Metals of all types are important and valuable resources. Although their natural supply or the supplies of elements that go into producing various alloys are fixed, metals are highly recyclable and reusable. Metals, such as copper, tin, lead, aluminum, gold and silver, are elements. They are nonrenewable. Steel is are made from iron, which is also nonrenewable. Aluminum, iron and titanium are among the three most abundant elements in the Earth's crust. There are many benefits to recycling metals in addition to their cash value. Recycling them saves nonrenewable resources and reduces the need for additional mining.