The World Jewellery Confederation (CIBJO) is set to reverse a decision made in 2010 – and insist that non-natural diamonds are labelled as “synthetic”.
It says the terms “laboratory-grown” and “laboratory-created” should be removed from the Diamond Blue Book – the de facto standard for diamond terminology, grading and trade practices – and from all relevant ISO Standards.
In addition, the 4Cs grading system should be used only for natural diamonds (as the GIA is now doing).
Udi Sheintal (pictured), president of CIBJO’s Diamond Commission, said the original acceptance of lab grown terminology had been well-intentioned, but proved to be misplaced.
“At the time, we believed we were acknowledging a commercial reality and extending a constructive hand to a new segment of the industry,” he said, in a special report ahead of the 2025 CIBJO Congress in Paris at the end of October.
“We hoped for a spirit of cooperation, with shared standards, ethics and transparency.”
But he said many in the synthetic diamond sector — along with some grading laboratories and major retail chains – took advantage of that inclusive approach.
“In addition, the marketing narrative around synthetic diamonds has been aggressively shaped to position them as the more ethical, sustainable, and conflict-free choice, almost always without substantiation.”
He also called for greater transparency, requiring that all descriptions and marketing of synthetic diamonds reflect the reality of their origin: they are not grown or created in a “laboratory,” but rather are manufactured in industrial facilities through artificial processes.
Recently, the Dubai laboratory encountered four stones submitted for update services inscribed with fraudulent GIA report numbers. Inconsistent font styles and placement indicated the numbers were not authentic GIA inscriptions.
Table 1. Comparison of characteristics of submissions with counterfeit inscriptions and their accompanying GIA grading reports. A careful comparison of their quality characteristics confirmed that these were not the same diamonds as described in their accompanying reports. Although the diamonds were carefully selected to closely match the features listed on the original reports, several subtle differences in their color grades, measurements, and other characteristics were identified (table 1). Even more obvious were the spectral differences between the fraudulent and original stones. The difference in the one-phonon region of the Fourier-transform infrared absorption spectroscopy clearly revealed a discrepancy in the diamond types. The diamonds from the original reports were type Ia with aggregated nitrogen impurities, while these submitted stones were all type IIa, confirming they were, in fact, different stones.
On fraudulent diamonds 1 and 2, photoluminescence (PL) spectra produced by 514 nm laser excitation at liquid-nitrogen temperature showed that 637 nm peaks were greater than 575 nm peaks. The 575 and 637 nm peaks are emissions from the nitrogen vacancy center in its neutral [NV]0 and negative [NV]− charge states, respectively. The 575:637 nm emission ratio of intensities of less than 1 (D. Fisher and R.A. Spits, “Spectroscopic evidence of GE POL HPHT-treated natural type IIa diamonds,” Spring 2000 G&G, pp. 42–49), along with other PL features, indicated that fraudulent diamonds 1 and 2 with the counterfeit inscriptions were natural diamonds that had undergone high-pressure, high-temperature (HPHT) treatment for color improvements.
The visible/near-infrared (Vis-NIR) absorption spectrum for fraudulent diamond 3, on the other hand, showed a 737 nm peak, which corresponds to the unresolved silicon vacancy [SiV]– defect at 736.6/736.9 nm commonly seen in laboratory-grown diamonds using the chemical vapor deposition (CVD) growth method (P. Martineau et al., “Identification of synthetic diamond grown using chemical vapor deposition (CVD),” Spring 2004 G&G, pp. 2–25). The observation of such features led to the determination that this stone was CVD-grown and subjected to post-grown HPHT processing.
Further PL spectroscopy analysis on fraudulent diamonds 3 and 4 using 633 nm excitation confirmed the presence of the SiV– doublet feature on both diamonds. In alignment with the Vis-NIR and PL spectra, DiamondView images of these two fraudulent stones displayed clear striations with interruption layers indicative of CVD growth (figure 1). These patterns are consistent with the step-flow growth structure of CVD-grown diamond, which was also visible under the microscope using crossed polarizers and further supported their laboratory-grown origins. The other two fraudulent diamonds (1 and 2), however, showed a lack of such patterns and demonstrated natural-looking features, which confirmed them as HPHT-processed natural diamonds.
