Indeed. Which in practical, commercial terms is semi-infinite, since commercial mining does not involve a never-ending search for additional potential sources o

Indeed. Which in practical, commercial terms is semi-infinite, since commercial mining does not involve a never-ending search for additional potential sources of material, only the mid- to long-term sufficient exploration and development of economically feasible sources. Where mid-term could mean approximately one human generation, and long-term a human lifetime. Another example of such long-range planning in commercial ventures is the lumber business in North America and Scandinavia (that I know of), deliberately and systematically re-generating forests for continued harvesting while keeping their sight on a 80-100 year horizon.