Diamond anatomy

Carat weight is a measurement used to quantify the size of a diamond and is one of the four key factors that determine a diamond’s overall value, commonly referred to as the “4C’s” along with cut, colour, and clarity.

One carat is equivalent to 0.2 grams, and diamonds are typically weighed to the hundredth of a carat to provide precise measurements. Therefore, a 1.25-carat diamond weighs 1 carat and 25 points.

Larger diamonds generally have a higher carat weight and are often considered more valuable. However, the overall value of a diamond is also influenced by its cut, colour, and clarity.

It’s essential to note that carat weight alone does not necessarily determine a diamond’s beauty or brilliance. The cut of the diamond, which refers to its proportions and facets, plays a crucial role in how well it reflects light.

Diamond prices tend to increase exponentially with carat weight due to the rarity of larger stones. However, individual preferences and the overall balance of the 4 C’s should be considered when selecting a diamond, ensuring a well-rounded and visually appealing choice.

Diamonds are graded on a colour scale ranging from D (colourless) to Z (light yellow or brown). The closer a diamond is to the colourless end of the spectrum, the more valuable it is considered.

Some rare diamonds, known as fancy colour diamonds, exhibit colours beyond the traditional scale, such as blue, pink, or yellow. These diamonds are valued for their unique and intense hues.

Colour grading is typically done under controlled lighting conditions, and even subtle variations in colour can significantly impact a diamond’s appearance and value. When selecting a diamond, personal preferences, budget, and the desired setting should all be considered in conjunction with the diamond’s colour grade.

Diamond clarity refers to the presence of imperfections, known as inclusions, within the stone. Gemmologist use a magnification factor of 10x to assess and grade these flaws, determining the diamond’s clarity grade.

Diamonds are categorized on a clarity scale, ranging from Flawless (no visible inclusions or blemishes under 10x magnification) to Included (inclusions visible to the naked eye). Each clarity grade represents a different level of purity and transparency in the diamond.

Clarity significantly influences a diamond’s brilliance and sparkle. Stones with higher clarity grades tend to have better light performance, as fewer inclusions allow light to pass through and reflect with minimal obstruction.

The nature, size, and location of inclusions play a vital role in determining a diamond’s clarity. Some inclusions may be internal, while others are external blemishes, and their impact on the overall appearance varies.

At Van Deijl we adhere to strict guidelines regarding the nature of inclusions when choosing diamonds to minimize the negative effect thereof. For example, all the diamonds we supply will strictly be eye-clean (showing no inclusions visible to the naked eye). With no black inclusions, knots, cavities, twinning whisps, bruises or indented naturals in the diamonds.

At Van Deijl Jewellers, we prioritize the quality of diamond cuts, recognizing this stage as
pivotal where human craftsmanship can elevate or detract from the diamond’s inherent
beauty. We only choose diamonds with Excellent cut grades within very precise proportions
to maximize the light yield of the stone. As technology in diamond cutting has advanced over
the years, we have continually refined these proportions, leading to the creation of the VDJ
Excellent and VDJ Superior ranges. Diamonds that fall in our VDJ Cut parameters are
exceptionally bright with exemplary fire bringing the diamond’s true beauty to life.

Diamonds, although a natural occurrence, are exceptionally scarce compared to other minerals.

It is believed that diamonds form at depths ranging from 150 km to 200 km beneath the Earth’s surface, where conditions of high temperatures (1050°C – 1200°C) and pressures (45 kilobars – 55 kilobars) facilitate their crystallization.

Subsequently, these diamonds may be carried upward by hot molten rock (magma) as it intrudes into the Earth’s crust, creating narrow cylindrical bodies known as ‘pipes’, with only a small fraction containing significant diamond content.

These kimberlite pipes are known as cratons and represent some of the oldest parts of the Earth’s crust.

When these pipes undergo erosion, released diamonds can accumulate in alluvial deposits. One of the most significant sources of alluvial diamonds is the Orange River in the Northern Cape province of South Africa. The area is known as the “Alluvial Diamond Fields” this region has been a significant source of alluvial diamonds for many years. The diamonds in this deposit were transported by the Orange River from the Kimberley region and eventually deposited in the alluvial plains and riverbeds. The river’s action sorted and concentrated the diamonds, making it a significant area for diamond mining. Due to their hardness, diamonds can be found far from their original source, enduring multiple episodes of erosion and deposition.

Diamond quality is broadly categorized into gem, near gem, industrial, and boart classifications. Some deposits may consist of up to 90% gem-quality diamonds although most economically viable deposits only contain between 20% and 40% gem-quality material.

In the diamond processing journey, more than 50% of a rough diamond is typically lost during cutting and polishing, and this figure can rise to 80% if the diamond is flawed or misshapen. Fancy cut diamonds tend to yield more from the rough stone than the standard round brilliant leading to this loss reflecting in the price of the stone.