Figure 2. GIA’s standard procedure is to cross out the counterfeit inscription. Image by GIA staff. Figure 2. GIA’s standard procedure is to cross out the counterfeit inscription. Image by GIA staff. Considering all evidence, we concluded that two of the four stones were laboratory-grown diamonds, and the other two were HPHT-processed natural diamonds. All four diamonds were not the same natural diamonds as described in their accompanying GIA grading reports. In accordance with GIA procedures, the counterfeit inscriptions were crossed out (figure 2) and new report numbers were assigned. In addition, GIA inscribes “TREATED COLOR” on natural diamonds with post-treatment history and “LABORATORY-GROWN” along with a GIA report number and distinct GIA LG logo on laboratory-grown diamonds.
Deceptive practices have occurred previously in the trade; similar instances of diamonds with fraudulent inscriptions have been reported by GIA (e.g., Summer 2021 Lab Notes, pp. 150–152; Fall 2021 Lab Notes, pp. 258–259). Additionally, non-diamond materials, such as synthetic moissanite, with fraudulent GIA inscriptions have been submitted as diamonds to GIA (Fall 2020 Lab Notes, pp. 424–425; Fall 2022 Lab Notes, pp. 360–361). These cases highlight the importance of verifying inscription authenticity because a fraudulent inscription could be overlooked by simple visual examination. One possible solution is GIA’s Match iD, a device that compares a diamond’s inscription with its grading report in the GIA database.
GIA says the switch to grading lab grown diamonds simply as “premium” or “standard” will take on 1 October.
The lab announced an end to full 4Cs color and clarity reports in June, but did not say at the time when the change would take effect.
In a statement yesterday (26 August) it also laid out the criteria it will use to distinguish Premium lab growns from Standard. Diamond that don’t meet all the minimum criteria for Standard will not receive a GIA assessment.
Cut grade – Very Good (round brilliant cut diamonds only)
GIA will charge $15 per carat, with a minimum fee of $15. Evaluation fee for diamonds below the minimum criteria is $15.
“Using descriptive terms for the quality of laboratory-grown diamonds is appropriate as most fall into a very narrow range of color and clarity,” said Pritesh Patel, GIA president and CEO.
“Because of that, GIA will no longer use the nomenclature created for natural diamonds to describe what is a manufactured product.”
Meanwhile rival lab IGI (International Gemological Institute) insists it will carry on with 4Cs grading for lab growns “to prevent industry and consumer confusion”.
Belgium’s HRD lab says it will no longer grade lab grown diamonds.
It wants to create what it calls a “clear distinction between natural and synthetic diamonds”.
HRD, a subsidiary of the Antwerp World Diamond Centre (AWDC), says it is the first lab to stop lab grown certification, although it will still issue certificates for jewelry containing lab growns.
The move, announced yesterday (18 June) follows GIA’s decision earlier this month to grade lab growns only as “premium” or “standard”, without scores for color or clarity.
It further emphasizes the distinction between natural and lab grown diamonds.
“As of 2026, we will no longer issue quality certificates for loose synthetic diamonds intended for commercial use,” said Ellen Joncheere, CEO of HRD Antwerp.
“In limited cases, we will continue to analyze synthetic diamonds, but strictly for research purposes. Jewellery containing synthetic stones will still be eligible for certification.”
HRD started grading lab growns in 2013, albeit with fewer grades of color and clarity than natural diamonds. In 2019 it aligned lab growns with natural stones, a move that appeared to signal greater parity between the two sectors.
Karen Rentmeesters, CEO of parent company AWDC, said: “By becoming the first diamond lab in the world to take an explicit and exclusive stance in favour of natural diamonds, HRD Antwerp is sending a strong signal.
“A clear distinction between natural and synthetic diamonds is essential to strengthen consumer trust and help safeguard the future of natural diamonds.”
In a landmark decision that will reverberate through the global diamond industry, the Gemological Institute of America (GIA) the world’s foremost authority in gemology—has announced it will no longer use its internationally recognized 4Cs grading system for laboratory-grown diamonds. Instead, beginning later this year, lab-grown diamonds submitted to GIA will receive simplified descriptors—categorized broadly as either “premium” or “standard”—or no grade at all if the quality is subpar.
While GIA’s move to redefine lab grown diamond grading might sound like a simple nomenclature change, it’s much more than that. This move marks a definitive moment in the ongoing separation of natural diamonds from lab-grown diamonds. It confirms what many in the industry have long known: lab-grown diamonds are not the same as natural diamonds and should not be treated as such.
