Rubaya4 landslides killed hundreds at coltan mines since January.
Rwanda-backed M23 controls the Rubaya mines in Congo, where an estimated 11,000 miners extract coltan for smartphones and electric vehicles.
M23 restricts journalist access; satellite imagery remains the only way to verify casualty counts.
Sources: Bellingcat
WHAT COLTAN IS
Coltan is the ore for tantalum, the metal that makes capacitors small enough to fit in phones. No tantalum, no compact electronics — there is no industrial substitute that hits the same volumetric efficiency.
WHY ARTISANAL
Rubaya's deposits sit in weathered surface soil, not deep hard rock. That makes industrial machinery uneconomic but lets a man with a shovel earn a day's wage. Around 11,000 miners work the hillsides by hand — which is also why a single rain-saturated slope can bury hundreds at once.
THE M23 TAX
M23 doesn't run the mines; it taxes them. Armed groups across eastern Congo have for decades extracted rents at the pit, on the road, and at the border — a pattern UN panels have documented since the late 1990s. Whoever holds the checkpoints collects the rents.
THE RWANDA LAUNDER
Rwanda exports far more tantalum than its own geology can produce. UN Group of Experts reports have repeatedly traced Congolese coltan crossing the border by night, being repackaged as Rwandan-origin, and entering the legal supply chain cleansed of its conflict tag.
WHY DODD-FRANK DIDN'T FIX IT
Section 1502 of the 2010 Dodd-Frank Act required US-listed companies to audit their tin, tungsten, tantalum, and gold supply chains for Congolese conflict sources. Audits checked smelters, not pits — so coltan that entered a smelter labeled Rwandan was certified clean, and the rent to armed groups upstream kept flowing.
THE VERIFICATION GAP
M23 restricts journalist access to the territory it holds, so casualty figures from Rubaya are reconstructed from satellite imagery, displaced-miner interviews, and church-burial records. This is the same forensic stack Bellingcat and the UN Group of Experts now use for most eastern Congo reporting.