When we were living in the upstate of SC, we took a field trip to an open pit mine that produces gravel for roads. That mine is a puddle size compared to the the 2nd and 3rd largest open pit mines in the world which are in northern Chile.
The largest is in Utah but the second largest is the Chuquicamata which is 1650 km north of Santiago near Calama in the Atacama Desert . It is 2,788 feet deep. It produces copper at 650,000 metric tons annually and also molybdenum and selenium.
The third largest open pit mine produces more copper at 750,000 metric tons and it is the Escondida Mine near Antofagasta. It is the largest copper producer in the world and also mines for gold and silver Chile provides 30% of the world's copper. The government owns the Chuqui mine. Copper prices are really high right now so that's a lot of money pouring into the Chile's coffers which is why the government has no debt!



And there is plenty more where that came from as you can read in this interesting article link below

http://www.thisischile.cl/2012/03/chiles-top-15-mines-hold-copper-reserves-for-another-century/?lang=en



"Chuquicamata-003 02" by Modified by Tennen-Gas - Image:Chuquicamata-003.jpg, photo by selbst fotografiert, created March 1984.. Licensed under Creative Commons Attribution-Share Alike 3.0 via Wikimedia Commons - https://commons.wikimedia.org/wiki/File:Chuquicamata-003_02.jpg#mediaviewer/File:Chuquicamata-003_02.jpg