Lab Diamond Guide

Lab-Grown
The 7 C’s
The Science
Certification
FAQs

Lab-Grown Vs Mined

A new era of elegance

Welcome to a new era of elegance. Crafted in high-tech laboratories, our diamonds are designed for an ethical future.

Lab-grown diamonds are revolutionising the world of luxury and choosing them over mined diamonds is not just a trend, but a more informed and conscious choice.

It’s also a choice without compromise, because lab-grown diamonds are almost entirely devoid of impurities, and are graded to a superior quality.

Both lab-grown and mined diamonds have the same chemical composition, and are structurally and visually identical. Without the use of very specialised equipment, expert gemologists cannot tell them apart. Identical in sparkle, feel, and brilliance, lab-grown diamonds stand shoulder-to-shoulder with their mined counterparts.

Ethical elegance

Blood diamonds are still a reality. They’re sourced from conflict zones where their sale can contribute to violent conflicts and human rights issues. Workers in these areas often face difficult conditions, including forced and child labour. Lab-grown diamonds are cultivated in controlled environments, and offer an ethical alternative. Your choice has an impact.

Environmental harmony

Say goodbye to the environmental toll of diamond mining. Lab-grown diamonds leave no scars on the Earth, requiring no deforestation and no pollution of water supplies. Meticulously-crafted, they shine as bright symbols of responsible luxury that can be worn every day.

Affordability redefined

Lab diamonds offer a cost-effective alternative to mined diamonds, delivering the same quality and sparkle at a fraction of the price. Elevate your style without compromising your value and wallet.

Limitless customisation

Embrace the freedom of expression with lab-grown diamonds. Their unique creation process allows for greater design flexibility, ensuring your jewellery is as distinctive as your personality.

Transparency and Certification

Trust in transparency. All our lab-grown diamonds above 0.5 carats come with GIA or IGI certification, providing clarity and authenticity. Your purchase is backed by verifiable quality.

We invite you to explore a world where elegance meets ethics, where luxury can be enjoyed every day, and where your choice reflects a commitment to a brighter, more sustainable future.

There is no longer a need to mine diamonds!

The 7 C’s

Astrea acknowledges the 7 C’s

Cut

The cut of a diamond refers to how well a diamond’s facets interact with light, which determines its brilliance and sparkle. Beyond the certificate’s cut grade, our gemologists recommend a closer review by an expert. Opt for ideal cut diamonds with excellent polish, symmetry, a depth percentage between 59-62%, and a table percentage between 54-60% for the ultimate sparkle.

Colour

Diamonds exhibit a spectrum of colour from D (colourless), to Z (light yellow), followed by fancy colours. A gemologist’s opinion is essential in evaluating the best colour for your diamond, as subtle distinctions significantly impact the quality and price.

Clarity

Clarity gauges imperfections or inclusions within the diamond. The GIA Diamond Clarity Scale ranges from Flawless (no inclusions visible under 10x magnification), to Included (inclusions obvious under 10x magnification). Expert assessment is crucial, as tiny inclusions may affect transparency and brilliance.

Carat Weight

Diamond weights are expressed in carats and decimals, with larger carat weights generally commanding higher prices. Consider carat weight alongside Colour, Clarity, and Cut for a comprehensive understanding of your diamond’s value.

Certification

Your personal certificate will validate the diamond’s authenticity, quality, and ethical sourcing of the stone. We provide certification from the two most respected institutions; the Gemological Institute of America (GIA) and the International Gemological Institute (IGI).

Conscience

Lab diamonds, created in a controlled and tightly-regulated environment, do not cause ecological disruption to any land surfaces or have any long-term effect on pollution, wildlife or social effects. Lab diamonds are the conscious choice, giving you the confidence that you’re purchasing a diamond that is both ethically and environmentally sound.

Cost

Consumers can purchase high-quality certified lab diamonds at a fraction of the price of similar mined diamonds (with exactly the same traditional 4C characteristics).

The Science

The state-of-the-art technology behind lab diamonds

At the intersection of innovation and nature, lab-grown diamonds are meticulously-crafted in controlled laboratory environments through one of two processes – High Pressure High Temperature (HPHT) or Chemical Vapour Deposition (CVD).

How are lab-grown diamonds created?

At the heart of the process lies a tiny ‘seed’, a small fragment of a authentic diamond. Our manufacturers expose this seed to carbon atoms under high pressure and extreme heat, mimicking the natural volcanic forces that created diamonds millions of years ago. Over two to four weeks, carbon atoms delicately crystallise on the seed’s surface, forming a rough, genuine diamond.

