An assessment of metal supply sustainability as an input to policy: security of supply extraction rates, stocks-in-use, recycling, and risk of scarcity

The integrated model WORLD and Hubbert's model were used for assessment of future supply for different metals: iron, nickel, manganese, chromium, molybdenum, tantalum, niobium, rhenium, zirconium, tungsten, cobalt, copper, zinc, lead, aluminium and the technology metals derived from copper-zinc mining (tellurium, selenium, gallium, indium, antimony, bismuth, tin, germanium, selenium). The connections between their productions were mapped. The literature was reviewed for best estimates of total recoverable amounts, and best estimates were made, considering extraction costs and extractability. Peak years were determined for all the metals studied. Most metals seem to reach peak production during the next 4 decades, suggesting a risk for shortages in the near future. When supplies from mines dwindle, measures such as recycling from society's stock, substitutions to other materials than metals when this is possible, and stopped dissipative uses, will become important mitigation tools, calling for reorganization of resource policies world-wide. Present resource policies at all levels (regional, national, international) are to a large degree inadequate and need thorough review. The relevance of the Hubbert's model as an assessment tool was done. It is useful for all metals taken from independent ore deposits, whereas the method appears to be less suited for extraction of dependent metals unless the curve is derived from the Hubbert's model applied on the parent source. In such times, strategic thinking and strategic leadership based in systems thinking will be required.