Niobium is a metal that we frequently use here for its superconducting properties (Tc = 9.3 K). At lunch today we were wondering where it comes from: are there niobium mines somewhere? Perhaps, I suggested, it is mined in Africa under highly exploitative conditions, and we’ll find protestors picketing the lab for our use of blood niobium.
Turns out this is disturbingly close to the truth:
Coltan is the colloquial African name for (columbite-tantalite), a metallic ore comprising niobium and tantalum.
Coltan smuggling has also been implicated as a major source of income for the military occupation of Congo. To many, this raises ethical questions akin to those of conflict diamonds. Owing to the difficulty of distinguishing legitimate from illegitimate mining operations, several electronics manufacturers have decided to forgo central African Coltan altogether, relying on other sources.
On the other hand, it looks like coltan is more important as a source of tantalum, and most niobium comes from Brazil and Canada. So probably our research isn’t built on slave labor and exploitation (postdoc salaries aside).