Where do diamonds come from? A guide to origins and mines

Every diamond is a time traveller. Formed one to three billion years ago, some 150 kilometres beneath your feet, under pressures capable of crushing any other material, expelled to the surface within hours by a volcanic eruption of extraordinary violence, lying dormant in the earth for millions of additional years before being discovered, extracted, cut, and set into a piece of jewellery. This remarkable journey, from the Earth's mantle to your hand, deserves to be understood.

The origin of a diamond tells you a great deal about what it is. It also reveals much about the conditions in which it was mined, the people who worked to bring it to light, and the chain of responsibility that delivers it to you. Explore our diamond guide for a comprehensive overview of its properties and quality criteria.

Diamond is pure crystallised carbon formed under conditions that nothing on Earth can easily replicate: approximately 5 gigapascals of pressure and temperatures between 1,200 and 1,400 degrees Celsius. These conditions exist at depths of 150 to 200 kilometres, in a region of the Earth's mantle that geologists call the "craton": the ancient, extraordinarily stable cores of the continents. It is here that carbon reorganises itself, atom by atom, into a cubic crystal lattice, the structure that gives diamond its absolute hardness.

The age of a diamond is almost beyond human comprehension. A typical crystal is between 1 and 3 billion years old. To put that in perspective: the Earth is 4.5 billion years old, and multicellular life only appeared 600 million years ago. Some diamonds contain mineral inclusions dating back 3.5 billion years, fragments of minerals older than any living creature that has ever existed.

Diamonds do not reach the surface on their own. They are carried upward during extraordinarily deep volcanic eruptions known as kimberlitic eruptions, which create channels of volcanic rock called "kimberlite pipes." The ascent speed is estimated at between 50 and 100 kilometres per hour: were it any slower, the gradual drop in pressure would convert the diamond into graphite, its stable form at low pressure. Only a tiny fraction of these eruptions contained diamonds in quantities worth mining. It is this geological rarity that underpins the value of the stone.

Source: GIA, Diamond Formation

If you are wearing a diamond today, there is a strong chance it came from Botswana. The Jwaneng and Orapa mines, operated by Debswana, together account for approximately 25 to 30 percent of global diamond production by value. Jwaneng, discovered in 1973, is considered the richest mine in the world by value per tonne extracted. Orapa is the largest in the world by surface area.

What sets Botswana apart from other producing nations is its economic model. Debswana is a 50/50 joint venture between the Botswana government and De Beers, with the government holding a seat at the table over its own resources, unlike many other producing nations where mining assets are controlled by foreign interests.

The impact on the country is well documented and measurable. At the time of independence in 1966, Botswana was one of the poorest countries in the world. Today, it is a stable, middle-income African economy, with diamond revenues massively reinvested in education, healthcare, and infrastructure. Diamonds represent approximately 70 percent of exports and 40 percent of government revenue. It is the most frequently cited example in economic literature of successful natural resource governance.

The symbolic significance of the diamond is deeply tied to these African origins, which make it far more than a precious stone.

It all began with a 15-year-old boy. In 1867, Erasmus Jacobs discovered a diamond near the Orange River in South Africa, not knowing what it was. In 1871, the Kimberley mine was officially opened, and it is from this name that the term "kimberlite" derives, used today by geologists around the world to describe the volcanic pipes that contain diamonds.

The Kimberley mine yielded more than 14.5 million carats between 1871 and 1914. The Big Hole of Kimberley entered history as the largest hand-dug excavation in all of human history: 215 metres in diameter, 240 metres deep, dug largely by contract workers under conditions that now belong to the darker chapters of colonial history.

Today, the Venetia mine (operated by De Beers as an underground operation since 2021) remains one of the most significant in South Africa. The country is particularly renowned for producing diamonds of exceptional size: the Cullinan (3,106 carats, discovered in 1905) was found there, and remains to this day the largest rough diamond ever recovered.

Canada's mines, Ekati (opened in 1998) and Diavik (2003) in the Northwest Territories, arrived late in the global story of diamonds. Yet they transformed it entirely.

Subject to Canadian federal and territorial environmental standards, among the most stringent in the world, each mine must complete comprehensive impact assessments before opening and plan for site restoration from day one. Transparency reports are made public. This represents a fundamental difference from many mines elsewhere in the world.

Another distinguishing feature: mandatory consultations with Indigenous communities (Inuit, Dene) govern every mining project. These agreements guarantee local employment, training programmes and a share of economic benefits.

The result: Canadian diamonds are among the most traceable on the market. Their certificate of origin can be verified back to the specific mine. They command a price premium justified by this transparency. With the Ekati mine approaching the end of its productive life, Canadian output is declining, further enhancing its rarity and value.

ALROSA, a Russian state-owned company, is one of the world's largest producers, accounting for approximately 25% of total volume. The Mirny mine, opened in 1957 in eastern Siberia, is iconic: a crater measuring 525 metres in diameter and 340 metres in depth, closed in 2004 following a flood. Today, ALROSA operates primarily the Udachnaya and Aikhal mines in Siberia. In the current geopolitical context (since 2022), the trade in Russian diamonds has been subject to increasing restrictions from the European Union and the G7.

Other countries deserve mention, each with important nuances. Angola has significantly improved its diamond governance over the past twenty years. The Zimbabwe region, particularly Marange, continues to raise concerns documented by human rights organizations regarding mining conditions. Sierra Leone has rebuilt its diamond sector following the civil war years of the 1990s.

