The following article is the text that I use for the Great Business Stories podcast on this topic. To listen to the podcast, click on this link or alternatively listen to Great Business Stories on Spotify or Apple Podcasts.

This is fascinating episode where we do a brief history of diamonds- what are the biggest, most valuable diamonds, and then we dig into some of the key people -how Cecil Rhodes built De Beers into a diamond monopoly, how Ernest Oppenheimer transformed diamonds by more or less inventing the concept of the diamond engagement ring, how Beny Steinmetz  who built a $6 billion fortune has seen that dwindle and faces extradition and jail terms in different jurisdictions, and how the emergence of lab grown diamonds has exploded in the last decade- it’s a fantastic episode with so many different stories- enjoy.

The First Spark: India and the Diamond’s Origin Story (4th Century BCE – 18th Century)

So the word “diamond” comes from the Greek adámas. It means “unbreakable.” Or “invincible.” Which—of clourse—makes total sense. Hardest natural substance on Earth. But where did it all begin?

India. Specifically, the Golconda region. We’re talking 4th century BCE, and back then, diamonds weren’t just decoration. They were spiritual—woven into Hindu and Buddhist traditions. They stood for strength. Protection. They were sacred. But of course they were also beautiful. And rare. Which meant rulers wanted them and traders chased them.

And then came the legends.

The Koh-i-Noor. Massive. 105 carats. That’s 21 grams in weight, 3.6 cm long, 3.2 wide, 1.3 deep. It’s been through wars, empires, dynasties. Eventually, it lands on Queen Elizabeth’s crown in 1937. Today, you’ll find it in the Jewel House at the Tower of London. Value? Nobody knows for sure. Some say $140 million. Others say $400 million. But most agree—it’s priceless.

Then there’s the Hope Diamond. Smaller, yeah. But still a heavyweight at 45.5 carats—about 9 grams. This one? Pure drama. It starts with French royalty. Gets stolen during the French Revolution. Disappears. Re-emerges in 1839 under the name “Hope,” tied to an American banking family. Then, years later, the American jeweler Harry Winston donates it to the Smithsonian in 1958. That’s where it lives now, under museum lights. Estimated value: somewhere between $200 million and $350 million.

Initially diamonds travelled from India into Persia, into Rome, into China by the silk road. By the time Europe started waking up to diamonds, Venice had already turned itself into a cutting hub. They refined the techniques. Boosted the brilliance. And by the 15th century, diamonds had become a symbol of European royalty.

For centuries, India was the only major player. That is, until the 18th century—when the mines started to go dry. 

Brazil’s Moment in the Spotlight (1725–1866)

India fades, and Brazil steps in. 1725 when diamonds are first discovered there. And for the next 150 years? Brazil becomes the world’s number one supplier.

The Portuguese, who had colonized Brazil from about 1500 knew what they had. And they weren’t about to let it slip away. They imposed tight colonial controls. Forced labor. Enslaved people working the mines to keep the stones flowing.

And from here we get this monster diamond=- with a question mark: the Braganza Diamond, also called the Great Diamond of Portugal. This thing was 1,680 carats. Let that sink in—sixteen times the size of the Koh-i-Noor. But is it even real? We’ll never know because it vanished in 1809. Many experts believe it wasn’t even a diamond at all. Might’ve been topaz. No one knows. No one ever will.

But by 1866, Brazil’s time was winding down. The mines were exhausted. The rush was over. And the diamond business moves to South Africa.

The Eureka Moment: South Africa and the Diamond Rush (1866–1914)

It kicks off when a kid finds a 21.25 carats stone beside the Orange River in 1866. They name it the Eureka. It was later cut into a 10.73-carat cushion-shaped diamond which is now on display at the Mine Museum in Kimberley, South Africa. 

That was the spark. That sets off the Kimberley Diamond Rush. Thousands pour in. By 1871, they’re digging into what would become called the Big Hole- this huge open pit considered the deepest hole excavated by hand. 

