Mmm. Yes, in the sense of infusions. Just make sure anything soaked isn't poisonous. Like with the gems, make sure they don't release anything in the water that's toxic.
Personally, I wouldn't make anything to ingest beyond store bought tea. I would stick with things I could sprinkle around the house or wash with. Since it's making contact with skin, still be careful of irritation. An easy way to do it would be putting the herbs and stuff in a coffee pot.