Half-life: 4,5 billion years
Main emission lines: 65, 95, 185, 750, 1001 keV
Uranium without radium refers to uranium that has been chemically processed or purified to remove its decay products, including radium-226. This separation minimizes the presence of isotopes in the uranium decay chain, particularly those that contribute to gamma radiation. The remaining uranium primarily consists of its natural isotopes: uranium-238 (~99.3%), uranium-235 (~0.7%), and trace uranium-234 (~0.005%). These isotopes primarily emit alpha particles, and the absence of radium significantly reduces the associated gamma radiation from uranium’s decay chain.
Purified uranium includes both weapons-grade uranium and depleted uranium, which are also free of radium. Weapons-grade uranium is highly enriched uranium, containing about 90% or more U-235, and is used in nuclear weapons due to its ability to sustain rapid chain reactions. Its purification ensures minimal radiation exposure from decay products, making it more practical for use in sensitive military applications.
Depleted uranium, on the other hand, is uranium that has most of its U-235 isotope removed during enrichment processes, leaving primarily U-238. Depleted uranium is significantly less radioactive and is used in applications such as armor-piercing munitions, radiation shielding, and counterweights in aerospace. Its lack of radium and other decay products reduces its gamma radiation output, making it safer for handling in these contexts.
Uranium (without radium impurities) is found in any uranium glass, Red Fiesta glaze, or reagents with uranium compounds.
Over time, radium will begin to accumulate, but it would take millions of years for the spectrum to take on the appearance of natural uranium.