*This is an opinion piece. We have a position and we are going to argue it. The facts cited are accurate and sourced. The interpretation is ours, and we think it is the right one.*
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On the 2nd of June 2025, the Gemological Institute of America announced that it would no longer use its internationally recognised 4Cs grading system for laboratory-grown diamonds. Effective from the 1st of October 2025, any lab-grown diamond submitted to GIA would receive one of two verdicts — "Premium" or "Standard" — or be rejected outright. The specific colour grade, the specific clarity grade, the detailed cut assessment that buyers had relied on for decades: gone.
GIA called this a commitment to scientific integrity. The lab-grown diamond industry called it a betrayal. Most consumers did not hear about it at all, which may have been the point.
We think what happened on the 1st of October 2025 is one of the most consequential and least-discussed events in the history of lab-grown diamonds. And we think the GIA's stated reasons for making this change do not survive basic scrutiny. This is the piece we wish someone had published clearly and plainly in the weeks after the decision came into effect. Consider it a briefing from a brand that certifies every stone with IGI and has a direct stake in making sure you understand what a grading report is actually for.
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## The 4Cs: what they were and why they mattered
To understand what was taken away, you need to understand what the 4Cs provided.
Before GIA created the 4Cs grading system in the 1940s and 1950s, buying a diamond was an exercise in trusting the jeweller in front of you. There was no universal language for quality. "Fine colour" meant whatever the seller decided it meant. "Clean" was a verbal assurance, not a documented fact. The same stone could be described differently in different shops and there was no external standard to appeal to.
The 4Cs — Cut, Colour, Clarity, and Carat — changed this. By creating a precise, documented scale (D through Z for colour; Flawless through I3 for clarity; Excellent through Poor for cut), GIA gave buyers a language they could use independently of the seller. You could take a grading report and compare it against another grading report from another shop. You could understand exactly what a G-VS1 meant versus an H-SI1. You could make trade-offs — a buyer who understands that an F colour stone looks identical to a D colour stone to the naked eye can make an informed decision to choose the F and save money. The 4Cs gave consumers power over a market that had historically concentrated all information on the seller's side of the counter.
That is specifically and precisely what the GIA's new system for lab-grown diamonds has removed.
Under Premium/Standard, you know only whether the stone meets certain combined thresholds. Premium requires D colour and at least VVS clarity, with Excellent cut, polish and symmetry, for a round brilliant. Standard covers VS clarity and better, E to J colour, Very Good grades for cut and finish. Anything below Standard is rejected outright.
What you cannot know from a GIA Premium report: whether your stone is D, E, or F colour. Whether it is VVS1 or VVS2. Whether it has a particular inclusion characteristic that might matter to you. Whether the cut is optimised at the higher end of Excellent or just barely qualifying.
In other words, a GIA Premium report tells you that your stone met a threshold. An IGI report, which still uses the full 4Cs system for lab-grown diamonds, tells you exactly what your stone is.
The car comparison that has circulated widely online captures this well. The new GIA report tells you only that your car is "Fast." Is it a Ferrari or a Mustang? You have no idea. That is the new reality of GIA colour grades on lab-grown diamonds. Imagine trying to make a price comparison with only that information.
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## GIA's stated reason — and why it does not hold
GIA's Executive Vice President Tom Moses explained the change in June 2025: *"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."*
This statement is technically accurate. It is also deeply misleading in what it implies.
Yes, more than 95% of lab-grown diamonds fall into the D-to-J colour range and VS clarity or better. This is a consequence of CVD growth producing nitrogen-free Type IIa crystals by default — a fact we have explored at length elsewhere on this site. Lab-grown diamonds are, on average, significantly higher quality than the average natural diamond. The average natural diamond sold globally is in the G-H colour range and SI1-SI2 clarity. The average lab-grown diamond is closer to D-F colour and VS or better clarity.
The fact that lab-grown diamonds are consistently high quality is an argument *for* full grading, not against it. When 95% of stones are in a narrow high-quality band, the distinctions within that band become *more* important for buyers, not less.
