When one sits back and thinks about the liquid fuels that are required to keep shipping and mining the ever decreasing mineral concentrations one has to ponder at what point will shipping and mining costs exceed the economic value of the minerals to society. How will the mineral economic value to society be determined? Which minerals will be the ones that will be the most valued in the future? It will be interesting to see which decline start first mineral depletion or liquid fuels as they are terminally linked. The most important minerals will ultimately end up being those essential to food production.

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