Radon Testing Home › Forums › BigTrees Talk › Radon Testing This topic has 1 reply, 2 voices, and was last updated 9 years, 7 months ago by snowb0und. Viewing 1 post (of 1 total) Author Posts July 19, 2016 at 9:47 pm #4465 snowb0undParticipant It’s probably all the granite. Granite has some trace radioactive elements in it. Author Posts Viewing 1 post (of 1 total) You must be logged in to reply to this topic. Log In Username: Password: Keep me signed in Log In