The High-Pressure High Temperature (HPHT) process

Originating in the 1950s for industrial use, HPHT mirrors the Earth’s interior conditions, creating diamonds within 2-4 weeks, as opposed to mined diamonds developing over billions of years. Techniques like the split beer (BARS) press, cubic press, and belt press create the high-pressure, high-temperature environment needed for a seed enveloped in carbon to meld and crystallise into a full-sized diamond.

Chemical Vapour Deposition (CVD)

CVD is a process that simulates the forming of diamonds in interstellar gas clouds. Firstly, a diamond seed is heated, then immersed in carbon-rich gases like hydrogen and methane, before cutting-edge plasma technology merges carbon layers onto the seed, growing your diamond with precision.

Developed in the 1980s, CVD stands out for its efficiency, using less energy than HPHT and offering a more cost-effective approach to diamond creation.

At Astrea, we do not believe that one method is better than the other, nor that there is a difference. What matters is the final product and the true quality of the stone.

Transparency & Certification

Trust in Traceability

Lab grown diamonds are crafted in high tech laboratories and can be traced right back to their origin so that you can be 100%confident your diamonds are conflict free and ethically produced. At Astrea, we invite you to explore a world where elegance meets ethics, where luxury can be enjoyed every day, and where your choice reflects a commitment to a brighter, sustainable future for our planet and our children.

The Sparkle

A diamond’s true sparkle is an elusive magic that goes beyond the certificate. Only a physical inspection by our experts can reveal the nuances in Cut, Polish, and Symmetry that make some diamonds shine brighter than others.

Inclusions

Our gemologist experts meticulously examine each diamond, ensuring no imperfections or undisclosed inclusions compromise its beauty. We guarantee you will receive a flawless gem that stands the test of scrutiny.

Girdle

While the certificate details the girdle, judging the quality of a fancy-shaped diamond requires more than just paperwork. Physical inspections unveil the true size and perfection of a diamond’s girdle – a factor crucial to its overall allure. Your perfect diamond deserves a hands-on assessment.

Colour Shade

Lab-grown diamonds, if not grown perfectly, might reveal subtle hues unseen by machines. Our experts, however, catch these nuances, ensuring the true colour of your diamond shines through, identifying and preserving the authentic essence that impacts your diamond’s value.

Fancy-Shaped Diamonds

Certificates for fancy-shaped diamonds lack cut grades, leaving a crucial aspect uncharted.Our experts will assess the cut quality, especially for fancy diamonds, ensuring every facet meets the highest standards of brilliance.

Ratio of the Diamond

The industry’s set standards for each shape, like the ratio for an oval, can impact a diamond’s appearance. A perfect ratio ensures you get the visual impact you desire. Our specialists will check this vital element physically, so you never pay for a 2-carat diamond that looks like 1.50 carats.

We believe that true value and quality goes beyond the certificate. Our expert gemologists physically inspect each diamond, ensuring that your chosen stones are only of the highest quality and sparkle.

FAQs

The 7 C’s are a comprehensive guide in the diamond industry, representing crucial factors that influence a diamond’s quality and value.

1. Carat Weight:

Carat weight is a measure of a diamond’s weight and size, determining its brilliance and rarity.

Carat Weight image

2. Cut:

The cut of a diamond refers to how well a diamond’s facets interact with light, which determines its brilliance and sparkle. All of our lab diamonds are an ideal or excellent cut,which reflects almost all of the light that enters it and emits the most sparkle.

cut image

3. Colour:

Diamonds come in various colours, and the absence of colour is highly valued. Graded on a scale from D (colourless) to Z (light yellow or brown).

colour image

“We look to inspire the entire diamond industry to evolve in a brave new direction”.


4. Clarity:

Clarity assesses the presence of natural imperfections or inclusions within a diamond. The fewer the imperfections, the higher the clarity grade.

Clarity image

5. Certification:

Certification ensures that your diamond meets industry standards and provides an unbiased evaluation. Our experts recommend that you only purchase diamonds that are certified by GIA or IGI, the two most reputable gemological grading institutions.


6. Cost:

Lab-grown diamonds are proving to be significantly more affordable than mined diamonds. However, it is also important to consider how each of a diamond’s graded characteristics contributes to its overall cost.


7. Conscience (Ethical and Sustainable consideration):

Lab-grown diamonds are ethically-sourced and conflict-free. Ensure your diamond has a clean, traceable origin, free from ties to violence, human rights abuses, or environmental harm.

