17-12-2021, 09:31 PM
In the '80s I was involved in the manufacture of tyre valves for earthmoving equipment. I remember a trip to the Kennecott copper mine in Utah where they were using dozens of 500 ton dump trucks. Quite an experience especially standing next to them in the maintenance sheds. The mine was so large that these trucks at the bottom of the mine looked liked Matchbox toys. The owners budgeted to loose an average of 2.5 trucks a year over the sides of the mine. It was said that the precious stones found during mining paid for the facility leaving the copper as 100% profit.