Posted on

Clarity

SI1: Inclusions are noticeable under 10x magnification, but not always visible to the naked eye.

Diamond clarity refers to the presence and visibility of inclusions (internal flaws) and blemishes (external flaws) within or on the surface of a diamond. The clarity of a diamond significantly affects its overall appearance, brilliance, and value.

Diamond Clarity Grading Scale
The Gemological Institute of America (GIA), one of the most respected grading authorities, uses a clarity scale to evaluate diamonds. The scale ranges from Flawless (FL) to Included (I3). The GIA clarity scale includes the following grades:

Flawless (FL)

No internal or external imperfections visible under 10x magnification.
The highest clarity grade and extremely rare.
Internally Flawless (IF)

No internal inclusions, but there may be minor surface blemishes visible under 10x magnification.
Very rare and highly valuable.
Very, Very Slightly Included (VVS1 and VVS2)

VVS1: Inclusions are extremely difficult to detect under 10x magnification.
VVS2: Inclusions are still very difficult to detect but may be visible to a skilled grader.
These diamonds have excellent clarity, and their inclusions are barely perceptible.
Very Slightly Included (VS1 and VS2)

VS1: Inclusions are difficult to detect under 10x magnification.
VS2: Inclusions are easier to see under magnification but still difficult for the untrained eye.
These diamonds are high quality and commonly found in fine jewellery.
Slightly Included (SI1 and SI2)

SI1: Inclusions are noticeable under 10x magnification, but not always visible to the naked eye.
SI2: Inclusions are visible under magnification and may be visible to the naked eye in some diamonds.
These diamonds are more affordable, but clarity is still relatively good.
Included (I1, I2, and I3)

I1: Inclusions are obvious under magnification and may be visible to the naked eye.
I2: Inclusions are easily visible and affect the diamond’s transparency and brilliance.
I3: Inclusions are highly visible and can affect the durability of the diamond.
Diamonds in this category are generally lower in value due to the impact of visible inclusions.
Factors Influencing Diamond Clarity
Size, Number, and Location of Inclusions: Larger or numerous inclusions generally lower the clarity grade. Inclusions near the centre of the diamond (table) are more impactful than those near the edges.
Type of Inclusions: Some inclusions, like feathers (small cracks) or carbon spots (small black dots), may be more noticeable than others.
Visibility: Whether inclusions are visible to the naked eye or only under magnification significantly affects the clarity grade.
Clarity and Diamond Value
Higher Clarity: Diamonds with higher clarity grades (like FL, IF, and VVS) tend to be rarer and more expensive.
Lower Clarity: Diamonds with lower clarity (such as SI and I grades) are more affordable, though they may have visible inclusions.
Clarity vs. Other Cs
While clarity is important, it is only one of the 4Cs that determine a diamond’s overall quality. Cut and colour are often more influential on a diamond’s brilliance and aesthetic appeal than clarity, especially when the inclusions are small or well-placed.

Posted on

Clarity Enhancement

Clarity enhancement in diamond

Clarity enhancement in diamonds refers to the process of improving the appearance of a diamond by reducing the visibility of inclusions and blemishes. This is often done to diamonds with lower clarity grades to increase their marketability and value. However, it is important to note that clarity-enhanced diamonds can be priced differently from untreated diamonds, and the enhancement methods can affect their long-term durability and appearance.

Common Clarity Enhancement Techniques:
Laser Drilling

This process is used to remove dark inclusions, such as black carbon spots or feathers (small cracks), by creating a small hole through the diamond to the inclusion.
A laser beam is used to vaporize the inclusion, making it less visible.
Pros: This method can significantly improve the diamond’s clarity by removing visible inclusions.
Cons: The laser drilling process can leave a small tunnel or cavity in the diamond, which may affect its structural integrity and can be visible under magnification.
Fracture Filling (Laser-Enhanced or HPHT)

This method involves filling cracks or fractures (feathers) with a special glass-like substance or a material that is similar in appearance to the diamond itself.
The filler improves the clarity of the diamond by making the inclusion less noticeable.
Pros: It can improve the diamond’s appearance by making cracks and fractures blend with the diamond, especially for diamonds with I clarity grades.
Cons: Fracture-filled diamonds can be more prone to damage, as the filler material can be less durable than the diamond itself. It is also detectable by trained gemologists under magnification.
High Pressure High Temperature (HPHT) Treatment

