Where Do Diamonds Come From? Comparing the Origins of Natural and Lab-Grown Diamonds
A diamond in a jewellery display may once have rested beneath an ancient continent, or it may have crystallised inside growth equipment in a factory. Both are made of carbon atoms, but their journeys are very different: one depends on geological processes bringing a crystal within reach of mining; the other depends on engineers creating the conditions for crystal growth.
To understand the difference between natural and lab-grown diamonds, start with a more basic question: where does their carbon come from, and how does it become diamond? Following that question connects mines, seeds, machines, costs and environmental effects into a clear story of origin.
Illustration of a faceted diamond. Newly recovered or newly grown rough still needs processing to acquire the shape and brilliance of a jewellery gem.
Contents
1. What Is Diamond? How Carbon Becomes a Crystal
Diamond is a crystalline form of carbon. Its atoms form strong bonds in a three-dimensional lattice, giving diamond its high hardness and distinctive optical properties. Graphite is also made of carbon, but its atoms are arranged differently, so its properties differ. Having carbon available does not automatically produce diamond: the carbon must crystallise in the right structure.[1]
Natural and lab-grown diamonds both have the diamond crystal structure. Lab-grown diamonds are not glass or another material made to resemble diamond. Their different growth environments leave different growth patterns, trace elements and defect characteristics, which specialist laboratories can use to identify them. For more on the material and its testing, read Are Lab-Grown Diamonds Real? Material and Identification Explained.
The two origin pathways. Mining or growth is one stage in the journey from rough to jewellery; processing and examination still follow.
2. How Natural Diamonds Form Beneath the Earth
What conditions turn carbon into natural diamond?
Many natural diamonds form in the mantle roughly 150–200 kilometres beneath old, stable continental regions. High pressure and temperature allow diamond to remain stable there, but those conditions are only part of the story. Carbon-bearing fluids or melts and a suitable chemical environment are also needed for carbon to precipitate and grow as diamond. Some diamonds come from much greater depths, so no single depth describes them all.[2]
The carbon in a natural diamond can come from the mantle, and it can also include carbon carried deep into the Earth when surface material is recycled through subduction. The familiar story of coal being squeezed into diamond reduces complex geochemistry to a memorable explanation that does not apply to most jewellery diamonds.[2][20]
Does an ancient diamond grow continuously for a billion years?
Research shows that some natural diamonds are more than three billion years old, while others formed around one to two billion years ago. These ages are generally inferred from minerals enclosed within the diamonds and their isotope records. They do not mean that a crystal grew continuously for that entire period.[3]
A diamond can grow in stages, with interruptions, then remain underground for a very long time before reaching the surface. The age of a diamond, the duration of each growth episode and the date it was carried upwards by volcanic rock are three different questions. There is no fixed formation time that applies to every natural diamond.
Why are diamonds underground so difficult to find?
A diamond also needs a journey that preserves it. Deep-sourced magmas, including those that form kimberlite, can pick up diamonds that already exist and rise rapidly towards the surface. These volcanic rocks act as carriers. Later weathering and river erosion can move diamonds into riverbeds, coastal deposits and seabed gravels.[4]
An economically viable diamond deposit therefore needs the right crystallisation conditions, a geological history that preserves the crystals, a route towards the surface and a sufficient concentration of diamonds. Finding kimberlite does not guarantee enough diamonds for commercial mining. Natural supply is constrained by geology: a mine can adjust output, but it cannot turn a diamond-poor rock body into a rich deposit.[20]
3. How Mines Find and Recover Natural Diamonds
Before mining begins, geological teams use geophysical surveys, core drilling and sample analysis to model the ore body. They estimate the amount of ore, its diamond grade and the value that could be recovered before deciding whether a mine is viable. The technical challenge is to find the right deposit, design safe extraction methods and recover a small quantity of diamonds intact from a large quantity of rock.[5]
Four common mining methods
Open-pit mining: where the ore body is close to the surface, teams excavate in stages. Drilling rigs, controlled blasting, large excavators and haul trucks move diamond-bearing ore to a processing plant. Slope stability, drainage and waste-rock management require continuing engineering work.
Underground mining: when an ore body extends deeper, some mines use shafts, tunnels and underground extraction systems. Beyond the machinery, they need rock-mechanics analysis, ground support, ventilation, drainage and transport infrastructure. The extraction method depends on the ore body and surrounding rock.
