# Forminière The diamond parastatal of the Kasai, founded in the autumn of **1906** — and the concrete refutation of the idea that the Congo was purely a Belgian affair. Its ownership at founding: **[[Leopold II]]'s Foundation of the Crown and the Congo Free State 58%**; **American investors led by Thomas Fortune Ryan and Daniel Guggenheim 25%**; Société Générale de Belgique and other Belgian investors 17%. **American capital was inside Leopold's Congo from 1906**, through the same financiers who built Wall Street's mining and railroad fortunes, with a sibling vehicle called the American Congo Company. That is a useful corrective whenever the Congo Free State is discussed as a purely European crime. Prospectors collected samples near **Tshikapa** in 1907; diamonds were confirmed by about 1909, and a second major field was found at **Bakwanga** in 1918. Forminière held the Kasai diamond monopoly until 1961 — 425,234 carats in 1959, some 15,000 workers by 1958 — and at its height the Congo was the world's leading producer of industrial diamonds. Operations at Bakwanga ceased in **January 1962**, taken over by the new state-majority **MIBA**; Forminière itself was wound up in **1966** in the Mobutu-era nationalisations. Kasai is also the region of Albert Kalonji's South Kasai secession of 1960–62 — the diamond twin of Katanga's copper secession. See [[Katanga Secession]]. MIBA has since largely collapsed, and Kasai diamond production is now dominated by informal alluvial diggers — the same transition from industrial to artisanal documented across the Congolese mining economy on [[Gécamines]] and [[Artisanal and Small-Scale Mining]]. ## See also [[Belgian Congo]] · [[Union Minière du Haut-Katanga]] · [[Kilo-Moto]] · [[Congolese History Hub]] · [[Conflict Minerals Hub]]