Consider: if you know that almost all lab-grown diamonds are D to J and VS or better, then the difference between a D-colour stone and a J-colour stone within that range is approximately 9 colour grades — a range that spans from completely colourless to noticeably tinted. That difference absolutely matters. A D-colour diamond and a J-colour diamond are both within GIA's new "Standard" band if they meet the other criteria. Yet under the new system, they would receive the same certificate.
This is not simplification. It is the removal of information.
The Italian Gemological Review put it most bluntly: *certifying lab-grown diamonds is becoming less and less profitable for GIA, and GIA has long appeared uneasy with its role in this segment.* The publication noted that this marks GIA's third revision to its approach to grading synthetic stones in roughly two decades — suggesting not scientific clarity, but institutional ambivalence. GIA currently grades fewer than 5% of lab-grown diamonds, with the overwhelming majority certified by IGI. The economics of maintaining a full grading infrastructure for a market segment that is not using your services was, almost certainly, a factor in this decision.
The stated reason is market reality. The real reason, we believe, is a combination of economics and institutional alignment.
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## Who benefits from this decision — and who doesn't
GIA was founded in 1931 as a non-profit educational institution with a mission to protect the gem-buying public. Let that institutional identity sit alongside the following observation: every consequential effect of GIA's October 2025 decision benefits the natural diamond industry and harms lab-grown diamond buyers.
First: it removes information from buyers of lab-grown diamonds specifically, while leaving natural diamond grading entirely unchanged. If this were genuinely about the irrelevance of the 4Cs scale to highly uniform stones, you would expect GIA to at least acknowledge that the decision affects buyers differently than sellers. Instead, the GIA's own press material frames the decision as a return to founding principles of protecting public trust. Protecting buyers by giving them *less* information is a novel interpretation of consumer protection.
Second: it creates a visible institutional hierarchy. GIA grades natural diamonds with the full 4Cs. GIA grades lab-grown diamonds with two vague categories. The message to the market — not stated, but structurally embedded in the policy — is that natural diamonds deserve precision while lab-grown diamonds do not. The framing from GIA's own supporters in the natural diamond industry was explicit: as the Natural Diamond Council put it, GIA's decision *"demonstrates that natural diamonds continue to be the benchmark of authenticity, value, and irreplaceability."* GIA's change was immediately and successfully deployed as a marketing weapon by the organisation most financially invested in positioning natural diamonds above lab-grown ones.
Third: it creates confusion at precisely the point where clarity matters most — the purchase decision. Before October 2025, a buyer could compare a GIA lab-grown report and an IGI lab-grown report using the same language. Both said D, E, F for colour; both said VVS1, VVS2, VS1 for clarity. Now, a GIA Premium report and an IGI D-VVS1 report for the same stone cannot be directly compared by most buyers. This confusion benefits sellers who want to obscure quality differences, not buyers who want to understand them.
Amish Shah from ALTR, a leading lab-grown diamond producer, called the GIA move *"repositioning after failing to dominate market share,"* arguing that GIA's shift reflects their minimal presence in the lab diamond grading market rather than genuine quality concerns. That criticism is from inside the industry and should be read as self-interested — but it is also, on the substance, largely correct. GIA did not dominate the lab-grown certification market. IGI did, grading more than 60% of lab-grown diamonds globally and generating the majority of its certification revenue from lab-grown services. GIA's departure is a market exit dressed as a principled stand.
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## The historical pattern GIA does not want you to see
The June 2025 announcement was not GIA's first reversal on lab-grown diamonds. It was the third.
Between 2007 and 2019, GIA used general descriptive ranges for lab-grown diamonds — "near colourless," "VVS" — and avoided applying the same scale used for natural diamonds. At the time, lab-grown diamonds were seen largely as a threat to market integrity, and GIA's messaging emphasised a clear boundary between natural and synthetic.
In 2020, GIA reversed course entirely and adopted full 4Cs grading for lab-grown diamonds. This coincided with skyrocketing prices in the lab-grown segment and a surge in consumer interest. The market was growing, the revenue opportunity was real, and GIA wanted a presence in it.