Why the 4Cs Is Essential for Natural Diamonds
GIA created the 4Cs—cut, color, clarity, and carat weight—as a rigorous system to help consumers understand the unique and complex qualities of natural diamonds. No two natural diamonds are exactly alike. They are rare geological miracles forged deep within the Earth over billions of years, each carrying a singular fingerprint from Mother Nature. A grading report for a natural diamond is essential because these stones exist along an immense spectrum of characteristics.
Meet the Expert
Grant Mobley is the Jewelry & Watch Editor of Only Natural Diamonds.
He is a GIA Diamonds Graduate.
He has over 17 years of jewelry industry experience, starting with growing up in his family’s retail jewelry stores.
An uncut lab grown diamond
Why GIA Is Changing the Way Lab Grown Diamonds Are Graded
Lab-grown diamonds, on the other hand, are man-made and mass-produced using high-pressure high-temperature (HPHT) or Chemical Vapor Deposition (CVD) processes. According to Tom Moses, GIA executive vice president and chief laboratory and research officer, “More than 95% of laboratory-grown diamonds entering the market fall into a very narrow range of color and clarity. Because of that, it is no longer relevant for GIA to describe man-made diamonds using the nomenclature created for the continuum of color and clarity of natural diamonds.”Why Lab Grown Diamond Grading Needs a Different System
By replacing detailed grading reports with broader descriptors, such as “premium” and “standard,” GIA is drawing a clear line in the sand. They are telling consumers that these are not the same products and they should not be evaluated in the same way. And coming from GIA—the trusted nonprofit organization that established global diamond grading standards in 1953—this statement couldn’t be more authoritative.
Natural Diamonds: Rarity, Value, and Geological Identity
To understand why this change to lab grown diamond grading matters, it’s essential to examine what drives the value of natural diamonds: rarity and identity. Each natural diamond is finite, with unique growth patterns, internal inclusions, and color subtleties shaped by millions or even billions of years underground. These one-of-a-kind gems are the original luxury product—not just beautiful but rare and no longer forming in nature. Lab-grown diamonds, conversely, can be created in virtually unlimited quantities and replicated in appearance with astonishing ease. There is no rarity. There is no geological story. There is no true investment potential.
Ring Courtesy of The Clear Cut
Why Clarity in Lab Grown Diamond Grading Matters for Consumers
This distinction has become increasingly blurred by confusing marketing language and unclear labeling practices. Some in the lab-grown diamond space have leaned on the unsubstantiated language of “sustainability” and “equality” in comparison to natural diamonds, despite offering a fundamentally different product. But consumers deserve transparency. They deserve to understand what they’re buying, what it’s worth, and what makes one stone different from another. That’s precisely why this change from GIA is so important.
It’s also a return to the Institute’s founding principles. GIA exists to protect the public trust in gems and jewelry. With this shift, the Institute is ensuring that consumers can make informed choices without being misled by false equivalencies. By stepping away from the 4Cs for lab-grown diamonds, GIA is reaffirming its commitment to scientific integrity and public transparency.
GIA Diamond Grading Report
Let me be clear: This is not about pitting one product against another. Lab-grown diamonds have their place in the market. But we must stop pretending they are interchangeable with natural diamonds. They are not heirlooms, they are not investments, and they are not rare.
GIA’s decision demonstrates that natural diamonds continue to be the benchmark of authenticity, value, and irreplaceability. They are not merely carbon crystals—they are ancient, unrepeatable creations of nature, each with a backstory written in geologic time.
As this policy rolls out in late 2025, expect other gem labs to follow suit. The line separating lab-created simulacra and natural geological masterpieces is being redrawn with bold ink—and GIA is holding the pen.
GIA says its Dubai and Hong Kong labs will accept larger stones for grading, in the wake of President Trump’s imposition of retaliatory tariffs on its trading partners.
Last week GIA said its US labs in New York and California would not accept submissions from overseas until confusion had been cleared up over the status of stones entering the country for grading rather than for sale.
In a statement on Monday (7 April) the world’s biggest grading lab said that because of tariff-related “logistical challenges” it was temporarily expanding services in Dubai and Hong Kong.
Dubai will now accept rough or polished diamonds (D-Z) up to 9.99-cts and Hong Kong will impose no size limit, until further notice.
Both labs previously had a 3.99-cts upper size limit. In addition, Hong Kong will now grade fancy color diamonds.
