Technogenic sources of ore.
From the New York Times story on Siberian pollution. It refers to 3-5 feet of accumulated sludge from the bottom of ponds near nickel smelting plants. The sludge is rich in particles of nickel, copper, and cobalt that were emitted by the smelter and which have settled into the pond through runoff, and contractors have been brought in to harvest the stuff.
Yeah ... those Soviets ... er, Russians ... always quick with a business idea, even as the country sinks into an unliveable environmental hell.
One more problem:
In another problem for a town that has many, pollutants are lowering the freezing point of groundwater, much the way salt scattered on a roadway prevents the formation of ice, said Ali G. Kerimov, a member of the Norilsk City Council.
That is particularly unfortunate here, because the city is built on permafrost, and as foundations once anchored in solid ice shift and crack, buildings become uninhabitable. Mr. Kerimov said 70 out of 1,000 buildings in Norilsk had been forcibly abandoned.
We're on our way to hell.