Diamonds are natural resources. Diamonds are hard to find. They are hidden below Earth's surface. They must be mined, or dug up, before they can be used. Diamonds take many years to form.
Diamonds are an example of a nonrenewable resource.
A nonrenewable resource is a resource that cannot be reused or replaced in a useful amount of time. Many of the fuels we use for energy are also nonrenewable resources. Coal, oil, and natural gas are fuels. About 200 years ago, most people burned wood for fuel. One hundred years ago, coal provided almost all the energy used in the United States.