Uranium-238 vs. Uraninite (and Natural Background) Radioactivity

Here is a less blurry but still HOT video in which I compare the radioactivity of the natural background (cosmic rays and other unavoidable environmental sources) to pure uranium-238 to that of a crystal of the mineral uraninite (uranium oxide). The result is counterintuitive, but can be explained by the fact the uraninite is immensely old, and contains the decay products of uranium, including a tiny bit of radium and other short-lived, continually-replenished radioactive daughter products. And radium is far more radioactive than uranium-238. (Oops, I gave away the surprise!) In addition, I give an indication as to why I can (sanely) have this stuff in my dwelling. Take a look...you'll see! (But never store radioactive sources near sleeping or eating quarters, and always thoroughly wash your hands after handling them!)