In October 2025, GIA reversed again — retreating to simplified categories at precisely the moment when the lab-grown market's volume had grown so large that IGI's dominance was irreversible, and GIA's market share had shrunk to fewer than 5% of submissions. The timing is notable. GIA adopted full 4Cs grading when lab-grown diamonds were expensive and GIA certification carried a premium. GIA abandoned full grading when prices had fallen, IGI had captured the market, and certifying a ₹80,000 lab-grown diamond at premium prices no longer made economic sense.
This is not the behaviour of an institution protecting consumers. This is the behaviour of an institution managing its competitive position and institutional identity. GIA's identity is bound to natural diamonds — it was built on them, it derives its prestige from them, and its most financially significant clients are the natural diamond producers and retailers whose product positioning is threatened by the growth of the lab-grown segment. Expecting GIA to be a neutral arbiter of lab-grown diamond quality, given this institutional reality, was always somewhat optimistic.
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## The India dimension
For Indian buyers specifically, this matters in a way that most international coverage of the GIA decision misses.
India is not a peripheral player in the lab-grown diamond story. <cite index="56-1">The Indian lab-grown diamond market was estimated at USD 4.74 billion in 2025, supported by the country's large-scale diamond manufacturing ecosystem, export infrastructure, and increasing government-backed research initiatives for synthetic diamond technologies.</cite> Surat processes approximately 90% of the world's diamonds by volume, and India's lab-grown exports have grown explosively. In early 2026, lab-grown diamond exports from India surpassed natural diamonds in volume for the first time.
Within this context, IGI has a physical presence in India that GIA does not match. IGI expanded its capacity in Surat specifically to serve global demand for lab-grown certification and has been grading stones at scale for Indian producers and buyers. The GCAL by Sarine partnership, which expanded to Surat in 2024, offers another full-4Cs option for buyers who want comprehensive documentation.
The BIS standard IS 19469:2025, which we have covered separately, requires full disclosure of growth method at the point of sale in India. It does not specify which laboratory must certify a stone, which means that as of October 2025, an Indian buyer relying on a GIA certificate for a lab-grown diamond is now receiving materially less information than they would receive from an IGI certificate for the same stone — while the Indian regulatory framework continues to strengthen disclosure requirements in the buyer's favour.
The practical implication for any Indian buyer purchasing a lab-grown diamond: GIA Premium or Standard is not an adequate substitute for IGI full 4Cs documentation. It tells you less. It costs more per carat for the GIA service. And it does not give you the specific colour and clarity information you need to make a genuinely informed purchase decision or to establish the stone's quality for insurance, resale, or documentation purposes.
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## What the IGI certificate gives you that GIA no longer does
For a lab-grown diamond certified by IGI, your grading report provides the following:
**A specific colour grade** on the D-to-Z scale. This tells you precisely where your stone sits within the colourless range. The difference between D and G is visible under some lighting conditions. The difference between D and J is visible under most. You deserve to know which one you have.
**A specific clarity grade** on the Flawless-to-I3 scale. This tells you precisely what is inside your stone and at what magnification it becomes visible. VS1 and VS2 are different. VVS1 and VS2 are different. These differences affect the stone's appearance in some conditions and affect its documentation value significantly.
**A full cut assessment** for round brilliant stones, including cut, polish, and symmetry grades on the Excellent-to-Poor scale, plus proportions, table percentage, and depth percentage. For fancy shapes, polish and symmetry grades are provided.
**The growth method** — CVD or HPHT — as a specific disclosure, not implied by a quality band.
**Type classification** — most IGI reports for colourless CVD lab-grown diamonds will note Type IIa status in the comments, which is the single most important chemical classification for buyers concerned with optical purity or astrological quality assessment.
All of this is on a single document that is globally recognised, digitally verifiable, and specific enough to support insurance documentation, resale listing, or direct stone-to-stone comparison. It is the information a buyer needs.
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## Our position, stated plainly
We are a lab-grown diamond brand. We certify every stone with IGI. We are not a neutral party in this debate, and we are not going to pretend otherwise.
