Irradiated gems typically are held until there is no residual activity remaining. Hobbyists who collect such things should vent the rooms in which these items are stored and be careful to avoid inhaling the fine dust particles from these samples. Some types of pottery are glazed with uranium oxide, such as Fiesta ware. To the best of our knowledge, this process has been discontinued, although some of these pieces are still in circulation. Positively charged particles emitted from the nucleus of an atom.
Alpha particles are relatively large, and very heavy.
A sheet of paper or an inch of air can usually stop most alpha particles. Beta particles have a mass and charge equal to that of an electron. Because of their light mass and single charge, beta particles can penetrate more deeply than alpha particles. A few millimeters of aluminum will stop most beta particles. A quantity of radioactivity in which one atom is transformed per second.