The value they have is usually only realized, however, when they are exploited, that is, dug out of the ground, processed or refined.
Natural resources are a necessary ingredient of all economic activity.
Natural resources can be of three types. The second is renewable , like water and fish, which are reproducible. An example is a landscape of outstanding beauty, which yields utility for those that see it, and tourist income for the owner. See environmental economics . The Penguin Dictionary of Economics 2.