Ethical diamonds: traceability and the Kimberley Process

The diamond trade has long been shrouded in shadows. Wars financed, mines exploited, certificates forged. Since 2003, the Kimberley Process has worked to close one door: that of conflict diamonds. An international certification system that today spans 85 countries. It has its acknowledged limitations. Yet it remains the industry's minimum safeguard, and every Mayuri diamond meets its standards. Here is how it works, what it protects, and what it does not cover.

A certification system that excludes conflict diamonds from legal international trade. Established in 2003, it now unites 85 producing, processing, and importing countries. The principle is straightforward: each parcel of rough diamonds crosses a border accompanied by a Kimberley certificate, an official document stamped by the authorities of the country of origin, attesting that the stones do not come from a conflict zone.

The Kimberley Process covers rough diamonds only, before cutting. Once a diamond has been cut, it falls outside the scope of the system. The certificate follows the parcel, not the individual stone. This is collective traceability, not individual traceability. If a parcel of 10,000 carats crosses a border with its certificate, each of those carats is considered compliant. However, tracing a specific diamond from that parcel once it has been cut and set becomes impossible.

The name comes from Kimberley, a mining town in South Africa, where the first negotiations took place in 2000. The goal was clear: to cut off the financing of civil wars in West Africa through the diamond trade.

The 1990s saw the rise of the term blood diamonds. In Sierra Leone, Angola, and the Democratic Republic of Congo, rebel movements financed their wars by seizing control of diamond mines. Militias engaged in forced recruitment, mutilated civilian populations, and exploited workers with no protection. The extracted stones were sold on the black market and then absorbed into legal supply chains, often through compliant intermediaries.

The humanitarian toll was devastating. In Sierra Leone, the conflict claimed 50,000 lives between 1991 and 2002. Diamonds extracted from rebel-held zones financed arms purchases and prolonged the conflict. Angola faced a similar situation: the UNITA rebellion controlled diamond deposits and generated hundreds of millions of dollars per year. The international community took years to respond.

The Kimberley Process was adopted in 2003, following three years of negotiations between governments, NGOs (notably Global Witness and Partnership Africa Canada), and the diamond industry. It was a belated response, but a necessary one. The system came into force in January 2003 with 37 signatory countries. Today, 85 countries are members, representing approximately 99.8% of global rough diamond trade.

At the heart of the system is the Kimberley certificate, an official document that accompanies each parcel of rough diamonds during a cross-border transfer. This certificate includes:

• The origin of the parcel (producing country)
• The total weight in carats
• The estimated value
• The number of parcels
• A unique serial number

The authorities of the exporting country issue the certificate, seal it, and stamp it. At the border, customs officials of the importing country verify the certificate and confirm that the seal has not been broken. If everything is in order, entry is authorised. If the certificate is missing, or if the seal is broken, the shipment is seized.

Each participating country establishes a designated national authority. In France, this is the Directorate General of Customs and Indirect Taxes. In the United States, the US Census Bureau. In Belgium (Antwerp, the world's diamond hub), it is the Federal Public Service Economy. These authorities exchange data with one another, feeding a centralised database of issued certificates.

The penalties for violations are severe. A country that fails to meet the requirements may be suspended from the system. This means it becomes impossible to export or import rough diamonds to or from other participating countries. Venezuela was suspended in 2019 for non-compliance with certification procedures. The Central African Republic has experienced several partial suspensions.

The Process also relies on peer review missions. Every three years, each participating country receives a visit from an international delegation that inspects its implementation: customs controls, certification procedures, and lot traceability. If the shortcomings are too significant, the country risks suspension.

The system has a limited scope. It covers only diamonds extracted in areas controlled by rebel groups financing a war. If a diamond comes from a mine operated by a legitimate government, even if working conditions are dire or the environment has been devastated, it remains eligible for the Kimberley certificate. The Process says nothing about workers' rights, river pollution, child labour, or human rights violations outside the context of armed conflict.

Amnesty International and Global Witness have criticised this overly narrow scope. In 2011, Global Witness withdrew from the Kimberley Process in protest, arguing that the system was failing to adapt to new forms of diamond-related violence, including state violence and civilian massacres in government-controlled mining areas. Zimbabwe is a telling example: in 2008, the Zimbabwean army violently suppressed artisanal miners in the Marange diamond fields, killing more than 200 people according to Human Rights Watch. Yet Zimbabwe remains within the Kimberley Process, as the conflict does not qualify as a rebel insurgency in the strict sense.

Another limitation is that traceability stops at the border. Once a batch has been imported, the Kimberley certificate no longer tracks anything. The batch can be mixed with others, cut, and redistributed. If a corrupt intermediary introduces uncertified diamonds into a certified batch after it enters the country, no Kimberley mechanism can detect it.

Finally, the system relies on the good faith of states. Some producing countries have weak institutions and porous controls. Certificates can be forged and batches relabelled. NGOs regularly document these flaws. The Kimberley Process is a safeguard, not an absolute guarantee.

The Kimberley Process sets a minimum threshold. But diamond ethics continue to evolve. Consumers want to know where their stone comes from, who mined it, and how it was cut. Several initiatives go further.

Blockchain technology enables stone-by-stone traceability. Companies such as Everledger and Tracr (an initiative by the De Beers group) record each diamond on a blockchain from the moment of extraction. A unique identifier follows the stone at every stage: mine, cutting, certification, and setting. This digital traceability goes beyond the Kimberley certificate, which only tracks the raw batch.

The Responsible Jewellery Council (RJC) certifies players across the supply chain, including mines, processors, and jewellers, against social and environmental criteria. Unlike the Kimberley Process, which covers only armed conflict, the RJC audits working conditions, carbon emissions, water management, and respect for local communities. An RJC-certified jeweller commits to sourcing exclusively from suppliers who are themselves certified.

Fairmined, originally developed for gold, is exploring extensions into diamonds. The label guarantees a fair price for miners, decent working conditions, and a strict ban on child labour. It is a social approach that complements the security-focused angle of Kimberley.

As for lab-grown diamonds, they fall outside the Kimberley Process, which certifies only natural diamonds. They carry no mining impact and no conflict risk. However, their production is energy-intensive, sometimes relying on carbon-heavy sources. The comparative ethics of Kimberley- and RJC-certified natural diamonds versus lab-grown stones remains an open debate, with no single definitive answer.

At Mayuri, 100% of our diamonds comply with the Kimberley Process. Batch traceability, diamonds sourced outside conflict zones. This is a required baseline, not an achievement to boast about. We work exclusively with suppliers who document the origin of their stones and submit to Kimberley Process controls.

We also recognise that the Kimberley Process alone is not enough to define an ethical diamond. It excludes conflict diamonds, but says nothing about extraction conditions, environmental impact, or workers' rights. This is why we select our suppliers against broader criteria: environmental commitment, RJC certifications where available, and transparency across supply chains.

Our diamond wedding rings embody this commitment. Solid 18ct gold, Kimberley-certified diamonds, handcrafted in our workshops. Each stone is individually inspected by our gemologists before setting. We uphold this rigour as a mark of respect for the person who will wear the piece. Discover How Does a Diamond Form? From the Earth to the Jewellery Case to understand the complete journey of a diamond, from its geological origins to your finger.