Enter Rhodes and the Empire of De Beers (1888–1947)

And this brings us to our first central character- Cecil Rhodes

Born in England, the son of a reverend, he moved to South Africa for health reasons but he also had family over there. He’s ambitious, and opportunistic- he arrives in  Kimberly just after the Eureka diamond find, and with backing from Rothchilds, he moves fast—buying up all of the smaller mines in Kimberley, merging rival claims.

In 1888, he created De Beers Consolidated Mines Ltd.

The name “De Beers”? It came from two Dutch brothers who owned a diamond mine.

By 1902, De Beers is the dominant diamond producer controlling 90% of global diamond production. 

But of course behind the glitter, the brilliance of the diamonds, there’s a pretty brutal, exploitative history and it continues to this day. 

Migrant workers—thousands of them—were packed into the mines. Twelve-hour shifts. Dangerous conditions. Early records show that in those first few decades, thousands died each year. And Cecil Rhodes enforced racial segregation with military precision. Black miners made one-tenth what white miners earned. They lived in locked compounds. No families. No freedom.

This is a guy who actively blocked land ownership for Black Africans. Pushed through a labor tax to force them into the mines. Raised the voting property threshold so high that most Black people couldn’t vote at all. And his justification?

“The native is to be treated as a child and denied the franchise.”

Rhodes didn’t invent apartheid—but he built the blueprint. The rules, the systems, the economic logic—they all trace back to him. But of course Rhodes and South Africa weren’t outliers - this was simply colonialism 101. Exploitation, dispossession, racial hierarchy. White settlers did the exact same in North America. In South America. In Australia. Different continents, same playbook.

Ernest Oppenheimer: Architect of a Modern Empire

Now let’s fast forward a bit to Ernest Oppenheimer. No relation to Robert Oppenheimer, the nuclear bomb guy. Ernest was born in 1880, in Germany. 

His diamond story kicks off in 1917, when he co-founds the Anglo American Corporation—AAC. He partners with an American engineer named William Honnold. And with a $5 million war chest from J.P. Morgan, they dive headfirst into the gold mines of East Rand, South Africa.

After World War I, diamond prices collapse. Panic across the industry. But Oppenheimer sees the opportunity. He starts quietly buying De Beers shares. Piece by piece. Until finally, in 1929, he becomes chairman.

And once he’s in charge, he starts stockpiling diamonds. To prop up prices. Keep demand steady. And even during the Great Depression he holds the line. Mines were shut or scaled back. De Beers didn’t do any discounting, they stockpiled diamonds rather than sell at lower prices, maintaining the illusion of scarcity. He famously said, “Our only real asset is the confidence of the public in the value of our product.”

And it worked. DeBeers emerged from the depression more powerful than ever.

But there’s one thing Oppenheimer is best remembered for—something that changed the entire world’s relationship with diamonds.

The Birth of a Symbol: The Diamond Engagement Ring

It’s 1947. De Beers team up with N.W. Ayer, a heavyweight ad agency in the U.S..

And they’re plan wasn’t to advertise De Beers. They were going to advertise an idea.

Frances Gerety, a copywriter at the agency, coins the phrase: “A Diamond is Forever.”

Four words. That’s it. In 1999, Advertising Age named it the best slogan of the 20th century. The campaign wasn’t about selling to the rich. It was about reaching everyone—and one of the original 1947 ads read: “A diamond is forever—the perfect symbol of your marriage vows.”

So this is the first time that they are linking diamonds to marriage, to permanence, to love.

Once people bought into that idea, and they were looking to buy a diamond, well with 90% of the diamond market, de Beers got 90% of the business.

They didn’t have to sell De Beers, or differentiate De Beers from the competition- there was no competition. For decades, the De Beers name didn’t even appear in the ads. It didn’t have to. That’s the beauty of having a monopoly- you can focus on selling an idea - and De Beers did this brilliantly.

