Also, a note on the humanitarian side of things, but not directly related to mining: When the Portuguese colonies seceded in the 70s, many people returned or emigrated to Portugal with nothing more than the clothes on their backs and "diamonds" they had exchanged their farms and real estate for.

I remember a few dinner conversations about how a few of them came to my father to assess the value of those stones, and most were chunks of quartz or other worthless crystals.

I think some of those conversations were really tough, and one of the reasons he disconnected from work as much as he could (his hobby was electronics, and one of the reasons I got into computers was that he brought a Sinclair ZX81 from London after years of putting together various kits, including a HeathKit oscilloscope).

So, in a way, diamonds are the reason I do what I do these days.