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
Beverley Uranium Mine The uranium mineralisation (mainly coffinite) is hosted by loose sands in the channel of a former river. The ore bearing horizon is now at a depth of about 100 to 150m. The deposit is estimated to contain 21,000 tonnes of uranium oxide for a mine life of 15 to 30 years. Uranium is extracted by in-situ leaching, involving the injection of a fluid containing sulphuric acid and hydrogen peroxide into the ore-bearing permeable horizon to mobilise the uranium. The fluid is then recovered and uranium is extracted at a central plant using ion-exchange. The final concentrate is trucked to Port