How Diamonds Took Over Culture: De Beers Goes Full Tilt

Because not only did they create this link between marriage and diamonds, and that a diamond is forever, over the years they rolled out one of the most comprehensive marketing campaigns that embedded diamonds into popular culture.

Hollywood Gets the Script

First up, Hollywood. Throughout the 40’s and 50’s they rolled out something called the “Hollywood Personalities” program. They fed stories to newspapers—gossip columns, press kits—about movie stars proposing with diamonds. Then they paid film studios to bake diamond engagement scenes right into the scripts. Seamless product placement, decades before it was a thing.

And in Hollywood movies from back then, we can see diamonds becoming elevated as the ultimate symbol of love and glamour, most notably when Marilyn Monroes sings “Diamonds Are a Girl’s Best Friend” in 1953. And then of course Grace Kelly famously wore her actual engagement ring given to her by Prince Rainier of Monaco, 10.4 carats, worth about $40 million in the movie High Society.  

The Science of Romance

Then in the 1950s, De Beers rolls out the “4 Cs”—cut, carat, color, clarity. A global framework to assess diamond quality. But more than that, it added a scientific slant to the whole thing. Now, buying a diamond wasn’t impulsive—it was educated. It wasn’t always and necessarily emotional—it was could also be seen as a sound investment.

Setting the Price: The Two-Month Rule

Then came one of their most brazen and also brilliant moves.

In 1997, De Beers launch a TV ad where the narrator asks: “How else could two months’ salary last forever?” I mean, they’re not just romanticising the diamond—they’re telling you exactly how much to spend on it without actually putting a price on it- I think that’s brilliant. In Japan? They went even harder. Three months’ salary. 

The results of these advertising and marketing campaigns down through the decades speak for themselves.

In 1940, only 10% of American brides got diamond rings.

And today it’s over 90%

In Japan, less than 5% of brides wore diamonds in 1967. Today, it’s 80%.

And in China? In the 1990s, diamond engagement rings were unheard of. Today, it’s 47%.

And this can all be traced back to Ernest Oppenheimer. He died in 1957 and he left behind a complicated legacy. On one hand, he modernized South Africa’s mining economy. He invested in infrastructure, in schools, in hospitals. But on the other hand? He helped cement apartheid’s economic backbone. He’s a very interesting character and I think we’ll have to do a separate episode on him some day.

Beny Steinmetz: The Billionaire Who Played Dirty

Now from the culture behind diamonds popularity to corruption that a lot of people associate with the diamond sector and bodies embodies the dark underbelly of this better than Beny Steinmetz.

Born in 1956 in Israel, into the diamond business. His father Rubin was already a major player in the Israeli gem trade, and Beny picked up the torch early. By 21, he’d moved to Antwerp—the heart of the global diamond world—ready to expand internationally.

High Risk, Higher Returns

In 1988, he made his first big move on his own. Bought a diamond factory in South Africa and then expanded into other African countries such as Batswana and Angola. His strategy was simple: go where the rules are weakest and the resources are richest. Conflict zones, unstable governments—these were his playground.

As he told the Financial Times in 2012: “We invest in difficult places… You have to get your hands dirty.”

And man, did Beny get his hands dirty.

Through his company BSG Resources—founded in the ’90s—he expanded fast. Mining. Real estate. Energy. Spread across more than 25 countries. He worked with De Beers. He dealt with Tiffany. He built a property empire across Europe and the U.S.

At one point, his net worth topped $6 billion.

But when you’re doing business in massively corrupt countries, with very corrupt politicians, it’s pretty obvious that any business that thrives in these places will most likely be corrupt as well. Take for example Beny’s involvement in Simandou, Guinea in 2008- what has become known as the Simandou Heist.

So Simandou has one of the richest untapped iron ore deposits on the planet. In 2008, Steinmetz secured the rights to mine it. The cost? Practically nothing. Because he got them through bribes. Specifically, $8.5 million to Mamadie Touré—the wife of Guinea’s then-dictator, Lansana Conté.