Each of the 7 C’s plays a role in determining the perfect diamond for you. Whether you prioritise size, brilliance, or ethical considerations, understanding these factors empowers you to make a more informed and meaningful choice.

What are the 7 C's?

The 7 C’s are a comprehensive guide in the diamond industry, representing crucial factors that influence a diamond’s quality and value.

1. Carat Weight:

Carat weight is a measure of a diamond’s weight and size, determining its brilliance and rarity.

Carat Weight

2. Cut:

The cut of a diamond refers to how well a diamond’s facets interact with light, which determines its brilliance and sparkle. All of our lab diamonds are an ideal or excellent cut,which reflects almost all of the light that enters it and emits the most sparkle.

Cut

3. Colour:

Diamonds come in various colours, and the absence of colour is highly valued. Graded on a scale from D (colourless) to Z (light yellow or brown).

Colour

“We look to inspire the entire diamond industry to evolve in a brave new direction”.

4. Clarity:

Clarity assesses the presence of natural imperfections or inclusions within a diamond. The fewer the imperfections, the higher the clarity grade.

Clarity

5. Certification:

Certification ensures that your diamond meets industry standards and provides an unbiased evaluation. Our experts recommend that you only purchase diamonds that are certified by GIA or IGI, the two most reputable gemological grading institutions.

6. Cost:

Lab-grown diamonds are proving to be significantly more affordable than mined diamonds. However, it is also important to consider how each of a diamond’s graded characteristics contributes to its overall cost.

7. Conscience (Ethical and Sustainable consideration):

Lab-grown diamonds are ethically-sourced and conflict-free. Ensure your diamond has a clean, traceable origin, free from ties to violence, human rights abuses, or environmental harm.

Each of the 7 C’s plays a role in determining the perfect diamond for you. Whether you prioritise size, brilliance, or ethical considerations, understanding these factors empowers you to make a more informed and meaningful choice.

What are the different shapes of Diamonds?
Round Brilliant image

The Round Brilliant Shape Diamond

is the most popular of all the diamond shapes. The Round Brilliant is cut with 58 facets, allowing light to be reflected throughout the stone. Due to the way it’s cut, it sparkles more than any of the other diamonds. Inclusions are not as visible in the Round brilliant Shape like they are with some of the other stones.

Oval image

Oval Shaped Diamonds

are quite brilliant. However, like the Pear Shaped Diamonds, caution is needed when purchasing to make sure that there are no “bow-ties” (grey triangular reflections) inside the stone. Small bow-ties are fine, but larger bow-ties will cause a large grey patch in the stone, detracting its sparkle. It is important to look at the length-to-width ratio of the oval shape, making sure that the stone is not too skinny and long, or too short and wide.

Radiant image

Radiant Shape Diamonds

are either square or rectangular with slanted corners. Radiant Shaped Diamonds have more durability against chips, which is great for those who are rough with their jewellery. The Radiant Shape Diamond has the second most brilliance after the Round.

Emerald image

Emerald Shape Diamonds

Diamonds do not have much brilliance, and hold their colour really well. They are quite “see-through”, allowing one to look into the facets where stone inclusions may be visible to the naked eye. To make sure that the Emerald Shape looks nice, it is important to look at the length-to-width ratio, making sure that the stone is not too skinny and long, or too short and wide.

Pear image

Pear Shape Diamonds

are quite brilliant. However, caution is needed when purchasing to make sure that there are no “bow-ties” (grey triangular reflections) inside the stone. Small bow-ties are fine, but larger bow-ties will cause a large grey patch in the stone, detracting its sparkle. It is important to look at the length-to-width ratio of the Pear Shape Diamond, as a stone that is too skinny and long, or a stone that is too short and wide, would not.

Cushion image

The Cushion Shape Diamond

has become quite popular in recent years. Cushion Shape can be rectangular or square. Neither of those is better than the other, it is just personal preference. The Cushion Shape appears to be a mix of a square and round stone.

Princess image

The Princess Shape Diamond

is a square-cut diamond. Due to the corners being at 90 degrees, they must be protected by decent claws when set into a ring. Princess Shaped Diamonds are well priced as they do not have much wastage when cut from a rough diamond.

Asscher image

Asscher Shape Diamond

was created by Joseph Asscher in the early 1900s. The Asscher Shape Diamond has a similar appearance to an Emerald Cut Diamond, with the main difference being that it is square with slanted corners.