This method is mainly used on diamonds with a brown or yellowish tint, but it can also be applied to enhance clarity.
It involves subjecting the diamond to extremely high pressure and temperature conditions, which can cause some inclusions (especially graining or carbon spots) to be less noticeable.
Pros: It is an effective way to reduce the appearance of certain inclusions and may improve the overall colour and clarity of the diamond.
Cons: HPHT treatment can cause certain inclusions to become more prominent over time, and the process is not always fully reversible.
Implications of Clarity Enhancement:
Impact on Value:

Clarity-enhanced diamonds are generally priced lower than untreated diamonds of the same carat weight, cut, and colour.
The enhancement can improve the diamond’s marketability, but it is important for buyers to understand that the treatment affects the diamond’s long-term value.
Disclosure and Transparency:

Ethical practices in the diamond industry require disclosure of any clarity enhancements, as these treatments can affect the diamond’s value and durability.
Gemological laboratories such as GIA and DCLA will include information on any clarity enhancements in the diamond’s grading report. It’s important for buyers to request this information when purchasing a diamond.
Durability:

Depending on the type of enhancement, the durability of the diamond may be impacted. For example, a fracture-filled diamond may be more susceptible to damage because the filling material is not as hard as the diamond.
It is recommended to be cautious when cleaning or setting clarity-enhanced diamonds, as the treatments can weaken the stone.
Resale and Investment Considerations:

Clarity-enhanced diamonds may not retain their value as well as untreated diamonds in the secondary market. Their resale value can be lower because of the treatments applied.
Should You Consider Clarity Enhancement?
Clarity-enhanced diamonds can be an affordable option for those looking to get a larger or more visually appealing diamond without the higher price tag of an untreated high-clarity stone.
However, it’s essential to weigh the potential downsides, including the risk of damage and reduced long-term value.

Posted on

Chameleon-Type Diamond

Chameleon-Type Diamond

Key Characteristics of Chameleon Diamonds:
Colour Change:

Chameleon diamonds typically shift from an olive green or grayish-green hue to a yellow or orangey-yellow shade when exposed to heat (approximately 150°C) or left in darkness for an extended period.
Once cooled or exposed to light again, they revert to their original colour.
Thermochromic & Photochromic Properties:

The colour change can occur due to both heat (thermochromism) and darkness/light exposure (photochromism), making them unique among diamonds.
Rare Chemical Composition:

Scientists believe the colour change is due to a combination of hydrogen, nitrogen, and possibly nickel impurities within the diamond’s crystal structure.
Not a Fancy Colour Diamond:

Unlike standard fancy colour diamonds, which have a fixed hue, chameleon diamonds possess a dynamic, temporary colour change.
Value & Rarity:

Due to their scarcity, chameleon diamonds are highly prized by collectors and diamond enthusiasts.

Unlike standard fancy colour diamonds, which have a fixed hue, chameleon diamonds possess a dynamic, temporary colour change.

Value & Rarity:

Due to their scarcity, chameleon diamonds are highly prized by collectors and diamond enthusiasts.

Posted on

Champagne Diamond

Champagne Diamonds: A Unique Fancy-Coloured Diamond
A champagne diamond is a type of fancy-coloured diamond that exhibits a warm brown hue with subtle golden or yellow undertones, resembling the colour of champagne. These diamonds are prized for their unique earthy tones and affordability compared to traditional white diamonds.

Key Characteristics of Champagne Diamonds
Colour Range

Champagne diamonds range from light golden brown to deep cognac shades.
The colour intensity is determined by the presence of nitrogen in the diamond’s structure.
The Argyle Mine in Australia (now closed) famously produced some of the world’s finest champagne diamonds.
Grading & Classification
Unlike white diamonds, which are graded on the D-Z colour scale, champagne diamonds are classified based on their intensity:

C1 – C2: Light champagne
C3 – C4: Medium champagne
C5 – C6: Dark champagne
C7: Deep brown (also called Cognac Diamond)
Cut & Shape

Champagne diamonds are cut in various shapes, with round, oval, cushion, and pear cuts being popular.
A well-cut champagne diamond enhances its brilliance and highlights its warm tones.
Rarity & Value

While not as rare as pink or blue diamonds, high-quality champagne diamonds with strong brilliance and even colour distribution are highly sought after.
They are generally more affordable than traditional colourless diamonds, making them an attractive alternative.
Symbolism & Popularity

Champagne diamonds symbolize elegance, warmth, and individuality.
They are increasingly popular in engagement rings and bespoke jewellery due to their distinct and sophisticated look.

Posted on

Chip

A chipped diamond refers to a diamond that has sustained a small break or loss of material from its surface, typically at the edges or corners. Chipping is generally caused by impact or rough handling. While it may not affect the diamond’s overall structure, it can influence its appearance, value, and durability.

