Average atomic weight: 207.2(1) u
| Isotope | Fraction | Atomic weight/u |
| 204 | 0.014(1) | 203.9730440(13) |
| 206 | 0.241(1) | 205.9744657(13) |
| 207 | 0.221(1) | 206.9758973(13) |
| 208 | 0.524(1) | 207.9766525(13) |
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)
