There is a category of commodity that sits in a peculiar position in the global economy. Utterly indispensable. Structurally vulnerable. And almost entirely absent from mainstream conversation.
Antimony and coltan belong to this category. They do not feature in the financial press the way lithium or cobalt do. They do not generate the same investor conferences or policy white papers. Yet strip them from the global supply chain and the consequences would be immediate, severe and extraordinarily difficult to reverse.
Understanding why these minerals matter, and why their supply dynamics are so concerning, is not an academic exercise. It is essential context for anyone thinking seriously about the resource economy of the next decade.
Antimony: the mineral inside your defence system, your building and your battery
Antimony is one of those materials whose uses are so varied and so embedded in critical industries that its absence is almost impossible to substitute for quickly. In defence, it is a key component in ammunition, armour-piercing projectiles, night vision equipment and infrared sensors. The United States Department of Defence has formally designated it a critical material for national security. So has the European Commission.
In construction and manufacturing, antimony trioxide is one of the most widely used flame retardants in the world, present in textiles, plastics, electronics casings and building insulation. Remove it from the supply chain and fire safety standards across a vast range of manufactured goods become significantly harder to meet without expensive reformulation.
Perhaps most significantly for the coming decade, antimony is emerging as a key material in next-generation grid-scale energy storage. Antimony-based flow batteries offer longer duration storage than lithium-ion alternatives, making them increasingly attractive for utility-scale renewable energy projects. As the world builds out the storage infrastructure required to make intermittent renewables reliable, demand for antimony is projected to rise substantially.
The supply picture is deeply concerning. China has historically accounted for around half of global antimony production and an even larger share of processing capacity. In late 2024, Beijing imposed export restrictions on antimony, citing national security considerations. The response in Western markets was immediate: prices spiked sharply and procurement teams across defence, electronics and energy scrambled to identify alternative sources.
The uncomfortable truth is that those alternative sources are limited, underdeveloped and largely unprepared to scale quickly. Tajikistan, Russia and a handful of other producers account for most of the remainder. Africa, which holds significant but largely unexploited antimony deposits, represents one of the most credible long-term alternatives, but developing those deposits to production scale will require investment, infrastructure and the kind of patient, operationally capable partnerships that are still rare in the sector.
The window to act is open. It is not permanently so.
Coltan: the invisible foundation of the digital economy
Open any smartphone. Look inside any laptop. Examine the components of any advanced weapons guidance system or satellite. In virtually every case, somewhere inside that device is a tantalum capacitor, and that tantalum almost certainly originated as coltan ore mined in central Africa.
Coltan is a contraction of columbite-tantalite, a metallic ore from which two distinct metals are refined: niobium and tantalum. It is tantalum that drives the demand. Tantalum capacitors are extraordinarily efficient at storing and releasing electrical charge in a minimal physical footprint. They are heat resistant, highly reliable and effectively irreplaceable in miniaturised electronics. The global electronics industry has been built, in significant part, around their properties.
The Democratic Republic of Congo dominates global coltan production, accounting for the majority of world supply. Eastern DRC in particular sits above geological formations of extraordinary richness, not just in coltan but across a range of critical minerals including cobalt, lithium and gold.
The region has been described, with some justification, as the Saudi Arabia of the minerals required for the twenty-first century economy.
The challenge is that a substantial proportion of DRC coltan production takes place through artisanal and small-scale mining, often in areas affected by conflict, with limited traceability and significant exposure to exploitation at the community level.
This has historically made the material difficult for tier-one electronics manufacturers to source with confidence, driving demand for independently verified, chain-of-custody compliant supply.
That demand is growing faster than compliant supply can currently meet. Apple, Samsung, Intel and effectively every major electronics manufacturer now faces binding requirements to demonstrate responsible sourcing across their supply chains. The EU Conflict Minerals Regulation, the US Dodd-Frank provisions and a raft of emerging national legislation have transformed due diligence from a voluntary commitment into a legal obligation.
The commercial opportunity this creates is significant. Platforms that can bring artisanal coltan production into formal, traceable supply chains, verifying provenance and compliance from mine to market, are not just doing the right thing.
They are solving a supply problem that the global electronics industry is actively and urgently trying to address, and that it will pay a meaningful premium to resolve.
Why these minerals matter more than the headlines suggest
Lithium and cobalt have captured the public imagination around critical minerals, partly because of their association with electric vehicles and partly because their price volatility has been dramatic enough to generate financial media coverage. But the strategic significance of antimony and coltan is, in many respects, deeper.
Lithium has multiple potential substitutes under development. Sodium-ion technology is advancing rapidly. Battery chemistries are diversifying. The long-term demand trajectory for lithium, while still strong, carries genuine technological uncertainty.
Antimony and coltan face no such substitution pressure on any near-term horizon. The properties that make tantalum capacitors essential to electronics are not easily replicated.
The role of antimony in defence applications is not a function of fashion or preference. It is a function of physics and engineering constraints that have resisted decades of effort to work around them.
This is why the supply concentration risk in both materials deserves far more serious attention than it currently receives. And it is why the companies building the infrastructure to bring diversified, responsible supply of these materials to market are not simply pursuing an interesting commercial thesis. They are addressing one of the most consequential structural vulnerabilities in the global economy.
This article forms part of Azora Resources’ ongoing commitment to sharing insight on critical minerals, responsible resource development and the role of Africa in global supply chains. Future pieces will explore supply security, upstream investment, government partnerships and the scaling of sustainable mining platforms.
About the Author
Daniel Seal is Executive Chairman of Azora Resources, a global resources and investment platform focused on building scalable, responsible supply chains across Africa and emerging markets.