Key Points About Chipped Diamonds:
Causes of Chipping:

Impact: Diamonds are very hard but not immune to damage, especially if they experience a sudden blow or fall onto a hard surface.
Sharp Edges: Diamonds with sharper corners or thinner edges, such as those found in princess cuts or emerald cuts, are more prone to chipping.
Improper Setting: A diamond set in a way that leaves its edges exposed is at higher risk of chipping.
Impact on Value and Appearance:

Clarity: A chipped diamond may have a noticeable blemish that lowers its clarity grade. It can reduce the diamond’s brilliance, as light may not reflect as effectively from the damaged area.
Aesthetic: A chip is visible to the naked eye in most cases, especially if it’s located near the centre or on a large diamond.
Value: Chipped diamonds are typically worth less than those without damage. The degree of value loss depends on the size and location of the chip.
Repair Options:

Re-cutting: For diamonds with significant chips, a jeweler can re-cut the diamond to remove the damaged area, potentially enhancing the diamond’s overall appearance. However, this reduces the diamond’s carat weight.
Polishing: Small chips can sometimes be smoothed or polished to reduce visibility, though this may not completely eliminate the blemish.
Re-setting: If the chip is near the edge, a jeweler may also re-set the diamond in a protective setting, such as a bezel, to prevent further damage.
Prevention:

Careful Handling: To prevent chipping, diamonds should be handled carefully, especially if set in rings or worn frequently.
Secure Setting: Settings that protect the edges of the diamond, such as bezel or tension settings, can prevent damage.
Checking for Chips:

It’s essential to regularly inspect your diamond for any signs of damage, especially after a fall or impact. A professional inspection can also reveal chips that may not be easily noticeable with the naked eye.

Posted on

Cavity

Cavity

A cavity is a type of diamond inclusion that appears as an opening or large indentation on the surface of a diamond. It occurs when a small part of the diamond is removed, often due to the detachment of another inclusion (such as a crystal or feather) during the cutting or polishing process.

Key Characteristics of Cavity Inclusions in Diamonds:
How Cavities Form

They usually form when a weak area of the diamond, such as an internal inclusion, falls out during cutting, polishing, or wear.
Can also result from the removal of a feather (crack) or crystal inclusion.
Impact on Diamond Quality & Value

Visibility: Cavities can be noticeable, especially if they are large or located in a prominent position.
Durability Concern: A deep cavity can make a diamond more vulnerable to chipping or further damage over time.
Clarity Grade Reduction: Diamonds with significant cavities may receive a lower clarity grade from the GIA (Gemological Institute of America).
Where Cavities Are Found

They can appear anywhere on the diamond, but those near the edges or girdle are less concerning than those in the center (table).
How to Minimize the Effect of Cavities

Strategic Setting: A prong or bezel setting can hide a cavity located near the edge.
Polishing & Recutting: If the cavity is shallow, a jeweler may be able to polish or recut the diamond to remove or reduce its appearance.
Avoiding Further Damage: Regular cleaning and careful handling can help prevent dirt from accumulating inside the cavity, which can make it more visible.

Posted on

Certificate

Diamond Certificate or Diamond Report
A diamond certificate, also known as a diamond grading report, is an official document issued by a gemological laboratory that provides an objective assessment of a diamond’s quality. It evaluates key characteristics such as carat weight, cut, colour, clarity, and other essential factors.

What a Diamond Certificate Includes:
A diamond grading report typically contains:

Carat Weight – The precise weight of the diamond in carats (ct).
Cut Grade – Evaluates how well the diamond is cut, affecting its brilliance and fire.
Colour Grade – Ranges from D (colourless) to Z (light yellow or brown).
Clarity Grade – Assesses internal inclusions and external blemishes, from Flawless (FL) to Included (I3).
Shape & Measurements – Specifies the diamond’s shape (e.g., round, oval) and dimensions in millimeters.
Fluorescence – Indicates if the diamond glows under UV light, which may impact its appearance.
Symmetry & Polish – Evaluates the precision of the diamond’s cut and surface quality.
Inclusion Plot (Clarity Map) – A diagram showing the locations of inclusions and blemishes.
Security Features – Some certificates include laser inscription of the report number on the diamond’s girdle for verification.
Recognised Diamond Certification Laboratories
Reputable gemological laboratories that provide independent, accurate, and unbiased diamond grading include:

GIA (Gemological Institute of America) – The most respected and widely recognised grading authority worldwide.
AGS (American Gem Society) – Known for its strict grading standards, particularly for cut quality.
HRD (Hoge Raad voor Diamant) – A leading European gem lab based in Antwerp, Belgium.
IGI (International Gemological Institute) – Commonly used in the retail diamond market.
EGL (European Gemological Laboratory) – Offers looser grading standards compared to GIA and AGS.
DCLA (Diamond Certification Laboratory of Australia) – The only independent diamond grading laboratory in Australia, known for its strict and accurate grading.