While the Earth’s crust predominantly consists of the relatively common element carbon, constituting 99.95% of its composition, the transformation into a natural diamond demands extreme conditions. These conditions, characterized by exceptionally high temperatures and pressures, occur deep beneath the Earth’s surface.

Given that most diamond mines are situated in remote areas, factors such as mining costs and the overall profitability of a diamond mine contribute to the rarity of diamonds. Diamonds are a rarity, with most mines yielding merely 0.5ct to 2ct of gem-quality rough for every ton of ore processed.

Despite the prevalence and affordability of smaller diamonds, larger, high-quality stones with exceptional colour, clarity, and precise cut proportions are exceedingly scarce. Due to larger high-quality rough being so scarce many diamond cutters tend to focus on retaining carat weight of the stone rather than focusing on the cut of the stone. Resulting in many 1ct stones to appear bigger or smaller than what they weigh (diameter for an excellent cut 1ct stone should be 6.5mm).

To extract a single 1.00ct D Flawless diamond, approximately 100,000 tons of ore may need processing.

Finding a VDJ Excellent or Superior cut diamond in today’s market is a formidable task, as less than 10% of all diamonds, regardless of colour and clarity, meet our VDJ Excellent cut parameters. Diamonds in our strictest VDJ Superior cutting parameters represents 1% of all round brilliant cut diamonds in the market.

The scarcity of such diamonds significantly influences their market price, ensuring that properly cut diamonds of this calibre retain most of its value over time.

Lab-grown diamonds have the same chemical composition as natural diamonds. They are composed of carbon atoms arranged in a crystal structure, which gives them the same hardness and brilliance as natural diamonds.

Lab-grown diamonds are either created through a Chemical Vapor Deposition (CVD) process or High Pressure-High Temperature (HPHT) process.

In the CVD method, a combination of methane (to provide the carbon), hydrogen, oxygen and argon gas, are passed through a microwave which heats the gases to create a plasma. Atoms of carbon are deposited on seed plates to build a diamond crystal.

In the HPHT method, which mimics the natural conditions for diamond formation in the Earth’s mantle, the BARS apparatus is a widely employed system. Utilizing eight pistons, it shapes the reaction cell into an octahedron within a split sphere subjected to significant hydraulic pressure. This configuration replicates growing conditions in the mantle of the earth. Sustaining mantle conditions, sustaining temperatures of 1350–1600°C and pressures of 50–80 Kbar for diamond synthesis.

The market for lab-grown diamonds has been growing rapidly in recent years. As awareness of their availability and affordability increases, more consumers are choosing lab-grown diamonds for their engagement rings, jewellery, and other applications. Major jewellery retailers and designers are also starting to offer lab-grown diamonds alongside natural diamonds, reflecting the increasing acceptance of lab-grown diamonds in the industry.

Like their natural counterpart, lab grown diamonds are available in a wide range of sizes, shapes, and qualities. They are graded using the same standards as natural diamonds based on the 4Cs: cut, colour, clarity, and carat weight.

While lab-grown diamonds are believed to have a lower environmental impact compared to mined diamonds, it’s important to acknowledge that they are not without negative environmental considerations. Here are some potential negative environmental impacts associated with lab-grown diamonds:

Energy Consumption: The production of lab-grown diamonds requires significant energy inputs, particularly in the high-pressure, high-temperature (HPHT) and chemical vapor deposition (CVD) processes used to create them. If the energy used is sourced from non-renewable or fossil fuel-based sources, it can contribute to greenhouse gas emissions and climate change.

Chemical Usage and Waste Generation: Certain chemicals and gases are used in the production of lab-grown diamonds, including methane, hydrogen, and various carbon-containing gases. While many manufacturers have implemented strict safety protocols and waste management systems to minimize environmental contamination, improper handling or disposal of these chemicals could potentially lead to pollution of air, water, or soil.

Water Usage: Although lab-grown diamonds generally require less water compared to mined diamonds, water may still be used in some stages of the production process, such as cooling equipment or washing surfaces. In regions where water resources are scarce or already stressed, this water usage could contribute to local environmental impacts, such as competition for water resources or strain on ecosystems.

Resource Extraction: While lab-grown diamonds do not involve the physical extraction of natural resources from the earth like mined diamonds, they do require the extraction and processing of raw materials such as carbon sources, metal catalysts, and other materials used in manufacturing equipment. The extraction of these resources may have environmental consequences, including habitat destruction, energy consumption, and pollution associated with mining and processing operations.

Overall, while lab-grown diamonds seem to offer several environmental benefits compared to mined diamonds, such as reduced land disruption, lower carbon emissions, and minimized water usage. It’s important to recognize that they are not without environmental impact. Continued research, innovation, and adoption of sustainable practices are necessary to mitigate these negative impacts and ensure that lab-grown diamonds contribute to a more environmentally responsible jewelry industry. While certain companies are transparent about their environmental impacts, companies in South and Eastern Asia, which are the largest producers of lab-grown diamonds, tend to be less forthcoming in this regard.