Decay chain equilibrium is achieved, each successive daughter isotope is present in direct proportion to its half-life; but since its activity is inversely proportional to its half-life, each nuclide in the decay chain finally contributes as many individual transformations as the head of the chain, though not the same energy. For example, uranium-238 is weakly radioactive, but pitchblende, a uranium ore, is 13 times more radioactive than the pure uranium metal because of the radium and other daughter isotopes it contains. Not only are unstable radium isotopes significant radioactivity emitters, but as the next stage in the decay chain they also generate
Uranium tile still standing from that era by use of a simple geiger counter that readily detects the beta radiation emitted by uranium's ever-present decay chain radio-daughters. In most situations, the radiation exposure is not excessive, but there are some exceptions in which pure uranium oxide [which produces red-orange coloration as a glaze] on bathroom floors can pose a hazard for infants crawling around for hours on end, day after day. ORAU Radioactive Tiles Uranium tile Uranium tiles have been used in the ceramics industry for many centuries, as uranium oxide makes an excellent ceramic glaze, and is reasonably abundant on the