It all depends on what you mean by "mine". Olympic Dam, the largest mining project on earth in not one mine, but many, all part of the same geological complex, an iron-oxide, copper, gold deposit (IOCG). It's so big that two towns had to be built to support it. It has both open pit operations and underground mining recovering many varieties of minerals including copper, precious metals, uranium AND rare earths.

Hay Mountain may not be an IOCG (though iron-oxide, copper and gold are present), but it may become the center of a complex of mining activity, vis-a vis what we had forseen for the Big Chunk Super Project, which, like the Tombstone area, is also a caldera-related cluster of targets.

So, while Hay Mountain itself may not be operating for a hundred years, assuming discovery, the other targets in the area could see work here-and-there over the next couple of centuries, if not more. ...certainly not all at the same points on the map, nor in same decades or centuries. But only dilling will answer these questions.

Is this more in line with your thinking?