CIBJO Retires Laboratory Grown

The World Jewellery Confederation (CIBJO) intends to strike the terms "laboratory grown" and "laboratory created" from its Blue Book at its congress on September 4. In their place, a single permitted descriptor: "synthetic."

From September 2026, "synthetic" will be the only term sanctioned by CIBJO for "artificial products having essentially the same chemical composition, physical properties and structure as that of their naturally occurring counterparts."

The decision followed a year of deliberation. CIBJO's conclusion was blunt: neither retired term actually "described the products to which they had been applied." By contrast, the confederation judged "synthetic" to be unambiguously clear in a gemmological context.

Charles Abouchar, head of CIBJO's colored-stone commission, framed the rationale in consumer-protection terms:

Crucially, this is not an isolated act. It lands as the latest — and arguably most consequential — entry in a rapid sequence of terminology decisions across the natural-diamond world.

Read in isolation, CIBJO's move looks like a standards body tidying its glossary. Read in sequence, it looks like an industry-wide realignment that has been building for roughly eighteen months.

Four separate categories of actor — a gemmological laboratory, a national standards bureau, a producer-country association, and a sovereign government — arrived at materially the same conclusion within a year of one another. CIBJO, as the confederation that publishes the Blue Book, is the piece that turns a pattern into something closer to a global default.

The Blue Book is not legislation. It has no enforcement arm and levies no penalties. But it functions as the trade's reference grammar: national trade bodies, laboratories, auction houses, insurers, and regulators cite it when drafting their own rules and disclosure requirements. A change to the Blue Book propagates outward through borrowing rather than through compulsion — which is slower, but tends to be more durable.

CIBJO's stated reasoning is definitional. "Laboratory grown" and "laboratory created," it argues, fail as descriptions. There is a real technical point buried in this: a substantial share of these stones are produced in industrial reactor facilities, not laboratories in any recognizable sense. "Grown" imports a biological metaphor — the vocabulary of cultivation, of something natural unfolding — onto what is fundamentally a manufacturing process. "Created," meanwhile, carries a faint aura of authorship and craft.

"Synthetic," by contrast, is precise, established in gemmological literature, and carries no such connotation. It says exactly what the product is: synthesized.

That is the linguistic case, and it is coherent. But nobody in the trade is under any illusion that the stakes are purely lexical.

In consumer-facing English, "synthetic" reads as artificial, substitute, lesser. Synthetic fabric versus natural fibre. Synthetic vanilla versus vanilla bean. The word carries a downward valence that "laboratory grown" — with its overtones of science, precision, and modernity — simply does not.

This is precisely why the terminology has been contested for years:

Both positions have merit. The lab-grown industry's technical point is sound: identical composition, identical structure, identical physical properties. CIBJO's own definition concedes exactly this — it defines "synthetic" as covering products with essentially the same chemical composition, physical properties and structure as their natural counterparts. The definition is not disputing the science.

What the definition does is relocate the emphasis from equivalence to origin. That is the substance of the change.

Of all the measures in the sequence, the Russian regulation is the most aggressive, and the detail that matters most is the unit.

Requiring lab-grown diamonds in jewelry to be declared in grams rather than carats does something the word "synthetic" alone cannot: it severs the shared measurement language between natural and synthetic stones.

The carat is not merely a unit of mass. It is the trade's pricing grammar, the axis of every price list, the number a consumer has been trained over a century to read as a proxy for value. A "1.5 carat diamond" is an instantly legible value claim. "0.3 grams" is not. It is a weight — technically accurate, commercially inert, and impossible to slot into a familiar mental price ladder.

This is regulatory design working at the level of consumer cognition rather than consumer knowledge. It does not require the buyer to understand anything new; it simply removes the comparability that made cross-category price anchoring possible in the first place.

Whether other jurisdictions adopt the gram requirement is one of the more consequential open questions in this whole file. Terminology alone is a labelling change. Terminology plus a different unit of measure is a structural separation of the two categories.

Straightforwardly advantaged. The core commercial argument of the natural sector has always been that rarity, geological origin, and finite supply constitute the value proposition — and that this argument only functions if consumers can clearly distinguish the two products. Terminology that reinforces the distinction reinforces the pitch.

The ADPA's participation is notable here: African producer nations have direct sovereign and employment interests in natural diamond demand, and their alignment adds producer-country legitimacy to what might otherwise be dismissed as marketing.

Materially disadvantaged, and likely to contest it. The lab-grown sector has built consumer-facing brand equity substantially on the language of "grown" — a vocabulary of technological progress, ethical sourcing, and environmental improvement. "Synthetic" is not a neutral substitute for that; it is a rhetorical downgrade.

Practical exposure includes:

Expect vigorous argument that the change is prejudicial rather than descriptive, and expect the sector to lean harder on brand names, house terminology, and technical process descriptors (CVD, HPHT) where the Blue Book does not reach.

Caught in the middle, and carrying the operational burden.

GIA moved first, in 2025, which now looks well-timed. Other labs face a straightforward choice: align with CIBJO or explain the divergence. Grading reports are the documents that follow a stone through resale, appraisal, and insurance for decades — so report language has unusually long half-life, and inconsistency across labs creates durable confusion in the secondary market.

The intended beneficiaries, and the group whose actual response is hardest to predict.

The best case is exactly what Abouchar describes: clearer language, better-informed purchase decisions, restored confidence in disclosure. The risk case is a transition period in which the same product is called different things in different places, and clarity gets worse before it gets better.

There is also a substantive secondary effect worth naming: to the degree "synthetic" depresses perceived value, it may pull consumer expectations about resale value closer to reality. Lab-grown diamond resale values have been weak and falling — a function of scalable production and continually declining wholesale prices. Language that discourages consumers from treating these stones as value-retaining assets is, arguably, protective, whatever the motive behind it.

Any honest analysis has to sit with the obvious question. Is this consumer protection or competitive positioning?

The case for consumer protection:

The case for competitive positioning:

The most defensible conclusion is that both things are true simultaneously. The definitional argument stands on its own merits. The word selected among defensible options happens to be the one most commercially favorable to the constituency making the decision. Standards bodies are composed of industry participants; that is how they get their expertise, and also how their interests enter their outputs.

The practical implication is that the natural sector should not expect this to settle the question, and the lab-grown sector should not expect the Blue Book to be reversed. Terminology disputes of this kind get resolved by regulators and courts, not by glossaries — and that process is only beginning.

CIBJO's decision is best understood not as a glossary revision but as the formal closing of an eighteen-month realignment. GIA moved, BIS moved, the ADPA moved, Russia moved — and the Blue Book now consolidates that drift into the trade's reference standard.

The definitional case is legitimate: reactors are not laboratories, and manufacture is not growth. The commercial case is equally legitimate to observe: among several accurate alternatives, the term selected is the one that most clearly separates manufactured stones from mined ones in the consumer mind, chosen by bodies with a direct interest in that separation.

Both readings can be held at once without contradiction.

What is not in doubt is the operational reality. From September 2026, anyone selling manufactured stones into markets that follow CIBJO guidance is working with a different vocabulary — and, in Russia, a different unit of measure. The businesses that treat this as a compliance project starting now will absorb it cleanly. Those that treat it as a distant standards-body footnote will be rewriting product catalogues under deadline pressure in the fourth quarter, during peak selling season.

The word has changed. The chemistry has not. The market will spend the next two years working out how much that distinction is worth.