from David Barouski’s 10/19/08 Presentation The most valuable cassiterite deposits in the Congo are found in Walikale Territory. They account for 70% of North Kivu’s cassiterite production. The most coveted deposit in WalikaleTerritory is located in Bisie or, as some researchers denote it, the Mpama/Bisie mine. In addition to cassiterite, Bisie also contains smaller deposits of diamonds, uranium, gold, cobalt, and bauxite (or aluminum) ore.
This speech was given when chaos ruled in the area.
Even at that time Bisie was supplying 4% of the world's tin supply about equivalent to what Mpama NORTH is producing today through artisanal mining.
Cassiterite was discovered as early as 1910 so it is likely that other valuable discoveries like diamonds uranium gold cobalt bauxite have been known as well