Alluvial mining: erosion releases diamonds from their original host rock and concentrates them in riverbeds or gravel layers. Recovery ranges from manual washing to mechanised excavation, screening and gravity separation. Scale and management practices vary considerably.[6]
Marine mining: diamonds occur in seabed gravels off Namibia. Mining vessels combine seabed crawlers, pumping systems and onboard processing facilities to recover material. The next-generation crawler announced by Debmarine Namibia in 2025 weighs 370 tonnes, illustrating the scale of engineering involved in offshore recovery.[7]
Extracting the rock is only the beginning
Processing plants crush, screen and sort material according to its characteristics. Dense-medium separation uses differences in mineral density to concentrate the diamond-bearing fraction. X-ray transmission sorting, or XRT, uses transmission characteristics to identify candidate material. Some mines recover large diamonds early in the process to reduce the risk of valuable rough entering later crushing equipment.[5]
These systems must be calibrated for particle size, mineral composition and recovery objectives. Inappropriate crushing can damage rough diamonds, while poorly calibrated sorting can miss them. Recovered diamonds are still rough: sorting, cutting plans, cutting, polishing and examination are needed before they become the faceted gems seen in jewellery displays.
4. Where Natural Diamonds Are Mined Today
From Indian rivers to modern large-scale mines
The earliest known history of diamond collection and trade is associated with river gravels in ancient India. GIA notes that some historical research dates Indian diamond trade to the fourth century BCE. Surviving evidence cannot establish the exact date of the world’s first diamond mining, much less identify the first diamond a person discovered.[6]
Brazil became an important source in the eighteenth century. Discoveries in South Africa in the second half of the nineteenth century then encouraged large mines and industrial supply chains. Diamonds gradually moved beyond royal and wealthy collections into a broader jewellery market. Their cultural meaning comes partly from naturally formed rare crystals, and partly from history, trading systems and jewellery design.
The distribution of global natural diamond production
As of October 2026, the latest complete annual global summary publicly available from the Kimberley Process covers 2025. Natural rough diamond production that year was approximately 98.82 million carats. Russia, Botswana, Angola, Canada and the Democratic Republic of the Congo were the five largest producers by weight; South Africa, Zimbabwe and Namibia were also important sources.[8]
Rough production measures recovered weight. It is not an estimate of how many diamonds remain in the Earth, and it cannot be converted directly into an equal weight of finished jewellery diamonds. Annual output also depends on maintenance, mining plans, inventories and demand. A change in production alone cannot tell us whether diamonds are about to run out.
Origin also depends on which stage you mean. A natural diamond mined in Botswana may be cut and polished in India, then exported through another trading centre. The mining country, manufacturing country and exporting country answer different questions. A country on export paperwork cannot automatically be treated as the rough diamond’s place of origin.
Natural rough diamond production in 2025, showing the major sources ranked by weight. The figures include rough of different qualities and are not finished gem-quality output.
5. The Costs and Effects of Natural Diamond Mining
How much does it cost to recover a carat?
Mines generally calculate unit costs using the total weight of recovered rough, rather than treating every diamond as an equally valuable jewellery gem. De Beers’ published results for the first half of 2026 provide a concrete example:[9]
De Beers reporting scope | H1 2026 unit cost US dollars per recovered rough carat |
|---|---|
Group | $64 |
Botswana operations | $23 |
Namibia operations | $256 |
South Africa operations | $85 |
Canada operations | $37 |
These figures describe the group and its relevant operations; they are not national averages for every mine in those countries. The measure divides operating costs by recovered carats, excluding depreciation and operating special items. It also excludes the full jewellery retail chain. A figure of US$64 per carat is therefore not the total cost of a finished one-carat diamond with a specified colour and clarity.
Ore grade, mining depth, waste rock that must be moved, energy, maintenance and recovery efficiency all affect costs. Fixed infrastructure costs are spread over output, so shutdowns or lower production can increase the cost per carat. Cutting losses, grading, transport and retailing add further stages between rough and jewellery.
What effects does mining leave behind?
Land-based mines can change landscapes and habitats, generate waste rock and tailings, and use water, fuel and electricity. Marine recovery involves seabed disturbance. Actual effects depend on the mining method, scale, local ecology, waste management and rehabilitation arrangements. Different mines should not be treated as having identical effects.[10]
The natural diamond industry also supports employment, technical training and income in producing countries. How those benefits are distributed, whether workers are protected, how mines consult communities and what happens to land after closure are all part of the origin story. Knowing the country alone does not answer those questions.[11]
6. The Starting Point of Lab-Grown Diamonds: Seeds and Carbon
What is a diamond seed?
