On the 11th June, 2012, I took delivery of some mildly radioactive rocks from Nighthawk Minerals. I put the ziplock bags of radioactive 'mud' under my sheets, hung the pendant rock around my neck, and put the waterstone in a approx. 1.6 litre water jug in my fridge. Since then I have filled water bottles (about 4) each morning from the water jug for drinking through the day, and kept the pendant on most of the time - except when showering or running. What is so interesting is that, since then, I have not had the usual two or three colds and or sore throats per year. I recently travelled to England via jet, a circumstance previously almost guaranteed to make me sick. I did get some very mild cold and sore throat symptoms, but these disappeared after about four days. That was June 2013. As I live in a location where people travel worldwide and come back (truly a 'United Nations' type of community) and other people here always seem to be getting sick, I feel my experiment has been validated. I am convinced that the slightly elevated background radiation levels I now experience are generating a kind of 'vaccination' effect.... and I love it! Chris Davey, 23rd August 2013P .S. I added to the effect in February 2013, by getting a set of five radiant beads from Ian Soutar - this boosts my very slightly elevated radiation field a little more (at least it does in the area within a few centimetres of my upper chest, as that is about the limit of the effective range of the elevated field from such small sources).