Ladies & gentlemen, & yes, you also trucker: I received a pm asking if jim's - la Yesca - closed mine and mine were the same. No, they are not. They are separated by almost half of Mexico.
I merely mentioned it to show that Yes, there are hidden mines, hidden, or abandoned, for various reasons.
Since Jim's is in a producing field, I suspect that it can be considered as positive news.
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Don Jose de La Mancha