Posted on

Carbon

Carbon

Diamonds are made of pure carbon, but their unique atomic structure is what gives them their remarkable properties.

Why Diamonds Are Special:
Pure Carbon Composition

Diamonds are composed entirely of carbon atoms (C) arranged in a crystal lattice structure.
Unlike other carbon-based materials like graphite or coal, diamonds have a tetrahedral atomic arrangement, making them the hardest naturally occurring substance.
Crystal Structure: The Secret to Hardness

Each carbon atom in a diamond forms strong covalent bonds with four other carbon atoms in a three-dimensional network.
This cubic crystal structure (known as a diamond cubic lattice) gives diamonds their exceptional hardness and durability.
Difference from Graphite

Both diamond and graphite are made of pure carbon, but they have different atomic structures (allotropes):
Diamond: Carbon atoms are arranged in a rigid 3D tetrahedral network → Hard and transparent
Graphite: Carbon atoms are arranged in stacked layers of hexagonal sheets → Soft and opaque
This difference in structure explains why diamond is used in cutting tools while graphite is used in pencils.
Formation Process

Natural diamonds form under high temperature (1,000–1,300°C) and extreme pressure (45–60 kbar) deep within the Earth’s mantle over 1–3 billion years.
Lab-grown diamonds are created using HPHT (High Pressure High Temperature) or CVD (Chemical Vapor Deposition) methods, replicating these natural conditions.
Purity and Impurities

A pure diamond consists only of carbon, but trace elements (e.g., nitrogen, boron) can cause variations in colour:
Nitrogen → Yellow diamonds
Boron → Blue diamonds
Radiation exposure → Green diamonds

Posted on

Carbon Spots

Small black graphite inclusions in a diamond.

Small black graphite inclusions in a diamond are a type of natural impurity that occurs during the diamond’s formation process. These inclusions can affect the diamond’s clarity, appearance, and value.

Key Facts About Black Graphite Inclusions in Diamonds:
What Are They?

Black inclusions are tiny particles of graphite or other carbon-based minerals trapped inside the diamond during its crystallization.
They appear as small black spots, specks, or clusters within the stone.
Impact on Clarity & Value

Diamonds with large, visible graphite inclusions receive lower clarity grades from the GIA (Gemological Institute of America).
If the inclusions are numerous or positioned near the surface, they can reduce transparency and brilliance.
However, some graphite inclusions are microscopic and do not impact the stone’s beauty significantly.
Types of Graphite Inclusions

Pinpoints – Tiny black dots only visible under magnification.
Clouds – Groups of small inclusions that create a hazy effect.
Needles or Veins – Thin, elongated graphite inclusions.
Carbon Spots – Larger black inclusions visible to the naked eye.
Are They a Problem?

If inclusions are small and well-placed (e.g., near the edges), they may not significantly affect the diamond’s beauty.
However, large or centrally located inclusions can impact transparency, sparkle, and durability.
How to Minimize Their Appearance

Cut Quality Matters – A well-cut diamond with a brilliant faceting pattern (e.g., round brilliant) can hide inclusions.
Setting Choice – Prongs and bezels can mask inclusions near the edges.
Clarity Enhancement – Some diamonds undergo laser drilling or fracture filling to reduce the visibility of black inclusions.

Posted on

Carat

Key Facts About Carat Weight:
Definition

One carat is equal to 200 milligrams (0.2 grams).
It is subdivided into 100 points, meaning a 0.50-carat diamond is also called a 50-point diamond.
Origin of the Term

The term “carat” comes from the carob seed, which was historically used as a reference for weighing gemstones due to its uniform weight.
Carat vs. Size

While carat refers to weight, it does not always indicate a diamond’s physical size.
Different cuts and shapes can make a diamond appear larger or smaller than another of the same weight.
Impact on Price

Diamond prices increase significantly with carat weight, especially at milestone sizes (e.g., 0.50 ct, 1.00 ct, 1.50 ct, 2.00 ct).
Larger diamonds are rarer and more expensive per carat than smaller ones.
Carat Weight vs. Other Cs

A diamond’s cut, colour, and clarity also play a major role in its overall value and appearance.
A well-cut 0.90-carat diamond can appear nearly the same size as a 1.00-carat diamond but at a lower cost.