So without going into heaving TLDR details, as I said, this days I'm semi-retired and spend most of my time either planning prospecting and/or treasure-hunting trips, or going on the planned prospecting and/or treasure-hunting trips.
I've already talked a little about prospecting (focus on Nevada and a tiny, tiny bit on that part of California that is right next to Nevada - but I'm much more familiar with Nevada Regs regarding prospecting than Cali)
With respect to treasure-hunting I focus on two things Confederate treasures troves and the closely related Knights of the Golden Circle treasure troves. There are a lot of these troves still to be found (though, unsurprisingly, most are in former CSA states) and I find researching and looking for them far more interesting than playing MMOs these days. As prospecting IRL is more interesting than Minecraft, so too, looking for treasure troves IRL is far more interesting than playing Everquest or Vanguard.
If any of you are interested - I'll give you a few basic pointers about researching KGC treasure. You need access to old newspapers (microfilm most likely) of 1865 to 1885 or so (the period when KGC was most active). You're looking for weird articles similar to the following:
But you need the whole newspaper page not just an excerpt like this and the article may not be about treasure specifically (as this one is) but will usually contain words like 'key' 'lock' and a lot of numbers. I have another example but I can't find it right now. If I find it, I'll post it.
if you find an article like this from the correct time period, I can give you some suggestions on how to properly decode it to figure out the location they're referencing -- for a split ;-). I can't and won't guarantee that I can decode it but I can give it a pretty good go, I have a decent working familiarity with some common Confederate and KGC ciphers at this point.
Cheers