Diamonds

Diamonds as an Investment: An Honest Conversation

23 June 2026 · By Johan Poggenpoel · 1 min read

I've owned some special diamonds over the years. Unique colours, exceptional purities, stones that stopped you in your tracks. They've all had a price, and they've all found a home.

Something we've never done in almost three decades in this industry: sold a diamond as an investment. That's not a recent change of heart — it's a position I've held for a long time, and one I'm more convinced of now than ever.

What the numbers say

Let's start with context, because the numbers here are striking.

Measured in USD from 2020 to 2026:

Gold is up roughly 170%
Silver is up roughly 230%
Gem-quality mined diamonds are down over 40%

That's not a blip. That's a structural shift. And it deserves an honest explanation — not the kind of carefully worded non-answer you'll get from someone with a parcel of overpriced diamonds to move.

For South African buyers, the rand picture adds another layer. Gold in ZAR terms has performed even more dramatically than the USD numbers suggest, because the rand has weakened significantly over the same period. So while your gold holding was compounding in dollar terms, it was also getting a tailwind from currency. Diamonds gave you neither.

What caused the diamond price collapse?

Two things happened more or less simultaneously, and together they were devastating for diamond prices.

Supply manipulation unravelled.

For decades, a small number of dominant producers — De Beers chief among them — managed the rough diamond supply with extraordinary discipline. Throttling supply to sustain prices is, in hindsight, exactly what was happening.

That grip has loosened significantly over the last few years. The Anglo American attempted sale of De Beers, the subsequent chaos in the rough diamond market, De Beers cutting rough prices to try to clear inventory — all of this played out publicly and in real time. When the supply management fails, prices find their natural level. And natural level, it turns out, is considerably lower.

Lab-grown diamonds changed the demand picture permanently.

Nobody in the trade foresaw exactly how receptive buyers would be to lab-grown diamonds. Once people understood that a lab diamond is physically, chemically and optically identical to a mined diamond — same hardness, same brilliance, same everything — resistance dropped fast. Demand for mined diamonds fell as lab demand rose, and that shift has not reversed.

What happened to lab diamond prices in response to their own popularity? They collapsed too, for a different reason: there is no supply ceiling. As demand increases, producers simply build more CVD and HPHT reactors. The production cost has largely bottomed out — the floor is essentially the energy cost of running the equipment — and with many producers competing on price, lab diamond prices have fallen dramatically and will likely stay in this range. There's no cartel to prop them up. There's no scarcity story to tell.

The real-world Rand-value calculation

Here's the analysis I find most useful, and it rarely gets discussed properly.

Even though lab diamond prices have dropped more steeply in percentage terms than mined diamonds, your actual rand loss on a lab diamond is considerably smaller.

Consider this: a R50,000 mined diamond purchased a few years ago might be worth R30,000 today. You're R20,000 down. But if you'd bought a comparable lab-grown stone at the time — let's say R15,000 — you might be sitting at R6,000 today. You're R9,000 down.

The percentage loss on the lab stone is worse. The rand loss is almost a third of what you'd have experienced on the mined stone.

The seller’s blindside: liquidity

This is the single most important thing most diamond buyers don't understand until the moment they try to sell.

Diamonds have almost no secondary market liquidity.

You cannot sell a diamond on an exchange. There is no spot price. There is no transparent, publicly available market price you can verify on Bloomberg or Reuters the way you can with gold, silver, platinum, or virtually any other commodity. When you try to sell a diamond, you are not selling into a market — you are negotiating with individual buyers, each of whom has their own cost price and margin expectations, and none of whom are in a hurry.

The further you bought from the source, the worse this problem is. Diamonds pass through many hands — mine to polishing factory to dealer to broker to jeweller — and each party added their margin. When you sell, you are selling back into that chain from the wrong end. You will not recover those margins.

This isn't a knock on the industry. It's just the nature of a product that has no standardised exchange, no commodity benchmark, and no mechanism for price discovery beyond willing buyer and willing seller negotiations.

The valuation certificate problem

It's worth understanding what a diamond valuation certificate actually represents. Insurance replacement valuations — the most common type — reflect the retail replacement cost at that point in time, often at the higher end of the market. They are not a resale value. They are not a market value. They are what it would cost your insurer to replace the item at retail if it were lost or stolen.

When diamond prices fall, replacement values fall too. The certificate doesn't represent what you'd get if you sold the stone. It never did. And in a falling market, the gap between replacement value and resale value becomes particularly painful.

Where you buy matters more than ever

Because there is no transparent market price, the price you pay is entirely a function of whose counter you're standing at. And some counters are dramatically more expensive than others.

The most expensive place to buy a diamond, by a meaningful margin, is a traditional mall-based jeweller. The overheads of prime retail space, elaborate fitouts, large staff complements and heavy marketing budgets all have to be recovered somewhere — and they're recovered in the price of the product.

Buying closer to the source — from established jewellers without the premium retail overhead — gives you meaningfully better value. Very few top-tier diamond factories deal directly with the public unless you're buying in significant volume. But there's a middle tier of established direct jewellers, like us, where you're getting considerably better value than mall retail without compromising on quality, certification or craftsmanship.

If you're buying a diamond with any investment intent at all, buy certified. GIA and IGI are the internationally recognised grading laboratories. An uncertified stone — however good it looks — is essentially unsellable at any rational price to any buyer who takes it seriously.

Can mined diamond prices recover?

Possibly.

The conditions that would drive a meaningful recovery: a significant tightening of rough supply (possible if major mines deplete without replacement discoveries), a reversal of lab diamond adoption sentiment (unlikely in the near term), or a major macro shift in commodity buying patterns.

The conditions working against recovery: lab diamond availability as a viable, genuinely identical substitute, continued loosening of the traditional supply management structure, and the general uncertain macro environment.

I won't pretend I know where the bottom is, or whether we're past it. What I can say is that at current prices, mined diamonds are at their most accessible in a very long time. Whether that's the bottom or a waypoint is something nobody can say with certainty.

The reframe that actually matters

Here's the thing: you're probably more underwater on your last car than you are on any diamond you've bought. And you don't lose sleep over it, because you understand what you were paying for when you bought it. The car gave you utility, freedom, convenience. You weren't expecting it to appreciate.

The dream holiday you took. The dinners. The experiences. You spent real money on those and the financial return was zero, and you'd do it all again.

An engagement ring is the most significant gift you'll ever place on someone's finger. It marks a moment that doesn't have a price. It carries sentiment across generations in a way that a share certificate simply doesn't. It will sit in a family for decades, maybe longer, accumulating meaning that no commodity price index can capture.

Modern diamond jewellery isn't an asset class. And the sooner we all — buyers and sellers alike — stop pretending otherwise, the more honestly and usefully we can have this conversation.

My view in 2026

Diamond prices today — both mined and lab — are genuinely excellent. Some of the best buying conditions we've seen in years.

If you're in the market for a diamond, whether for an engagement ring, a significant piece of jewellery, or simply because you love what diamonds are and what they represent, now is an exceptional time to buy well. The priority should be buying the best stone you can at the best possible price from a source you trust — not trying to time a commodity cycle that doesn't behave like any other commodity on earth.

We'll gladly join you on that journey.

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