Diamonds Are Forever, But De Beers Might Not Be

The Greatest Marketing Trick Ever Sold

In 1938, De Beers hired the ad agency N.W. Ayer, and by 1947 copywriter Frances Gerety scribbled 'A Diamond Is Forever' at 1 a.m. because she'd forgotten to finish the campaign. That four-word accident became one of the most effective slogans in history — it welded a shiny rock to the idea of eternal love and, crucially, told everyone you should never resell it. No resale market means no downward price pressure. Genius.

De Beers didn't just sell diamonds — it invented the demand and then controlled the supply. At its peak it moved roughly 80–90% of the world's rough diamonds, hoarding stock in London vaults to keep prices artificially high. They even seeded the 'two months' salary' rule out of thin air. It was never about geology. It was about narrative discipline.

For most of the 20th century it worked flawlessly. Scarcity plus sentiment equals margin. The problem with a story-based moat, though, is that stories don't stop bullets — or reactors.

China Built the Machines That Broke the Myth

Lab-grown diamonds aren't fakes. Via CVD (chemical vapor deposition) or HPHT (high pressure, high temperature), you grow real carbon-lattice diamonds — same hardness (10 on the Mohs scale), same refractive index, same fire. Even trained gemologists need specialized machines to tell them apart, because there's nothing to tell apart chemically.

Provinces like Henan turned this into heavy industry. Reports point to thousands of HPHT presses churning out gem-quality stones at plummeting cost — a rough carat that once implied thousands of dollars of 'rarity' can now be produced for a few hundred. When you can print scarcity, scarcity stops being a business model.

The result: analysts have tracked lab-grown wholesale prices falling on the order of 96% since 2018. A stone that wholesaled around $2,400/carat has been quoted near $80. Retail hasn't fully caught down yet — jewelers love margin — but the wholesale floor fell out of the elevator shaft.

A $6.8 Billion Bruise

De Beers' parent, Anglo American, took a reported $6.8 billion impairment on the diamond unit as the market soured. The company that spent 80 years insisting diamonds hold value had to formally write down the value of its own diamonds. There is no slogan for that.

Anglo American publicly signaled it wants out of diamonds entirely — exploring a sale or spin-off of De Beers, the cartel that once was the industry. When the house that built the myth quietly puts the myth on the market, you're watching an era end in real time.

The irony is thick as vault glass: the same scarcity engineering that made diamonds a store of value can't survive an actual abundance of the product. De Beers taught the world diamonds were rare and forever. The world took 'forever' literally and mass-produced them.

Should You Care as a (Non-)Shopper?

If you're buying an engagement ring, the practical takeaway is brutal but freeing: a lab-grown diamond is optically and chemically indistinguishable from mined, dramatically cheaper, and doesn't carry the ethical baggage of conflict sourcing. The only thing you're paying extra for with mined stones is a certificate that says 'came out of the ground.'

But here's the resale gut-punch that applies to both: diamonds have always been terrible investments. That old 'diamonds don't lose value' line was cartel maintenance, not finance. With lab-grown prices collapsing, both categories are depreciating assets you wear on your hand. Beautiful? Yes. Store of value? Never was.

So the smartest move might be the DopamineKart move: browse a two-carat flawless stunner, marvel at how the price fell off a cliff, and check out for $0. All the sparkle, none of the sunk cost.

What Happens to a Cartel With No Scarcity?

De Beers is pivoting to what marketers do when the product fails: sell the story harder. Expect a doubled-down push on 'natural' diamonds as heritage luxury — the way vinyl and film cameras got repositioned as authentic vs. digital. The pitch shifts from 'rare' to 'real,' where 'real' now means 'took a billion years' instead of 'took two weeks.'

Whether that works depends on whether Gen Z buyers care about geology as romance. Early signs suggest they'd rather pocket the savings, or spend the difference on the honeymoon. Sentiment is durable; overpaying for sentiment is not.

Meanwhile the wholesale reality keeps compounding: more reactors, more supply, more downward pressure. The cartel spent a century controlling the top of the funnel. It never controlled the physics.

De Beers taught the world diamonds were forever — the world took it literally and started printing them for $500.