DCLA to Continue Full Grading of All Diamonds, Including Laboratory-Grown

The Diamond Certification Laboratory of Australia (DCLA) reaffirms its commitment to providing precise and comprehensive grading for all diamonds, including laboratory-grown stones. This approach ensures consistency, transparency, and informed decision-making across the industry.

While the GIA has announced it will introduce a simplified classification system for lab-grown diamonds — using the categories “Premium” and “Standard” — the DCLA will maintain its tradition of detailed grading across the full range of quality characteristics. This includes reporting actual colour, clarity, cut, and carat weight for every diamond submitted, regardless of its origin.

The GIA’s new system, expected later this year, will group lab-grown diamonds based on overall appearance and finish, with certificates including carat and cut details but without specific colour and clarity grades.

DCLA recognises that both natural and laboratory-grown diamonds hold unique value and significance. By continuing to offer full grading reports, the DCLA supports both the trade and consumers in understanding and appreciating the distinct qualities of each stone.

At DCLA, we believe that consumers and the trade deserve full and detailed grading information, regardless of the diamond’s origin. Misrepresentation and confusion are more likely to arise when simplified or vague grading systems are used — especially as laboratory-grown diamonds become more prevalent in the market.

As Australia’s official CIBJO laboratory, DCLA remains dedicated to upholding the highest international standards in diamond certification and grading.

Why Diamond Grades Can Differ Between Laboratories: Understanding Colour and Clarity Variations

The difference in diamond grading between laboratories like GIA (Gemological Institute of America) and DCLA (Diamond Certification Laboratory of Australia) can occur due to the subjective nature of diamond grading and variations in grading standards, tools, and methodology.

Here’s a detailed explanation of why this happens:

Example of a diamond graded GIA E VS2 vs DCLA F SI1:

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1. Grading is Subjective to Some Extent

Even though labs follow international grading systems like those defined by CIBJO or GIA, colour and clarity grading involves human judgment under magnification and controlled lighting conditions. Two experienced graders may interpret borderline characteristics differently.

• Colour: E and F are adjacent grades, and the difference is extremely subtle—often imperceptible to the untrained eye.
• Clarity: The distinction between VS2 (Very Slightly Included 2) and SI1 (Slightly Included 1) can also hinge on size, position, nature, and number of inclusions, which may be judged differently by separate labs.

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2. Different Lab Philosophies

• GIA is widely considered the global benchmark for consistency and tends to be more conservative in some grading aspects, especially in colour.
• DCLA, while highly respected and CIBJO-accredited (and Australia’s official diamond authority), might interpret certain characteristics differently based on their internal grading protocols.

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3. Grading Conditions and Equipment

Minor differences in:

• Lighting
• Magnification tools
• Grading environments
  can affect the appearance of a diamond, especially in borderline cases.

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4. Grading Date and Re-evaluation

Grading can differ if:

• The diamond was graded at different times.
• The diamond was repolished or slightly recut between submissions.
• The grader has different levels of training or experience (even within the same lab over time).

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5. Lab-to-Lab Variance Is a Known Industry Factor

Even among top labs (GIA, IGI, HRD, AGS, DCLA), 1-grade differences in colour or clarity are common and not considered errors. This is why many dealers and appraisers say a difference of one colour or clarity grade is within acceptable tolerance.

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In Your Example:

• GIA E VS2 vs DCLA F SI1:
  • The colour difference (E vs F): within acceptable tolerance; both are considered colourless.
  • The clarity difference (VS2 vs SI1): SI1 is a full grade lower, but this could be due to:
    • An inclusion judged more impactful by DCLA
    • A stricter application of clarity grading by DCLA
    • GIA possibly being more lenient on that particular clarity characteristic

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Differences like GIA E VS2 and DCLA F SI1 can result from:

• Subjective human interpretation
• Slightly different grading standards
• Borderline characteristics
• Environmental and technical grading factors

For buyers or sellers, it’s important to:

• Always compare certificates from top-tier labs.
• Understand that 1-grade discrepancies are common.
• Consider getting a professional review if there’s a significant value implication.

It is possible to trace a diamond

 

It is possible to trace a diamond if it has been reported as lost or stolen and has been registered with a diamond grading and identification laboratory. Many diamonds are laser-inscribed with a unique identification number or code that can be used to identify the stone if it is recovered.

In addition to laser-inscriptions, diamond grading and identification laboratories such as the Gemological Institute of America (GIA, the International Gemological Institute (IGI) and (DCLA) Diamond Certification Laboratory of Australia, provide certificates for diamonds that include a detailed description of the stone's characteristics, including its carat weight, colour, clarity, and cut. These certificates are the main method used to help identify a lost or stolen diamond.

However, it is important to note that not all diamonds are registered with these laboratories or have laser-inscriptions. Additionally, some diamonds may be recut or modified in a diamond cutting factory, making them more difficult to identify, But not impossible. Therefore, while it is possible to trace a lost or stolen diamond, it is not always guaranteed.

While measurements do provide all the proportion information about a diamond, they alone cannot be used to definitively identify a diamond.

Diamond measurements typically refer to the dimensions of the stone, including its length, width, and depth, as well as the angles and proportions of the diamond's cut. Measurements determine a diamond's shape and some aspects of its quality, such as its symmetry and polish, these alone do not provide enough information to identify a diamond conclusively.

To identify a diamond, experts will rely on a combination of factors, including the diamond's unique physical characteristics, such as its colour, clarity, and fluorescence, as well as any laser-inscriptions or certificates associated with the stone.

DCLA has a diamond registry, linking your diamond ownership 

 

Source: Certin Diamond insurance 

De Beers Eases Buyer Terms Amid Market Slowdown

 

De Beers will offer widened concessions to purchasers of larger rough diamonds at its upcoming sight as trading has slowed amid difficult market conditions.

The miner will increase its “buyback” allowance to 20% for 1-carat goods and up at the sale, which begins later this month, industry insiders told Rapaport News this week.

Buybacks are a mechanism enabling sightholders to sell 10% of stones back to De Beers after making their purchases. They are popular among clients when markets are weak, as customers can handpick the least profitable items and hope the miner will offer a good price. For De Beers, they provide a way of promoting sales without reducing prices.

Lockdowns in China and global economic uncertainty have spooked sections of the industry, with De Beers’ move reflecting a split in the market. Companies that usually buy 1-carat and larger rough destined for the Far East have reduced their purchasing, while top US and European brands continue to buy melee, supporting the trade in rough under 0.75 carats, dealers explained. In that context, the miner will maintain its usual 10% buyback allowance for rough under 1 carat.

“People actually did buy a lot [of the larger items] up till June [or] July this year, when they thought China would slowly start opening up again,” a market participant said. “That clearly hasn’t happened, and there are people now sitting on those goods.”

Sightholders are expecting De Beers’ next sales cycle — its ninth of the year — to bring the miner around $400 million after buybacks, compared with $500 million in September. The sight will run from October 31 to November 4. The December sight is also likely to be relatively small as southern African cutting factories shut for the holidays.

The October sight will take place amid the Diwali season in India, for which manufacturers are expected to implement extended production pauses of up to three weeks because of the sluggish market. Many of them have been trying to slash their inventories ahead of the holiday.

“De Beers is not too eager to reduce prices at this stage. I think they want to wait till early 2023 for that,” a sightholder predicted.

Source: DCLA