Isotopes of rutherfordium

Rutherfordium (₁₀₄Rf) is a synthetic element and thus has no stable isotopes. A standard atomic weight cannot be given. The first isotope to be synthesized was either ²⁵⁹Rf in 1966 or ²⁵⁷Rf in 1969. There are 16 known radioisotopes from ²⁵³Rf to ²⁷⁰Rf (3 of which, ²⁶⁶Rf, ²⁶⁸Rf, and ²⁷⁰Rf, are unconfirmed) and several isomers. The longest-lived isotope is ²⁶⁷Rf with a half-life of 48 minutes, and the longest-lived isomer is ^263mRf with a half-life of 8 seconds.