Not to defend these things, I also don't think they work, but the simplest argument is that they work on a metaphysical frequency/energy/whatever, so a physical instrument wouldn't be able to detect it.

Could also be a placebo which has been clinically proven to have some subjective effect. Not worth getting fleeced over, but worth 2 bucks for a nice rock that makes you feel hopeful.

When I was growing up (granola) everyone in my family had a special little crystal that represented them. I remember when we all picked them out from a big bin. Not to say this kind of thinking can’t have a dark side, though…

Nowadays I just find “special” rocks while I’m out on a walk feeling a certain way, and like mentally imbue them whatever feeling I need (stability, remorse, etc). Then I keep them around and think of that whenever I look them, until I eventually forget why I even got them.

Got a nice Jasper that’s flat on one side helping me through some shit with my family atm