Gold could do the same. But it is sad to see an institution like the South African gold mining industry slow down and slip away. It once was upstanding and proud, the best in the world. Approaching West Driefontein when I worked there many years ago, you could see the headgear from miles away. But when I returned last year, it was a scruffier place, not like the sparkling industrial giant it had once been.
All miners know there is a limit to every discovery.
It's one of the rules of mining. The excitement is in making a new discovery.