Marquise image

The Marquise Shape Diamond

is a popular diamond shape characterised by its elongated, boat-shaped outline with pointed ends. The marquise cut is known for its elegant and distinctive appearance, and it can make a diamond appear larger than other cuts of the same carat weight.

Heart image

The Heart Shape Diamond

is a romantic and distinctive diamond shape that is characterised by its resemblance to a heart, making it a symbol of love and affection. It’s a unique and eye-catching choice for engagement rings and other jewellery.

How are lab diamonds made?

Unlike the time it takes to unearth mined diamonds, lab/nurtured-grown diamonds typically take less than a month to grow in a controlled laboratory environment, through state of art technology simulating the Earth’s natural processes. Scientists replicate the mined diamond formation process and the natural conditions using renewable energy. These high-tech manufacturers expose a tiny shard of a diamond, called a “diamond seed”, similar to a mined diamond. The cut and polishing of both mined and lab diamonds is done with exactly the same process and expert craftsmanship.

There are two main procedures commonly used to create lab-grown diamonds:

​High Pressure High Temperature (HPHT)

Due to the extreme temperature and pressures involved, this process could be likened to natural diamond formation.

Chemical Vapour Disposition (CVD)

The CVD method relies on carbon-based gases with high temperature and low pressure. This technology mimics how the universe uses plasma to create stars and planets.

How do I choose between HPHT and CVD Lab Diamonds?

We do not believe that one method is better than the other, nor that there is a difference. What matters is the final product and the true quality of the stone, which is determined by our gemologists’ assessment and the IGI/GIA certification.

  • Both CVD and HPHT technologies can create diamonds of any colour, clarity, and size.
  • All our supply is Type II, the most chemically pure diamonds available.
  • Both methods can produce D colours, VVSL1, and FL diamonds.
  • HPHT generally yields higher colour, while CVD tends to produce higher clarities.
  • Most diamonds under 1ct are usually HPHT for cost-effectiveness.
  • Between 1 – 2.5/3 carats, the market supplies both CVD and HPHT equally.
  • For diamonds above 2.5/3 carats, CVD is more common, resulting in larger stones.

Even diamonds with the same certified characteristics can differ in appearance, and therefore it is key for a gemologist to physically assess each diamond to ensure you get the best quality.

What are the different diamond types?

Diamonds can be of differing types based on chemical impurities. This significantly impacts their purity and other characteristics.

Type II (a and b) diamonds are the purest, with negligible impurities. Type IIb diamonds contain Boron elements, and emit a blue or grey tone associated with fancy blue diamonds. All lab diamonds are Type II, with CVD diamonds produced as

Type IIa. 98-99% of the world’s mined diamonds are Type 1 and have more impurities, lower hardness, and carbon purity compared to Type II.

We exclusively select Type II lab diamonds, aligning with the top 1-2% of natural diamonds in the market.

Certification of Lab diamonds

We recommend that all diamonds purchased, whether lab or mined, should be certified by one of the two most trusted diamond certifiers, namely GIA (Gemological Institute of America) and IGI (International Gemological Institute). We will ensure all our diamonds above 0.25 carats will be certified by one of these two companies.

Certificates from other institutions can be questionable, particularly as grading styles can differ between companies, resulting in quality variations. Experts grading the colour and clarity of the diamonds have always trusted GIA and IGI for their grading, as both companies have maintained their grading standards and have the best technology. As a result, their reputation remains strong in the market.

When lab diamonds are produced (anywhere in the world) circa 80-90% goes through Surat (India) to be cut and polished by gem experts, and receive certification. All our certified lab-grown diamonds are laser inscribed, giving you peace of mind that your diamond will have an easily-identifiable, unique number.

IGI has been certifying lab diamonds since 2015, using the same standards as mined diamonds. GIA, despite grading lab diamonds since 2007, only began recognising lab diamonds as ‘non synthetic’ in 2021 when they started certifying them with the same standards as mined diamonds. As a result, IGI certifies approximately 90% of lab diamonds today. Further to this, jewellery can also be certified separately, once the diamonds are set within the pieces by an independent company (like the World Gemological Institute – WGI).

IGI certificates state whether a lab diamond is grown with either the CVD or the HPHT process. They also mention whether the diamond is type IIa (for CVD) or type 2 (for HPHT).