The Argyle mine in Western Australia, closed in 2020, deserves special mention: for decades, it was the largest diamond mine in the world by volume, and the only significant global source of natural pink and red diamonds. Its closure triggered a sharp rise in pink diamond prices, with existing stocks becoming irreplaceable.

Before Kimberley, before Argyle, before ALROSA, there was Golconda.

The mines of the Golconda region, in present-day Andhra Pradesh, India, represent the earliest known diamond mining operations in history. Indian records document extraction as far back as the 4th century BCE, and likely earlier still. Ancient Indians called the diamond "vajra" (lightning) and "heera" (precious stone), recognizing its spiritual and martial virtues long before the Greeks coined the name "adamas."

Some of history's most celebrated diamonds originated from Golconda, including the Koh-i-Noor (105.6 carats, now set within the British Crown Jewels), the Hope Diamond (45.52 carats, Smithsonian Institution, Washington), the Regent Diamond (140.64 carats, the Louvre), and the Grand Mogul and many others. These mines were gradually exhausted between the 17th and 18th centuries.

The discovery of diamonds in Brazil in 1725, in the province of Minas Gerais, marked a turning point: Brazil became the world's leading producer for nearly 150 years, until the South African discovery of 1867 quickly overshadowed it.

What these mine closures teach us: diamond deposits are non-renewable resources. Every mine that closes reduces the global supply and reinforces the rarity of natural stones, a reality that laboratory diamonds, reproducible in endless quantities, do not share.

Regardless of the mine a rough diamond comes from, whether Botswanan, Canadian, or Australian, it will almost certainly pass through Antwerp before being cut. Approximately 80% of the world's rough diamonds transit through this Belgian city to be evaluated, graded, sold, and redistributed. A concentration unparalleled in the history of precious commodities trading.

The Diamantkwartier, Antwerp's diamond district, is concentrated along a few streets in the city centre. It is home to approximately 1,500 specialist firms: rough diamond traders, brokers, cutters, insurers, and certification laboratories. Two major exchanges, the Antwerp Diamond Bourse and the Beurs voor Diamanthandel, ensure market liquidity. HRD Antwerp (Hoge Raad voor Diamant), the Belgian certification body equivalent to the American GIA, is also based there.

After trading in Antwerp, the vast majority of diamonds are sent to Surat, in India, where approximately 90% of the world's diamonds are cut. Mumbai, Israel, Belgium, and the United States host cutting facilities for high jewellery and exceptional stones.

In the 1990s, several African civil wars, in Sierra Leone, Angola, and Liberia, were partially funded through the sale of rough diamonds by armed rebel groups. These stones became known as "blood diamonds" or "conflict diamonds." The combined pressure of NGOs, governments, and the media led, in 2003, to the launch of the Kimberley Process Certification Scheme (KPCS).

The KPCS today brings together 85 member countries representing approximately 99% of global production. Its mechanism: every shipment of exported rough diamonds must be accompanied by an official certificate from the exporting government, guaranteeing that the stones do not originate from armed rebel groups acting against a legitimate government.

What the KP covers: uncut rough diamonds. Transit between member countries with documentation. The prohibition on importing diamonds from non-member or non-compliant countries.

What the KP does not cover: human rights abuses in legal mines (working conditions, safety, child labour in certain contexts). The distinction between democratic and authoritarian governments. Cut or set diamonds. Global Witness, one of the founding organisations of the KP, withdrew in 2011 to publicly denounce these shortcomings.

The Kimberley Process remains an essential regulatory baseline. But it does not, on its own, constitute a sufficient guarantee of responsible sourcing.

Between the mine and your jewel, a diamond passes through many hands and several continents. The main stages: extraction (mine), followed by sorting and assessment of the rough stone (grading by colour, quality, and potential size), then transit through Antwerp for classification and trading, then cutting (primarily Surat, or Israel and Belgium for exceptional stones), then a diamond wholesaler, then a jeweller, and finally the finished piece.

Cutting is a discipline in its own right. A cutter analyses each rough diamond under a loupe and through 3D modelling before making any decision. Losing 50% of the rough weight is entirely normal: a 2-carat rough stone will often yield a cut stone of 0.9 to 1.0 carat. The quality of the cut determines the fire and brilliance of the finished stone, which is why cut is the first of the 4Cs in terms of visual impact.

Traceability relies on several complementary mechanisms. The GIA (Gemological Institute of America) laser-engraves a unique number on the girdle of each certified diamond, invisible to the naked eye and readable under a microscope, linking the stone to its certificate. More advanced systems, including isotopic tracing and geochemical analysis, can in some cases determine the precise geographical origin of a stone from its chemical composition.

We source our diamonds exclusively from Kimberley Process-certified suppliers, based in Antwerp and Paris, with whom we have maintained direct, documented relationships for several years. This is not a commercial stance; it is a fundamental requirement we apply to every single lot.

For significant pieces, we require a GIA certificate or equivalent for diamonds above 0.5 carat, which precisely documents the quality of the stone (colour, clarity, cut, and weight). This certificate, together with the laser-engraved number, connects each diamond to its full traceability chain.

Our commitment goes beyond the regulatory minimum: we favour suppliers capable of document the precise geographical origin of their lots (Botswana, Canada, South Africa), not simply KP compliance. The Kimberley Process is a starting point, not a destination.