The growth of a gem-quality single-crystal lab-grown diamond usually begins with a small diamond seed. The seed already has the atomic arrangement of diamond and provides a template for newly added carbon. It is not a plant seed, and it does not create new carbon by itself.[12]
Seeds can come from natural diamonds or from diamonds previously grown by HPHT or CVD. Preparing one involves selecting an appropriate crystal and orientation, cutting it to a suitable size, and polishing and cleaning the growth surface. Its dimensions, surface quality and existing defects can all affect subsequent growth.[13]
If the seed is already diamond, where did the first diamond come from?
Early growth experiments could use natural diamonds as seeds. Today, previously grown diamonds can be processed into new seeds, continuing the production chain. This supplies a starting point for the next batch, but every batch still needs new carbon feedstock.
In common HPHT processes, new carbon primarily comes from solid sources such as graphite. In common CVD processes, it comes from carbon-containing gases such as methane. The additional diamond weight mainly consists of carbon from those materials crystallising on the seed. The seed provides the starting point, the equipment provides the environment and the feedstock provides the material. A seed does not become a larger diamond from nothing.[19][16]
Illustration of thin diamond seed plates and a separate, larger rough crystal. These are different samples, not an actual before-and-after comparison of the same seed.
7. How Lab-Grown Diamonds Moved from Industry into Jewellery
What equipment do the two growth methods need?
HPHT uses high-pressure, high-temperature equipment, with a carbon source, metal flux and seed placed in a growth assembly. Typical conditions are around 5–6 GPa and 1,300–1,600°C. Carbon dissolves in the metal medium and then crystallises on the seed under a suitable temperature gradient. Pressure equipment, heating and control systems, and a stable growth recipe are essential.[19]
CVD uses a low-pressure growth chamber, vacuum pumps, gas-flow controls, heating and energy systems such as microwaves. These activate carbon-containing gases so that carbon deposits on the diamond surface in layers. Both methods require precise control and testing. Engineers must continually manage temperature, gas or pressure conditions, as well as impurities that can affect colour and quality.[16]
For the differences between the methods, read CVD and HPHT Lab-Grown Diamond Technology Explained. For the full sequence from seed preparation and growth to cutting, polishing and examination, see How Lab-Grown Diamonds Are Formed: From Seed to Finished Gem.
The earliest lab-grown diamonds were not made for rings
Laboratory diamond growth predates its widespread use in jewellery. GIA’s technical history records that William Eversole grew tiny diamonds using an early CVD method in 1952. Sweden’s ASEA achieved high-pressure synthesis in 1953 without announcing it at the time. In 1954, General Electric achieved reproducible HPHT diamond synthesis, helping develop diamond as an industrial material.[14]
Early products mainly served abrasive and cutting applications. Around 1970, GE produced crystals that could be cut into jewellery gems; those results were published in 1971. Moving from making diamond to consistently producing suitable jewellery sizes, colours and clarity required many further improvements.[1][14]
Where are they grown, and where are they exported?
China, India and the United States all produce lab-grown diamonds. China’s HPHT sector has strong links with industrial diamond technology, while India has developed a chain spanning CVD growth, cutting, polishing and exports. These regions are not limited to a single growth method.[13]
India’s GJEPC reported approximately US$1.13 billion in polished lab-grown diamond exports for the 2025–2026 financial year. This indicates the scale of its trading and manufacturing role. It cannot be converted directly into global growth output, nor does it establish that every exported diamond was grown in India.[15]
Lab-grown diamonds can also cross borders: grown in one place, cut in another and exported through a trading centre. Tracing origin requires information about the grower and production batch. A gemmological report can establish the diamond’s category, but not every report is a complete record of its manufacturing origin.
8. Lab-Grown Diamond Production Costs and Environmental Effects
Production costs include making each batch succeed consistently
Carbon feedstock is only one part of production costs. High-pressure equipment or CVD reactors, energy, seed preparation, gases and consumables, maintenance, technical staff and quality testing all contribute. Post-growth treatment, where needed, and losses during cutting can increase the cost of acceptable finished gems.
That is why one growth cost per carat cannot represent the whole industry. A factory can calculate its own costs from batch inputs and acceptable output, but equipment scale, electricity prices, crystal quality, manufacturing goals and yield vary. Rough growth costs, polished wholesale prices and jewellery retail prices also cover different stages.
