(this element has radioactive isotopes that survive on geological/cosmological timescales)
Average atomic weight: 238.02891(3) u
| Isotope | Fraction | Atomic weight/u |
| 234 | 0.000054(5) | 234.0409523(19) |
| 235 | 0.007204(6) | 235.0439301(19) |
| 238 | 0.992742(10) | 238.0507884(20) |
Atomic weights and isotopic compositions were obtained from NIST Database 144
The Atomic Line List does not contain any data for this element
(Atomic Line List v3.00b5)
