds is caused by the presence of the element boron in their crystal structure, which absorbs light in the yellow and red parts of the spectrum and allows the blue light to be reflected, giving the diamond its distinctive colour.

Key Characteristics of Blue Diamonds:
Colour:

The blue colour of these diamonds can range from pale blue to vivid blue, with the most highly prized stones being those that exhibit a deep, intense blue hue.
The colour is caused by boron impurities, which are present in trace amounts during the diamond’s formation. The boron atoms affect how light is absorbed and reflected, giving the diamond its blue appearance.
Grading:

Blue diamonds are graded based on their colour intensity and the absence of undesirable secondary hues, such as gray or green. The Gemological Institute of America (GIA) uses a grading scale for blue diamonds, ranging from faint blue to fancy vivid blue.
The more intense the blue colour and the less presence of secondary hues, the more valuable the blue diamond. “Fancy blue” is used to describe diamonds that exhibit strong to vivid blue colours, while those with a duller blue shade might be graded as fancy light blue.
Rarity and Value:

Blue diamonds are incredibly rare, and their value can be significantly higher than that of white diamonds due to their scarcity. The rarity is partly because the element boron is rare in nature and is only present in certain regions where diamonds are formed.
Blue diamonds also often exhibit greater brilliance due to the way they absorb and reflect light, making them highly prized in the luxury jewellery market.
Famous Blue Diamonds:

Some of the most famous blue diamonds in the world include:
The Hope Diamond: A historic blue diamond weighing 45.52 carats, known for its rich blue colour and dramatic history.
The Blue Moon Diamond: A 12.03-carat fancy vivid blue diamond, which set a record when it was sold at auction in 2015.
The Winston Blue Diamond: A 13.22-carat blue diamond, one of the most significant diamonds in the world.
The Ocean Blue Diamond: A vivid blue diamond sold for a substantial sum due to its intense colour.
Clarity:

While clarity (the absence of internal imperfections) is a significant factor in the value of any diamond, blue diamonds tend to have a lower emphasis on clarity when compared to the overall colour and rarity. Many blue diamonds may have minor inclusions or blemishes, but the overall intensity of colour often takes precedence.
However, higher-quality blue diamonds with fewer inclusions can still fetch higher prices, especially if they exhibit exceptional clarity alongside their stunning colour.
Treatments:

Some diamonds are artificially treated to enhance their blue colour, often using high-temperature or high-pressure treatments. These treated diamonds are generally more affordable than naturally occurring blue diamonds but are less valuable.
Natural blue diamonds are much rarer and more valuable because they acquire their colour naturally over millions of years of formation under specific geological conditions.
Investment and Collectability:

Due to their rarity and desirability, blue diamonds are often seen as a good investment. Their value can appreciate over time, especially those that have strong provenance or exceptional characteristics.
Collectors often seek blue diamonds due to their exclusivity, and they are often featured in high-profile jewellery auctions and collections.
Famous Mining Locations:

The most famous source of blue diamonds is the Argyle Mine in Australia, which produced some of the world’s most well-known blue diamonds before its closure in 2020. The Argyle mine was also the source of other rare coloured diamonds, such as pink and red diamonds.
South Africa, India, and Botswana are other notable sources of blue diamonds, though the supply of these stones is limited.
Cultural Significance:

Historically, blue diamonds have been associated with royalty, luxury, and status. Their rarity and captivating colour have made them highly coveted, with famous blue diamonds often passed down through royal families or sold at prestigious auctions.
In modern times, blue diamonds continue to be a symbol of elegance and refinement, often sought after by collectors and those looking for a distinctive and luxurious gem.