Does anyone else use gems?

If anything, the power any gems could have to heal is actually the power of the person believing in them. Really, they are nice to look at, really pretty. I like gems and geodes and all that stuff, but... I don't think they have healing powers themselves. (Heh, I love magnetic rocks, so fun to play with. ) Anyways, isn't it sort of like those medical tests were they give the person sugar pills and they feel better because they think they're taking the real pill?