Recent studies assert that natural-resource abundance (particularly of minerals) has adverse consequences for economic growth. But these two economists argue that it is inappropriate to equate development of mineral resources with terms such as “windfalls” and “booms.” Contrary to the view of mineral production as mere depletion of a fixed natural “endowment,” they argue that “nonrenewable” resources have been progressively extended through exploration, technological progress, and advances in appropriate knowledge.