GIA is to close its lab in Ramat Gan, Israel, saying it is no longer “financially sustainable”.
The facility, which opened in August 2012, will close by the end of this year. Submissions will be sent to GIA labs elsewhere, with no additional shipping costs, the lab said in a press statement.
GIA was not able to say at this stage which other labs it would use (Dubai is the closest), or how much extra time that would take.
“Despite reductions in operating costs and reduced staffing through attrition, the laboratory is not financially sustainable,” said GIA, which grades the majority of the world’s polished diamonds.
“The GIA laboratory in Ramat Gan, Israel, will end operations by the end of 2024 due to changes in the global diamond industry that resulted in significant declines in submissions from local clients over the last several years.”
GIA closed its Antwerp lab in July 2022, citing “limited demand for services and financial performance that did not support continued operations”.
It also has labs in Bangkok, Hong Kong, Mumbai, Surat, Tokyo, Carlsbad, New York, Dubai, Gaborone and Johannesburg, according to its website.
From 17 November submissions to the Ramat Gan laboratory will be sent elsewhere. “GIA is working to establish a third-party process to accept submissions from walk-in clients in Ramat Gan for service in other GIA laboratories,” the lab said.
Since early 2022, the price of polished natural diamonds has fallen approximately 40% and the industry is being buffeted by negative economic headwinds, an excess of mine supply and too much stock in the cutting centres. However, there is one statistic that cannot be ignored: around 50% of Diamond Engagement Rings purchased in the United States now contain a Lab Grown Diamond (LGD). Is this just another cyclical downturn or are we in the middle of a major structural change?
Diamonds were once the preserve of royalty and the uber-wealthy, but the diamond market has evolved over the past 80 years into more of a mass market product with democratisation of the diamond consumer. Since the late 1970s most polished diamonds below 5 carats were priced against the 4 ‘C’s’ (carat, clarity, colour and cut), which led to standardised pricing in the form of polished diamond pricing lists. Up until the turn of the century these lists were primarily available in the wholesale market, but the arrival of internet pricing soon gave the consumer access to that same standardised pricing. In a world where everyone knows the price of everything, branding is the only differentiator. Without a differentiator, commoditised products end up selling for the lowest price.
It was why one of the questions that De Beers tried to answer when it changed its business model 25 years ago was: “How do you take a necessity (the diamond) priced like a commodity and market it as a luxury priced like a brand?”
Unfortunately, that question remains unanswered. The industry did create hundreds of so-called ‘brands’; origin, cut, settings, etc; the problem was that very few of them were real “brands”. If something does not sell at a premium, it’s not a brand, and most natural diamonds sell at a discount, yet the more that the industry was unable to achieve a premium, the more it becomes fixated with talking about the “product” when the luxury world has spent the last 25 years talking about “values”.
The challenge for most jewellers is not making a sale, it is making a reasonable margin. Ask a jeweller what they are selling and if they reply “VS1, G-H colour, loose polished, 1-caraters” then the most relevant word in their business will be “discounting”, because what they are selling is a commoditised version of “crystallised carbon.” There is no differentiator.
The LGD industry realised that to succeed it simply needed to persuade consumers that natural diamonds and LGDs were the same – “optically, physically and chemically”, but to also position them as “slightly cheaper”. They could then ride on the back of 80 years of De Beers diamond advertising differentiate themselves by claiming that LGDs were “conflict free”.
A larger “ethical” LGD for the same money as a natural diamond or pay less for the same size, created a money printing machine for everyone involved. And it’s no surprise that LGDs real success has been in the United States, because historically America has always been a “discount market”, and “larger for less” plays to that tune.
If all you want in a diamond is the sparkle, then they are in essence the same. Except there is a very real difference between the two, which is why some LGD executives insist on calling natural diamonds “earth mined” diamonds, because “natural” is exactly what differentiates them. The story of their age, rarity, origin; their social and economic contribution but above all, their “social purpose”. It was the failure of the natural diamond industry to tell that story which opened the door to LGDs.
When LGD production exploded, wholesale prices collapsed to around a 95% to 98% discount to their natural diamond equivalent. Prices vary according to quality, but anecdotal evidence suggests that today in the wholesale market, it is possible to buy a single polished LGD for $150 a carat, buy in volume and its possible to pay as low as $80 a carat.
