In the depths of the earth there is a web of tunnels where human industry uncovers the most basic elements. In chasms, they find minerals and metals from copper and iron to zinc and aluminum.
The passages remain a mystery to most of us. But not to students at the University of Arizona.
I am descending into the dusty depths of the University’s San Xavier Mining Laboratory. On the ladder below me is Chris Zanin, a sophomore in the Department of Mining and Geological Engineering.