An extinct volcano in Arkansas hosts the only public diamond mine on Earth

Fun! But not terribly significant. These kind of mines have been identified elsewhere, in quantity. Diamonds are no longer scarce.

E.g. https://www.youtube.com/watch?v=Do8IaDPTLlc

I have been several times and always enjoy the time spent there. I have never found a diamond but saw a woman cleaning her shoes find one. "Oh, what's this stuck to my shoe." So maybe it is not so hard finding diamonds, just not likely.