A controlled environment still has growth limits
Gem-quality diamonds commonly require weeks of growth, and larger or more demanding crystals may take longer. The actual duration depends on the process and target. GIA notes that HPHT growth times range from short periods for small products to weeks. Large, highly pure, colourless crystals require tighter impurity control and sustained growth conditions.[13]
Growth can introduce non-diamond carbon, impurities or metal inclusions, and can also create stress, fractures and unwanted colour. A faster growth rate does not necessarily deliver more usable material. Running equipment for longer does not guarantee a large rough crystal suitable for cutting.[16][19]
The challenge of scaling production is to keep equipment and recipes producing crystals that meet the target. A record-size crystal and consistent high-volume production present different technical demands. Read How Large Can a Lab-Grown Diamond Be? for more on size limits and the challenges of large crystals.
Environmental effects depend on the actual production process
Lab-grown diamonds reduce the need for the extraction stages involved in obtaining natural diamonds. However, growth equipment still consumes energy, and production also involves cooling, gases, equipment manufacture and subsequent processing. The electricity mix, energy used per batch and acceptable output affect actual environmental performance. Laboratory growth alone does not demonstrate zero emissions or zero environmental impact.[17]
Comparisons need a consistent scope. Do the figures include feedstock, equipment, growth or mining, cutting and transport? Do they compare a carat of rough or a carat of acceptable finished gems? Selecting one factory or mine and using its figures to characterise an entire category can produce a misleading conclusion.
Their wider effects extend beyond jewellery
Natural diamonds connect geological time, places of origin and mining communities. Lab-grown diamonds bring diamond into repeatable production and engineering design, adding another material source to jewellery. This change affects growers, manufacturers and communities dependent on mining, extending beyond a buyer’s budget.
Growth technology also serves applications outside jewellery. Research directions announced by India’s IIT Madras in 2026 include quantum sensing, photonics and electronic materials. These uses have specific requirements for purity, defects or doping, which may differ from jewellery priorities for colour and clarity. Diamond is both a gem material and an engineering material that can be designed with precision.[18]
9. Comparing the Origins of Natural and Lab-Grown Diamonds
Placed side by side, the clearest distinction is this: natural diamonds require us to find crystals that the Earth has already formed and preserved; lab-grown diamonds require new carbon to grow as diamond in a controlled environment. Both still need rough processing, examination and supply-chain management before reaching the jewellery market.
Comparison | Natural diamonds | Lab-grown diamonds |
|---|---|---|
Material | A diamond crystal made of carbon | A diamond crystal made of carbon |
Carbon source | Carbon-bearing mantle fluids or melts; may include carbon carried down by subduction | Usually solid carbon sources such as graphite, or carbon-containing gases such as methane |
Place of crystallisation | Natural geological environments deep within the Earth | HPHT or CVD growth equipment |
Growth starting point | Crystallisation and further growth in a natural environment | Usually a seed that already has the diamond structure |
Understanding time | Crystal age, growth episodes and transport to the surface are distinct | Growth cycles are measured in days, weeks or longer, depending on the target |
Obtaining rough | Mining and recovery from rock, river deposits or seabed gravels | Recovery from growth equipment, with post-growth treatment when needed |
Main supply constraints | Viable deposits, diamond grade, mine life and recovery conditions | Equipment capability, recipes, seeds, growth rate and acceptable yield |
Key costs | Exploration, extraction, ore processing and mine operations | Equipment, energy, seeds, consumables, process control and quality management |
Environmental considerations | Land or seabed disturbance, waste, water, energy and rehabilitation | Energy, electricity mix, equipment, consumables and growth yield |
Questions for traceability | Which mine recovered it, and which processing and trading stages followed? | Which grower made it, using which method, and which processing stages followed? |
Understanding origin helps us appreciate a diamond more accurately. A natural diamond’s appeal can lie in its geological history and individual characteristics. A lab-grown diamond demonstrates our ability to control crystal growth. Both are diamond; the distinctions worth understanding concern how they form and the production and supply chains behind them.
At RAGAZZA, we believe a choice should begin with clear information: the diamond category should be explicit, quality and grading information should match the actual product, and origin and environmental claims should be supported by evidence.
Explore RAGAZZA’s introductions to natural diamonds and lab-grown diamonds, then compare options against your design, quality requirements and budget.
Sources
The original research, statistics and institutional publications cited in this article are listed below. Production figures cover the full year 2025; mining cost figures use published results for the first half of 2026.
