Raw Material Time Horizons

Based on a recent United States Geological Study, Lester Brown informs us that we will exhaust known stores of several vital metals within the next two to three generations, based on a reasonable estimation of 2% growth in extraction. While recycling efforts have accelerated, virgin materials are still being harvested at an alarming rate.What will the world be like when we have run out of copper or steel? The average building today relies upon a great quantity of these resources for its construction. Faced with these facts, we can easily imagine a future in which industry has completely re-engineered its handling of material resources. After all, there seems to be no other choice.