Finn Brooks: Can I just — I know we were gonna ease in but I've been genuinely bothered by something since Tuesday and I need to just say it.
Clara Bennett: Long week already — go ahead.
Finn Brooks: There's a factory in Zhengzhou, China — a company called Jiaruifu — growing a one-carat diamond in two weeks for ten percent of what it costs to mine one. Ten percent. And that one fact is apparently enough to crater De Beers so badly they're cutting over a thousand jobs and drop Alrosa's profits by nearly eighty percent and force Debswana to slash production by twenty-seven percent in a single year.
Clara Bennett: Ten percent of the cost is — yeah, that's not a price war. That's a different product category masquerading as the same one.
Finn Brooks: And consumers are buying it. Forty-five percent of engagement rings in the U.S. are lab-grown now. That is not fringe.
Clara Bennett: Now, the paradox worth sitting with — Grand View Research values the overall diamond market at forty-two-point-seven billion dollars in 2025, projected to grow. So the market is bigger. The miners are dying. Those two things are both true at once.
Finn Brooks: Which is — okay, that's genuinely disorienting. And the places absorbing the damage aren't abstract: Botswana's national economy is directly tied to Debswana, and India's entire diamond cutting and polishing sector is losing work because fewer natural rough diamonds need to be processed.
Clara Bennett: So the real question is whether this is disruption — which implies survivors — or replacement, which doesn't.
Finn Brooks: Okay but — replacement is what I'm leaning toward, and here's why. Because this isn't just about price. The actual new thing, the thing people keep skating over, is that HPHT and CVD produce stones that are chemically and physically identical to mined diamonds. Not similar. Identical. A geologist cannot tell them apart without specialist equipment.
Clara Bennett: That's the click, right there. Think about it this way — imagine a factory that makes water chemically identical to ancient glacier melt, in two weeks, for a fraction of the price. You cannot argue the glacier water is better on any molecular level. The only argument left is the story.
Finn Brooks: And Jiaruifu — Feng Canjun's operation in Zhengzhou — basically proved that story doesn't hold at commercial scale.
Clara Bennett: Now, the market numbers make that concrete. The LGD market was valued at around twenty-nine-point-seven billion dollars in 2025 — and it's projected to hit nearly ninety-eight billion by 2034. That's a fourteen-point-one-five percent annual growth rate. That is not hype, that's capital following a structural shift.
Finn Brooks: Wait — ninety-eight billion? By 2034?
Clara Bennett: Ninety-seven-point-eight-five, yeah. And the reason that number matters is — actually, no, let me put the sequence right — because China didn't just enter this market. China industrialized it. Once Zhengzhou producers flooded global supply, commercial-grade natural diamond prices collapsed. That is what stripped De Beers of its pricing power. Not a new competitor. The elimination of scarcity as a fact.
Finn Brooks: So De Beers spent a century building the scarcity argument and one category of factory just... made it untrue.
Clara Bennett: In practice, yes. And 2025 academic research actually documented this formally — LGDs fragmenting what was a historically oligopolistic structure that De Beers anchored for decades. That's not commentary, that's peer-reviewed confirmation that the structural change is real and measurable.
Finn Brooks: So the headline says 'lab diamonds are rising' and the actual story is 'oligopoly pricing just lost its foundation and nobody can rebuild it because the scarcity is gone at the product level.' Those are very different sentences.
Clara Bennett: And yet the take I keep seeing—the one doing rounds—is that Gen Z is buying lab-grown because they're cheap and don't know any better. That framing is wrong, and I think it's importantly wrong.
Finn Brooks: Okay, that one actually drives me a little crazy. Because there's 2025 research—Gen Z consumers in India, which is not a market where you just casually abandon diamond tradition—citing specifically 70% lower carbon emissions and 30 to 50% lower prices. They're not confused. They're making a values argument.
Clara Bennett: And Signet Jewelers adding LGDs to their retail portfolio — that's not a retailer leading taste. That's a retailer chasing where the consumer already went.
Finn Brooks: Right — but here's where I want to stress-test the values piece, because the sustainability claim is... I mean, does it actually hold?