Many retailers have also dropped their LGD prices, but by no means as far, and even pricing LGD at a 20-40% discount to their natural diamond equivalent can still leave a very significant margin. Pandora will sell you a 1-carat LGD ring for $1,950. Helzberg Jewellers (a Warren Buffet company) will sell you a similar LGD for $1,999. It’s very likely that some in the LGD industry are making a gross margin of 200%, some much more for a product that Signet Jewellers sensibly cautiones it customers “Their relative abundance may not ensure the value will hold over time”.
Whatever happens to future LGD retail prices, the category has got itself into the American consumer psyche and that won’t easily change, although there are also two sides to this story. I heard of a jeweller who was recently asked by a HNWI to make a replica of her 8-carat natural diamond ring so she could wear it travelling. The original ring cost $500,000 but he sourced an equivalent LGD for $5,000, and apparently she was absolutely thrilled with it. The question is, will she buy natural again? On the other hand, if in the future a consumer could buy (for example) a 2-carat LGD engagement ring for below $200, how pleased would their fiancé be to receive it – Walmart recently had a 2-carat LGD ring for sale for only $257. How romantic!
The US bridal market (size over quality) is dominated by larger, lower quality diamonds. Since similar sized LGDs are cheaper (or you get a much better quality LGD), either that market disappears, or demand only reappears aner prices have fallen sharply (already happened). It is also likely that LGDs will replace small, lower quality natural diamonds in fashion jewellery – as they may replace the smaller stones in high-end pieces of natural diamond jewellery. Diamond mining companies whose profitability rely on these categories of diamonds probably need to find a new value proposition, or their days may be numbered.
For those in the natural diamond industry who can adapt, there is huge potential. For those that don’t, as the saying goes, “Kodak never saw it coming either”.
Except Kodak did see it coming; they just didn’t know what to do about it. Kodak was killed off by digital photography which ironically, they invented, patented, but didn’t know how to exploit it, so they franchised the technology and made a fortune until their patents expired, and then went bust. Have LGDs done the same to natural diamonds? “No”, the opposite; their success is forcing a complacent industry to change. Have they changed the paradigm? “Completely”.
New Delhi: India’s lab-grown diamond industry is facing challenges such as significant fall in prices, eroding consumer interest and competition from imports, think tank Global Trade Research Initiative (GTRI) said Sunday, adding said that though India faces the issue of production overcapacity, it continues to import in large amounts and this issue needs deeper investigation.
To address these challenges, the government needs to take certain steps such as setting clear and consistent rules to standardize quality, certification, and market practices; issuing a Quality Control Order to check quality of imports; and investment in research and development to improve production processes, reduce costs, and enhance the quality of lab-grown diamonds.
As per the report, India’s lab-grown diamond industry is facing a major challenge, with prices falling by 65% in the past year to Rs 20,000 per carat from Rs 60,000 due to local overproduction and oversupply from abroad, which points to problems like overproduction, high imports, and lack of regulation. The number of units producing lab-grown diamonds in India has increased to 10,000 units, leading to over supply and tougher competition.
The industry lacks clear regulations checking such practices, making it hard to ensure quality. Lack of proper certification, and low trust market operations could slow down the industry’s growth, according to GTRI founder Ajay Srivastava.
He added that 98% of India’s imports of rough lab-grown diamonds come from Hong Kong (63.7% or $728.2 million) and the UAE (28.5% or $326 million).
In FY24, India imported rough lab-grown diamonds worth $1.14 billion and exported cut and polished ones worth $1.3 billion.
Natural diamonds cost around Rs 3.5 lakh per carat and this price drop is making it difficult for manufacturers to repay loans taken for purchasing lab-grown diamond making machines, putting them under financial strain, GTRI said.
GIA says it has expanded its new verification service – aimed at combating “cloned diamond” fraud – to all its labs.
The Report Confirmation Service was launched last month in New York to identify lab growns being submitted for regrading as natural diamonds.
GIA says the service is now available at all locations. It will accept walk-in and courier submissions, will turn around loose diamonds in as little as 15 minutes, and will, initially, make no charge.
The service is available for GIA-graded diamonds with and without inscriptions. An original GIA cert is helpful but not essential.
An increasing number of lab growns are being fraudulently submitted for re-grading. They are cut to match the specifications of natural diamonds that have already been graded and inscribed with either with a GIA number (genuine or fake).
“Combatting this fraud is vital to protecting the public and ensuring their confidence in gems and jewelry – this is GIA’s mission,” said GIA president and CEO Susan Jacques.