Sustainability of Earth Resources

Fossil fuels are not the only Earth resource we rely on in great quantities. Over 1.5 billion cell phones are made yearly; each using 64 different elements, at least 12 of which are currently irreplaceable. Iron, copper, nickel, rare earth elements, and even sand, are all key components of our modern world that we extract from the Earth. How much are left? How environmentally damaging is it to extract them? Are there alternative extraction methods, or alternative materials? Can they be recycled? What part of your world would you be willing to give up to reduce environmental impacts?