Clara Bennett: No, and that's the real complication. If the diamond is grown in a coal-powered factory in China — which a significant share of them are — the 70% lower carbon number becomes, at minimum, contested. The industry is borrowing an environmental halo it hasn't fully earned yet.
Finn Brooks: Wait, so the values-driven Gen Z buyer who thinks they're making the ethical choice might actually be — I mean, not necessarily making the ethical choice?
Clara Bennett: Potentially. The carbon profile depends entirely on where and how the stone was grown. That's a fact the marketing hasn't caught up to.
Finn Brooks: Okay but — okay I love that complication, BUT — even if the carbon math is messier than advertised, the demand shift feels durable to me. Because the price signal is real, the blood diamond narrative is real, and Gen Z has already emotionally closed the door on mined. You can't un-ring that bell even if the emissions data gets revised.
Clara Bennett: Durable shift, contested premise — I'll grant that. And the part that comes later is where this gets genuinely uncomfortable: premium natural diamonds may hold, but the commercial-grade volume that actually funds mining operations is gone, and some African operators could hit break-even thresholds as early as 2027.
Finn Brooks: 2027 is — wait, that's three years from now. That's not a long-runway warning, that's basically already happening.
Clara Bennett: Picture a retailer — let's say a Signet Jewelers floor in 2027. A couple walks in. She picks up a lab-grown stone, no hesitation. He looks at the natural tag next to it, which is five times the price, and genuinely cannot explain what he's paying for. The retailer has both. That is the bifurcated market in one moment.
Finn Brooks: And the retailer is fine. Signet already moved. It's Debswana that's — I mean, Botswana doesn't have a Signet pivot available to it.
Clara Bennett: That's the mechanism worth watching. De Beers can defend ultra-premium — the investment-grade stones, the heritage narrative, the collector tier. That segment holds, maybe. But the commercial-grade volume? That's what actually funds the infrastructure. The roads, the equipment, the Debswana payroll. And there's no premium story to tell about a commercial stone when an identical one costs ten percent as much.
Finn Brooks: So De Beers keeps the trophy case and loses the engine room.
Clara Bennett: Exactly — and the 2027 to 2028 window is when analysts expect African mining operators to actually hit break-even thresholds. Not projecting stress. Closure thresholds. Debswana already cut twenty-seven percent in 2024 with more reductions projected for 2025. That trajectory doesn't bend upward without a demand reversal that isn't coming.
Finn Brooks: Okay but — no, hang on — the part that I can't stop thinking about is what happens one generation further. Because right now the premium tier survives on cultural transmission, right? Parents who grew up with 'a diamond is forever' passing that down. But if Millennials and Gen Z never absorb that story — and the research is pretty clear they haven't — then who inherits the premium tier's floor?
Clara Bennett: That's the slow liquidation scenario. The bifurcation holds as long as the cultural attachment to natural origin gets transmitted. The moment that inheritance breaks — actually, it's not even a crash, it's more like a floor that quietly dissolves. The premium tier doesn't collapse, it just... loses its reason to exist at scale.
Finn Brooks: And then the bifurcation wasn't a stable ending. It was just — it was the last chapter before the category folds from the bottom up.
Clara Bennett: And nobody gets to stop that clock. That's what sits with me. De Beers can't buy back the cultural moment. Botswana can't manufacture a new industry by 2027. The question isn't whether the premium story survives — it's who actually has the credibility to tell it. Is it De Beers? A jeweler with an origin certificate? Botswana itself?
Finn Brooks: And when forty-five percent of engagement rings are already lab-grown — I mean, that number didn't sneak up on anyone, it just... nobody with power in the natural diamond supply chain had a real answer to it. And I don't think they have one now. That's the part I'm left holding.
Clara Bennett: Mm. We'll know within a generation whether the premium survives or whether this is just a slow liquidation dressed up as a two-tier market. I genuinely don't know which.
Finn Brooks: Yeah. Neither do I.
Clara Bennett: Good conversation. Thanks for bringing the Zhengzhou thing on a Tuesday.
