In February 2026, landslides collapsed several artisanal coltan mines near Rubaya in North Kivu province, eastern Democratic Republic of Congo. At least 227 miners were killed. The Rubaya mines are controlled by M23 — a rebel militia backed by Rwanda and Uganda — which seized the site in 2024 and generates an estimated $800,000 per month from mineral extraction to fund its insurgency. UN experts report that more than 120 tonnes of coltan are transported monthly from the DRC into Rwanda, where it is laundered and exported as Rwandan product to smelters in China, Europe, and the United States. The coltan is processed into tantalum — a heat-resistant metal with a melting point of 3,290°C — and manufactured into the tiny capacitors inside every smartphone, laptop, game console, medical pacemaker, and automotive control unit on the planet. A single smartphone contains 30 to 60 milligrams of tantalum. With 1.2 billion smartphones shipped annually, that single application consumes 36 to 72 metric tonnes — roughly 5% of total global production. In December 2024, the DRC filed an unprecedented legal case against Apple, accusing its Belgian and French subsidiaries of using conflict minerals that fuel violence in eastern Congo. Apple reported $112 billion in net profits that year. The tantalum in one of its phones is worth a few dollars.
What tantalum does
Tantalum’s industrial value comes from a combination of properties that no other element replicates at the same scale and cost. A melting point of 3,290°C — exceeded only by tungsten and rhenium. Exceptional corrosion resistance — tantalum is virtually inert to hydrochloric acid, sulfuric acid, and most organic acids below 150°C, which is why it lines chemical processing equipment and surgical implants. And the property that makes it indispensable to the electronics industry: tantalum forms a thin, stable oxide layer that functions as an extraordinarily effective dielectric, enabling capacitors that are smaller, more reliable, and more thermally stable than any alternative.
Tantalum capacitors operate at temperatures exceeding 200°C, making them essential for processors, memory modules, and power management circuits in smartphones, laptops, data centers, and automotive electronics. They are the reason modern electronics can be as small as they are — the capacitor that regulates voltage in your phone’s processor is a tantalum component measured in fractions of a millimeter. Beyond electronics: tantalum is alloyed into nickel-based superalloys for jet engine turbine blades (the same high-temperature aerospace applications where rhenium and samarium cobalt magnets operate), used in armor-piercing military projectiles, and deployed in surgical implants — hip replacements, cranial plates, wire sutures — because the human body does not reject it.
Where it comes from
The DRC leads global tantalum production, accounting for over 37% of the world’s output. Rwanda is second. Brazil third at 22%. Australia, which once dominated production, has largely withdrawn — its largest mine, Wodgina, shifted to lithium spodumene production when lithium prices made the conversion economically irresistible. Artisanal and small-scale mining collectively accounts for an estimated 64% of global tantalum production — the highest artisanal proportion of any critical mineral in the Rare Earth Elements course.
The DRC-Rwanda corridor is the supply chain’s defining feature and its deepest problem. North Kivu province contains an estimated 80% of the DRC’s coltan reserves, making it a strategic chokepoint for global tantalum supply. The Rubaya area alone accounts for roughly 15% of global coltan output. M23 and approximately 10,000 Rwandan troops control the extraction, trade, and smuggling of minerals from Rubaya. Artisanal miners — approximately 40,000 in the broader North Kivu region — earn $3-5 per day extracting material worth hundreds of dollars per kilogram on international markets. The ore is carried across the border into Rwanda, where it enters the legitimate supply chain as “Rwandan production.” Rwanda’s mineral export revenues tripled from $373 million in 2017 to over $1.75 billion in 2024 — a growth rate that, as multiple UN investigations have noted, far exceeds what Rwanda’s domestic mineral deposits could plausibly explain.
The laundering operation is structurally identical to the commodity-laundering schemes the Shadowcraft course documents across multiple case studies — Marc Rich moving sanctioned oil through shell companies, BCCI moving funds through layered accounts, Mossack Fonseca providing the corporate shells. The DRC coltan trade uses Rwanda as its laundering jurisdiction: conflict-origin ore enters Rwanda, is relabeled as Rwandan production, is exported to smelters in China and Southeast Asia, is processed into tantalum powder, is manufactured into capacitors by KEMET, Vishay, AVX, and other component manufacturers, and appears in the products of Apple, Samsung, Intel, and every other electronics company on Earth. The supply chain has 6-8 intermediary steps between the mine where 227 people died in February 2026 and the phone in your pocket.
The compliance architecture
The global response to tantalum’s conflict mineral status has produced one of the most elaborate compliance frameworks in the critical minerals landscape — and one of the least effective at changing what happens on the ground.
The 2010 Dodd-Frank Act, Section 1502, required U.S.-listed companies to audit their supply chains and report to the SEC whether their products contained tin, tantalum, tungsten, or gold — the “3TG” conflict minerals — sourced from the DRC or adjoining countries. The EU’s Conflict Minerals Regulation, effective since 2021, requires importers of 3TG to conduct due diligence on their supply chains. The OECD Due Diligence Guidance provides the international framework. Smelters can be audited and certified as “conflict-free” through the Responsible Minerals Initiative’s Responsible Minerals Assurance Process. Intel publicly committed to conflict-free processors in 2012 and conducted third-party audits of all its smelters. KEMET, the world’s largest tantalum capacitor manufacturer, established a “closed-pipe” supply chain from its Kisengo mine in Katanga province to its processing plant in Matamoros, Mexico.
The compliance infrastructure exists. The conflict minerals trade continues. M23 controls Rubaya. Rwanda launders the output. Smelters in China process ore whose chain of custody is, in many cases, impossible to verify. The Dodd-Frank reporting requirement was weakened under the Trump administration in 2017. The compliance adds 2-8% to project budgets, which legitimate operators absorb and conflict operators avoid. The structural problem is that tantalum from Rubaya is chemically identical to tantalum from Brazil — once it’s been smelted, no analytical technique can distinguish conflict-origin metal from certified-clean metal. The compliance framework is built on paperwork. The laundering operation is built on chemistry.
Why it’s in the course
Tantalum is the Rare Earth Elements course’s most direct intersection of critical minerals, armed conflict, and consumer electronics. The cobalt/coltan post introduced the conflict minerals framework across the DRC’s mineral economy. This post goes deeper on a single element — the one where the mine-to-phone supply chain is most documented, most laundered, and most directly connected to an active military conflict funded by the mineral itself.
The antimony supply chain vulnerability is about Chinese export controls. The terbium supply chain vulnerability is about Chinese separation monopoly. The nickel supply chain vulnerability is about Indonesian resource nationalism. Tantalum’s vulnerability is different from all of those: 64% of global production is artisanal, a significant fraction is controlled by an armed rebel group, the laundering infrastructure has been documented by UN investigators for two decades, and the compliance framework designed to address it cannot distinguish clean metal from conflict metal once it’s been smelted. The supply chain isn’t concentrated in one country the way gallium or graphite is. It’s concentrated in one conflict zone, with one laundering corridor, funding one war — and the metal that comes out the other end is inside the device you’re reading this on.
This is the kind of supply chain our Rare Earth Elements course was built to map — where a capacitor smaller than a grain of rice depends on a metal mined by hand in a war zone, laundered through a neighboring country, smelted into anonymity, and soldered into 1.2 billion phones a year by companies whose compliance paperwork says the supply chain is clean.