Some minerals are very rare and some exist in great quantities, but--for
practical purposes--the ability to recover them is just as important as
their abundance. As minerals are depleted, obtaining them becomes more
difficult. Recycling and the development of substitutes can reduce the
rate of depletion but may also be costly.
| NSES Content Standard F
Science in Personal and Social Perspectives: Natural resources Grades 9-12, page 198 The earth does not have infinite resources; increasing human consumption places severe stress on the natural processes that renew some resources, and it depletes those resources that cannot be renewed. |