Two years later, after investing $160 million, Beny’s company BSGR sold 51% of the mine for $2.5 billion. The Financial Times called it “the deal of the century.” Swiss prosecutors called it “corruption on an industrial scale.”

The Fallout Begins

Mamadie Touré fled to the U.S., where she signed an affidavit admitting the bribes—but refused to testify in court.

Meanwhile, Steinmetz’s associate, Frédéric Cilins, who subsequently pleaded guilty to corruption charges, was caught on FBI wiretaps repeatedly offering her millions of dollars to destroy her contracts with BSGR to ensure they didn’t fall into the hands of US investigators, while also telling Touré that he was acting on direct orders from Beny Steinmetz himself- this is all caught on tape. In 2021, Swiss courts convicted Steinmetz—five-year sentence (later reduced to three, with 18 months suspended). But the sentence was frozen pending appeals to Switzerland’s top court.

Next Stop: Romania

And it didn’t stop there.

Steinmetz got wrapped up in another scam—this one a land restitution fraud in Romania. The scheme aimed to illegally reclaim $100 million worth of state land once owned by the monarchy.

In 2020, he was convicted in absentia for this—another five-year sentence.

By January 2025, after being arrested in Athens, Greek courts ruled he’d be extradited to Romania. He was then released and fled to Israel where he currently lives.

And those convictions? They’re just the start. Beny’s been accused of everything from exploitative labor, farmland destruction, using armed security to crush protests.

Years of lawsuits, convictions, and asset freezes took their toll on poor Beny. BSGR declared bankruptcy in 2019. And as of today- it’s hard to know how much Steinbmetz has. Forbes last listed him in 2019 with a $1 billion valuation. Since then, it's likely fallen even further. Let’s hope so, because Beny is not my kind of guy. He and his wife and his supporters harp on about all of their charities and all the good work they do donating to schools, hospitals, army units and the arts in Israel. But Steinmetz made his money by preying on weak corrupt countries, and doing his very best to basically steal the natural resources that should be used to help the people of those countries- money that should be going to build the same type of schools and hospitals that Steinmetz now boasts about with his charitable donations. And Steinmezt could well say that he’s not responsible for running those countries, but he is responsible for facilitating the corruption.

But even worse than that, Steinmetz, together with almost everybody who dealt in African diamonds in the 90’s, they have blood on their hands because we can’t talk about diamonds without talking about blood diamonds also known as conflict diamonds.

In the 1990s rebel groups like UNITA in Angola and the RUF in Sierra Leone were selling diamonds to fund brutal civil wars. Not small numbers either—we’re talking billions of dollars flowing through these black-market networks.

And the estimate is that up 3.7 million people were killed during these conflicts. Men, women and children were enslaved and forced to dig for diamonds, while hundreds of thousands of children were forced to join the rebel armies. The atrocities are too numerous and gruesome to get into. And the big diamond companies including DeBeers, they weren't clean. Leaked documents exposed that even up to 1998, some of their subsidiaries were still buying blood diamonds. 

The Kimberley Process: A Patch, Not a Cure

Finally, in 2003, under pressure, the diamond industry took action.

They launched the Kimberley Process—a UN-backed certification scheme that required government-issued warranties for every shipment of rough diamonds. The idea was simple: if a diamond came from a war zone, it couldn’t be sold.

For the most part, it works. Conflict diamonds dropped from 15% of the global supply in the ’90s to less than 1% by 2003.

But it isn’t airtight.

There are loopholes. Weak enforcement in countries like Zimbabwe and Côte d’Ivoire lets smuggled diamonds slip through. And the system didn’t touch labor conditions or human rights abuses. It’s focused on war, not ethics. 

The Lab-Grown Boom: Ethics Meets Economics

And while it goes without saying that blood diamonds have left a terrible stain on the sector- when you have characters going back as far as Cecile Rhodes and right up the modern times with Beny Steinmezt, we can see that the diamond industry has always been a pretty nasty business. So it’s a kind of a big relief that over the last few years we’ve seen the emergence of the great disruptor in the sector,lab-grown diamonds.

