Where Do Diamonds Come From? The History of Diamonds, From Ancient Gems to Modern Jewellery

Every diamond on display in our showrooms started its journey roughly 150 to 200 kilometres beneath the Earth’s crust, billions of years before any human ever laid eyes on it.

That’s the literal answer to where diamonds come from, and it’s a far bigger story than most people expect when they’re standing at a counter comparing cut and clarity. Long before a stone reaches a ring setting, it’s already survived a journey most of us never think to ask about.

At Holloway Diamonds, we’ve spent 50 years mastering the science of sparkle, and Garry Holloway’s obsession with diamonds has always started with where they truly come from, not just how they’re marketed. What follows is part geology, part global trade story, part Australian mining history — and entirely relevant to how we source every natural stone we sell today.

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Where do diamonds come from? The science of formation

Before diamonds have any history at all, they have geology — and it’s remarkable.

According to research published by the Gemological Institute of America, natural diamonds typically form between 150 and 200 kilometres below the Earth’s surface, in the mantle, where temperatures reach over 1,000 degrees Celsius and pressure crushes carbon atoms into a tightly bonded crystal lattice. Many of the diamonds we handle every day are well over a billion years old; some are closer to three and a half billion.

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Diamonds don’t travel to the surface on their own. They’re carried up as accidental passengers in rare, violent volcanic eruptions that form vertical rock structures known as kimberlite pipes, and occasionally a rarer rock called lamproite. These eruptions are few and far between, which is precisely why gem-quality natural diamonds remain rare, no matter how many are mined each year.

The history of diamonds: from ancient India to global trade

Long before geologists understood how diamonds formed, traders and royalty understood exactly how rare and desirable they were.

For more than two thousand years, India was the world’s only known source. Alluvial stones washed from riverbeds around the Golconda region, in what’s now Telangana, supplied royal courts across Asia and, eventually, Europe. Many of history’s most famous diamonds, including the Koh-i-Noor, trace their origin back to these deposits.

India’s monopoly held until 1725, when Portuguese prospectors discovered diamonds in Minas Gerais, Brazil, while searching for gold. The real turning point came in 1866, when a young man named Erasmus Jacobs found the Eureka Diamond on the banks of South Africa’s Orange River. The rush that followed uncovered vastly larger deposits than anything Brazil or India had produced, and by the 1890s South Africa was supplying the overwhelming majority of the world’s diamonds.

That boom gave rise to the modern diamond trade. Cecil Rhodes founded De Beers Consolidated Mines in 1888, shaping how diamonds were marketed and priced for the following century. In 1931 the Gemological Institute of America was founded, later developing the 4Cs — cut, colour, clarity and carat — still used by every reputable jeweller today. And in 2003 the Kimberley Process Certification Scheme was introduced to curb the trade in conflict diamonds.

The evolution of diamond assessment didn’t end with the 4Cs. As research into light performance advanced, specialists began to question whether broad cut grades alone could predict how a diamond actually performs. Holloway founder Garry Holloway became part of that movement, developing the Ideal-Scope and later the Holloway Cut Adviser to assess cut and light performance beyond what a grading report provides.

How diamonds reached Australia: the Argyle story

For most of this history, Australia didn’t feature at all. That changed in 1979, when geologist Maureen Muggeridge discovered diamond samples in a Kimberley region creek bed feeding into Lake Argyle, in Western Australia’s remote north. Commercial production began in 1983, and the Argyle mine went on to become, at its peak, the world’s largest diamond producer by volume.

Argyle was geologically unusual: rather than the kimberlite pipes typical of South African and Canadian mines, its diamonds were hosted in lamproite. It became famous above all for colour, producing more than 90% of the world’s natural pink and red diamonds during its operating life.

According to Rio Tinto, which owned and operated the mine, Argyle produced more than 865 million carats of rough diamonds across 37 years before mining ceased in November 2020. Today, Argyle pink diamonds mined before closure remain highly sought after.

For Australian jewellers and clients alike, Argyle’s legacy is part of why natural diamonds carry a sense of place and history that a lab-grown stone, however well made, simply can’t replicate.

Natural diamonds vs lab-grown: a different origin story

Modern buyers now have two very different answers on where diamonds come from, and it’s worth understanding both before you choose.

This is precisely why Holloway Diamonds has only ever sold natural diamonds and gemstones, right from Garry Holloway’s very first showroom. When you trace the full story, from ancient Golconda riverbeds to the Argyle pink diamonds mined in our own backyard, it’s easier to see why a natural stone carries a different kind of significance than one grown in a lab last month.

Why this history still matters for ethical sourcing today

The history of diamonds is the reason ethical sourcing became such a serious issue in the trade, and why it still matters when you’re choosing a stone today.

Through much of the 20th century, diamonds from certain African conflict zones were used to fund armed conflict — a problem that became widely known as “blood diamonds”. In response, the international community introduced the Kimberley Process Certification Scheme in 2003, requiring participating countries to certify that rough diamonds are conflict-free before they enter the legitimate trade.

For Australian buyers, this is part of why sourcing transparency matters as much as the 4Cs. A stone’s origin — whether an Argyle-era Australian deposit, a modern Canadian mine or elsewhere — is something a reputable jeweller should be able to speak to clearly.

How this history shapes the way we source diamonds today

Every stone we sell is chosen with this history in mind. For round brilliant diamonds, we go beyond the GIA grading report using Garry Holloway’s Holloway Cut Adviser and Ideal-Scope to assess cut quality and light performance. It’s part of our broader approach to selecting natural diamonds for their rarity, beauty and performance — and a big part of why we believe everyone deserves a bit of sparkle, sourced with real transparency about where that sparkle came from.

Explore our range of diamond hoop earrings, or discover the full Holloway Diamonds jewellery collection at our Melbourne showrooms.

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