For various reasons, my house is full of crystals and I know what all of them do. I'm not going to say they're not helpful sometimes, either, just as I won't say they're helpful all the time. They're also pretty, so they make nice décor. My point is, I happen to know a lot about placing crystals in and around the house, and how doing so really can make your life a bit more balanced.
Do you spend a lot of time worrying about things? A little fluorite placed in the room where you can't shut off your mind – your office if you can't focus on work, your bedroom if you think too much when you're trying to sleep – can help you calm down, relieve your anxiety, and get out of a thought-rut.