double terminated quartz crystals

I use with my HDR some double terminated quartz crystals to help increase power. There are those who wonder at me. Well, Steven Gibbs says that HDR works better when it uses quartz crystals in the witness well so that is what we use. There are many place to get double terminated quartz crystals, but I go to the psychic store to get mine. Quartz crystals should have sharp points at both ends for use.