Why could there be variations in lab diamond quality?
  1. Different machines produce different diamond qualities.
  2. Investment in Technology: Regular updates to reactors and materials are essential to maintain high-quality diamond production.
  3. Seed Quality Matters: The initial seed quality significantly defines the overall diamond quality.
  4. A diamond is as good as the cut and polish it is given. Differences in the cut and polish can affect the quality of the diamond and therefore the price.

At Astrea, we address these differences by sourcing diamonds exclusively from the finest manufacturers with rigorous processes. All our diamonds undergo further assessment by our expert gemologists.

Are Lab-grown diamonds sustainable and environmentally friendly?

Diamond mines often require clearing large areas of land, involving significant deforestation, pollution of local water supplies and destruction of local ecosystems.

The network of diamond mines, and the pollution created as a result, is environmentally harmful and contributes little to local economies. Diamond mines could otherwise be exploited as valuable land resources, which could be used for more sustainable purposes, such as farming.

Lab diamonds, created in a controlled and tightly-regulated environment, have a far less harmful impact to the environment than mined diamonds. They do not cause ecological disruption to any land surfaces, and have no long-term effect on pollution, wildlife or social effects. Lab stones are partly created with renewable energy, and leave behind minimal emissions, resulting in little-to-no harm to our planet and society. Lab diamonds also do not require water, unlike mined diamonds.

Frost & Sullivan conducted a benchmark study comparing the environmental impact of mined and lab diamonds. Assessing impacts on a common scale, their ratio indicator revealed a staggering difference. To provide a comprehensive overview, they allocated weights using the Analytic Hierarchy Process (AHP) framework, emphasising the substantial environmental advantage of lab diamonds.

For instance, air emissions for 1 carat of mined diamond were 1.5 billion times higher than for a lab diamond. The study also showed, on an indicative basis, that mined diamonds represented more than 7 times the level of impact compared to mined diamonds.

Are Lab-grown diamonds sustainable and environmentally friendly image
Are Lab-grown diamonds ethical?

Lab diamond production does not involve human rights violations, such as forced, unsafe or even child labour, that is often associated with mining diamonds. As a result, by purchasing a lab diamond, you will never have to worry about purchasing an unethical stone or a “blood diamond”. Blood diamonds, also known as “Conflict diamonds”, are gemstones mined in territories controlled by rebel forces opposed to internationally recognised governments. The rebels sell these diamonds and use the proceeds to buy weapons or to support military operations. By contrast, lab diamonds are ethically sourced.

What should I consider when buying a lab diamond?

When purchasing a lab diamond, it’s crucial to:

Beware of Simulants: Some companies may use terms like “simulants” for diamonds made from materials like cubic zirconia or moissanite. These are easily distinguishable with the naked eye, unlike lab or mined diamonds.

Check for Gemologist Inspection: Ensure that online companies have gemologists physically checking lab diamonds before selling them.

Verify Certificates: Stick to reputable institutions like IGI and GIA for certification. Be cautious of certificates from other sources.

Understand Inclusions: Recognise that most diamonds, whether lab-grown or mined, may have inclusions. Mined diamonds often have noticeable impurities and minerals, HPHT lab diamonds may have metallic flux inclusions, and CVD lab diamonds may have polycrystalline inclusions. However, it’s essential to note that inclusions in lab diamonds are generally less visible to the naked eye compared to mined diamonds.

Is my shipment insured?

Yes, your jewellery is fully insured by us whilst in transit, to the point when you receive it.

Can I insure my lab grown diamond ring and jewellery?

Yes, it works the same way as with any diamonds or jewellery you have.

What is your warranty?

All our diamonds are certified by IGI or GIA confirming their characteristics and grading. Astrea jewellery (excluding the diamonds which is certified as above) comes with a 30-day warranty which covers all repairs and servicing free of charge in the unlikely event of a manufacturing fault or defect.

How long does it take to receive my jewellery?

For some of our ready-made jewellery, we need 1-2 weeks. However, please allow 4 to 6 weeks for our bespoke, made to order jewellery. Some jewellery will be quicker, some might take a bit longer.

What is the process for purchasing bespoke jewellery with Astrea?

The first stage is to discuss your intended design with us so that we can estimate the cost and send you an invoice. Upon receipt of the invoice, we ask for a 50% deposit to complete the designs for your piece of jewellery and source the best diamonds for production.

Within 2-4 weeks, we’ll send you a video of your completed piece (checked by our gemologist experts who will send you a video for final approval). We deliver worldwide with full insurance. You can settle the final 50% when you collect directly from us or before it’s shipped. We accept payment by bank transfer or any payment card, including AMEX.