Five Major Suppliers Push Rough Supply into Uncharted Territory

Angola’s declaration of its 2025 diamond production and exports highlights just how much the rough market has changed.

Today, five groups shape the diamond market: De Beers, Alrosa, Angola, Okavango Diamond Company and the tender houses. That marks a clear shift from its historic structure.

De Beers (in)famously controlled supply for about a century, largely through its agreement to market Russian production. Regulators finally broke that arrangement up in the early 2000s, bringing Alrosa to market as an independent major seller. Its production soon surpassed that of De Beers as the latter streamlined its portfolio and leaned into branding in the 2010s. At one stage, Rio Tinto might have been grouped among the “majors,” but it kept a relatively low profile in diamonds and recently closed its final operation.

De Beers and Alrosa significantly influenced the market environment that decade, largely through their respective supply and pricing decisions, often moving in step in response to volatile conditions. Given how closely aligned they were, the market still operated with a degree of tacit control, for lack of a less provocative description.

At the same time, more junior and mid-tier miners began selling a greater share of production through auctions and tenders, outsourcing much of that activity to specialist tender houses. Meanwhile, De Beers was deemphasizing the role of the rough dealer, discouraging sightholders from trading boxes on the secondary market. Individual rough trading diminished, and the tender circuit effectively replaced the dealer market.

Botswana added another layer. In the 2010s, the government established Okavango Diamond Company (ODC) to sell 15% of Debswana’s production, its joint venture with De Beers, via tenders as part of its beneficiation strategy. That share has since risen to 30% under the current agreement and is set to reach 50% in the next decade. The shift has been significant enough for ODC to begin introducing contract sales.

Angola has also stepped forward. Production has increased as exploration picked up after years of limited activity. While the Catoca mine is expected to wind down toward 2037, the Luele mine, launched in 2024, last year surpassed Catoca as the country’s largest producing mine. Angola has also become a focal point for new exploration, attracting investment from De Beers and Rio Tinto.

Angola’s rough diamond production rose 8% to 15.19 million carats in 2025, according to the Ministry of Mineral Resources, Petroleum and Gas. Exports reached 17 million carats, valued at $1.6 billion.

Where supply was once managed by one, and later two, entities with a shared objective of balancing the market, it is now spread across five players with different agendas and approaches.

De Beers still carries elements of its historic leadership role, offering sightholders flexibility during weaker demand. However, its influence of doing so last year was less apparent as the rough market remained under pressure despite those efforts. At the same time, De Beers is narrowing its focus, prioritizing select partnerships rather than a broad client base.

ODC may lean in a similar direction, though as a state-backed entity it also faces pressure to generate revenue. Angola and Alrosa sit more clearly in that category. Both are government-linked and focused on moving volume, even when market conditions are not supportive, as Angola’s latest figures suggest.

The tender circuit operates differently. It is made up of independent players selling run-of-mine goods through competitive bidding, with prices driven directly by prevailing demand.

This fragmentation of supply should, in theory, be a positive development. It introduces competition and weakens any lingering perception of cartel-like control. It also shifts the power dynamic toward manufacturers, giving them more scope to refuse goods and placing greater responsibility on miners to manage inventory, rather than leaving that burden largely with manufacturers as it was over the past decade or two.

The timing, however, is unfortunate. The market currently needs discipline, not additional volume, particularly when demand is increasingly segmented and leaving large portions of production under pressure.

That makes the transition more complicated for newer participants such as ODC and Angola, both of which are in the midst of elevating their roles. It also adds another layer of complexity for De Beers, which is heading toward new ownership, and for Alrosa, which continues to operate under G7 sanctions.

It will be fascinating to watch how the different models play out, and the extent to which the broader diamond industry is affected. The rough market is entering a new phase in which it will operate according to a very different set of rules. With five majors in rough supply, the old playbook no longer applies.

Image: Rough diamonds. (Alrosa)