This element has been known since the Middle Ages. Its name comes from the German weiße Masse (bisemutum).
Ionization energies
BiI 7.3 eV, BiII 16.7 eV, BiIII 25.6 eV.
Absorption lines of BiI and BiII
Bi has not been detected in the sun. Guthrie (1972) detected BiI in one Ap star of the Cr-Eu-Sr subgroup. Guthrie (1984) found the BiII 4259 line (W = 0.046) in one Bp star, of the Hg-Mn subgroup, and Cowley (1987) found this line in one Ap star of the Cr-Eu-Sr subgroup.
Isotopes
Bi has one stable isotope (Bi209), one (Bi208) with a half life of 3 × 105 years, an isomer with half life 3 × 106 years (Bi210) as well as 17 short-lived isotopes and isomers.
Origin
Bi can be produced by either the r or the s process.
Published in "The Behavior of Chemical Elements in Stars", Carlos Jaschek and Mercedes Jaschek, 1995, Cambridge University Press.