They’ve actually been around since 1954. But for decades, no one paid attention. That changed in the 2010s. By 2023, lab-grown diamonds had exploded—grabbing 20% of the total diamond market. Virtually nothing in 2015, to billions in under a decade.

Why the sudden rise? 3 reasons.

One: they’re ethical and sustainable. No mining, no wars, no blood.

Two: quality and customisation- it’s also important to point out that lab diamonds are 100% real diamonds, with the same properties that natural diamonds have. 

Technological advancements have made it possible for these synthetic gems to match or surpass the quality of natural diamonds in clarity, color, and carat size. Couples can customize the diamond to reflect personal style. 

And three: they’re cheap. Really cheap. At first, lab-grown diamonds sold at a 10% discount compared to natural stones. Now? They're 60%-85% cheaper.

The market for lab-grown diamonds hit $22.66 billion in 2023. By 2032? Forecasts say $57 billion. Younger buyers are driving it—looking for conflict-free, eco-friendly jewelry that doesn’t break the bank.

My only worry about the growth of lab grown diamonds is that they have almost become too cheap, and this perception of cheapness, in a world where people are more than ever craving exclusivity, plays into the strength of mined diamonds..

The Industry Strikes Back

And that seems to be exactly what’s happening.

The traditional diamond industry has slashed production, scaled back operations, and doubled down on messaging. The story now? Natural diamonds are rare. They’re historical. They’re timeless.

But even within the traditional diamond market, the competition is fierce.

E-commerce has blown up. Blue Nile, not the river or the best band ever, but the online jewelry business, launched in 1999, helped digital retail hit 20% of diamond sales. Platforms like Brilliant Earth are pushing what they call “Beyond Conflict Free™” diamonds, sourcing from places like Canada.

The Big Players Move In

Luxury giants are reshaping the map and consolidation is happening.

In 2021, LVMH bought Tiffany for $15.8 billion—a massive move. In 2022, Signet Jewelers—the parent of Kay, Zales, Jared—swoops in and acquires Blue Nile, beefing up its market share.

Meanwhile, vintage diamonds have exploded. Between 2020 and 2025, vintage diamond sales grew 30% per year. Young buyers want sustainability. They want uniqueness. They want history without the guilt.

And now, blockchain is changing the game.

Platforms like Tracr and Aura are authenticating diamonds—tracking origin, handling, and sales. By 2024, 20% of the world’s diamonds were blockchain-certified. Full transparency. No guesswork.

The Collapse of a Titan

De Beers, the original titan of the industry, hasn’t adapted fast enough. In 2012, Ernest Oppenheimer’s grandson Nicky sold De Beers to the mining giant Anglo American for $5.1 billion.

Over the last few years Anglo has had to write down billions in value. They’re now actively looking to sell it. 

By the Numbers: The Market Shift

Consumer habits are rewriting the rulebook.

The diamond industry’s total revenue dropped from $81 billion in 2014 to $72 billion in 2023. That’s not a blip—that’s a trend. Lab-grown alternatives. Pandemic shutdowns. Generational change.

Natural diamonds aren’t dead. But they’re no longer untouchable.

Today’s consumer wants the sparkle—but they also want the story behind it. Where it came from. Who mined it. What it stands for.

And if they don’t like the answer?

They’ve got plenty of other places to look. And that’s how it should be. The history of diamonds is brutal, bloody and full of unscrupulous men who are willing to either participate or at the very least indirectly fund some of the worst atrocities just so they can get their hands on diamonds- it’s an industry that really shines a light on man’s greed- and I think that’s why it makes for such a great business story. I hope you’ve enjoyed it as much as I have, and remember if you have any comments, any corrections or any story that you’d like us to cover, email us at: info@gbspod.com

All the best folks