Double Terminated Quartz Crystal

OK in HDR we use a double terminated quartz crystal to focus frequency. The idea is to concentrate power. Not sure how this works. However, we may see that HDR works better when using quartz crystals.

Personally, I feel the raw crystals from a mine in Arkansas are not as good as polished crystals I get over at the psychic store. These are more pretty quartz crystals than the raw.