Well, there is no doubt crystals resonate at certain frequencies. If they help for certain things or not I dont know anymore as I have various kinds of stones that I'v "tried" out but never gotten the feel of so to speak. I know that I can feel energy pretty strongly when I get new stones but then it disapears, almost as if Im absorbing the energy. For me, the stones tend to get weaker with time (and yes, I have energized them and all that ). Other than that, they are very nice to have around as they are pretty! I like them.