Radioactivity Counter App (i Phone Android) and Geiger Counters measuring Thorite Crystal

Measuring a rare cut thorite crystal (Th, U)SiO4 from my private collection of active minerals. The crystal emits mainly β and γ rays. You can see various blocking materials utilized, like cardboard, Pb, Cu and plastic. Even the direct exposure has some layers of ducktape as blockingmaterial (measuring β + γ to 48, 5 µGy, h a realistic amount), that are prerogative for the correct function of the App. The russian SOEKSCounter and GeigerCounter are included for comparison. Note the difference b br,