What we will say, as clearly as we know how to say it: the GIA decision of October 2025 was not primarily about scientific integrity or market reality. It was a strategic repositioning by an institution whose financial incentives, institutional identity, and major client relationships are all aligned with the natural diamond industry. It removed information from the buyer's side of the transaction at a moment when the natural diamond industry's most pressing competitive challenge is the growth of the lab-grown segment.
We are not accusing GIA of bad faith. We are saying that institutions, like people, act in ways that serve their interests, and that when an institution's decision happens to benefit its most important stakeholders while harming consumers in the category competing against those stakeholders, the stated reason for the decision deserves scrutiny.
The buyer of a lab-grown diamond in 2026 who relies on a GIA Premium or Standard report is operating with less information than they had a year ago. They cannot compare colour grades. They cannot compare clarity grades. They cannot make the specific quality trade-offs that the 4Cs system was specifically designed to enable.
The buyer of a lab-grown diamond in 2026 who relies on an IGI full 4Cs report has exactly the same information they had before October 2025. They know their stone's colour to the letter. They know its clarity to the grade. They know its cut, polish, and symmetry. They can compare it against any other IGI-certified stone on any dimension.
The choice between those two documents is not a matter of brand preference. It is a matter of how much information you deserve to have about a purchase that costs real money and will sit on your body or in your family's jewellery box for decades.
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## What this means going forward
The GIA decision is unlikely to be reversed. The institutional dynamics that produced it have not changed, and GIA has framed the reversal of its reversal as a principled return to its founding mission. It would require significant external pressure — from consumer bodies, from regulators, or from the market itself — to move GIA back toward full 4Cs grading for lab-grown stones.
What can change is buyer behaviour. And buyer behaviour, in the lab-grown diamond market, is where the real power currently lies.
The market for lab-grown diamonds is growing because buyers are increasingly informed. They understand that the stones are chemically identical to natural diamonds. They understand that the price difference is a consequence of production economics, not quality. They understand that the certification document is their protection against misrepresentation. If that same informed buyer population understands that GIA's certification for lab-grown stones now provides less information than IGI's, the market will adjust. Retailers who want to serve informed buyers will certify with IGI. Those who prefer less-informed buyers may find GIA's simplified system convenient for reasons that are not in the buyer's interest.
We know which kind of retailer we are. Every Zorii diamond is certified by IGI, with full 4Cs documentation, disclosed growth method, and type classification in the comments. The certificate comes with the stone, before you commit to purchase. We explain what every line on that certificate means. And we have no interest in a world where buyers have less information, because our product survives and thrives specifically when buyers understand exactly what they are getting.
The GIA made a decision in October 2025 that moved the lab-grown diamond market in the wrong direction for buyers. That direction can be corrected, one informed purchase at a time. Read your certificate. Know what it contains. And if it only says Premium or Standard, ask for something that tells you more.
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*Every Zorii diamond is certified by IGI with full 4Cs grading — specific colour grade, specific clarity grade, full cut assessment, growth method disclosure, and type classification. We believe you deserve to know exactly what you are buying.*
*Explore the Zorii collection at [zoriidiamonds.com](https://zoriidiamonds.com)*
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**Key facts referenced in this article:**
- GIA announced the change on 2 June 2025; it took effect 1 October 2025
- Premium requires D colour, VVS clarity or better, Excellent cut/polish/symmetry (round brilliants)
- Standard covers E-J colour, VS clarity or better, Very Good grades
- GIA currently certifies fewer than 5% of lab-grown diamonds globally
- IGI generates over 60% of its revenue from lab-grown diamond services
- More than 95% of lab-grown diamonds fall into D-J colour and VS or better clarity (per GIA's own data, cited by Tom Moses)
- GIA has changed its approach to lab-grown grading three times: 2007-2019 (descriptive ranges), 2020-2025 (full 4Cs), October 2025-present (Premium/Standard)
- BIS IS 19469:2025 requires growth method disclosure at point of sale in India (effective January 2026)
