Bismuth is a chemical element with symbol Bi and atomic number 83. Bismuth, a pentavalent post-transition metal, chemically resembles arsenic and antimony. Elemental bismuth may occur naturally, although its sulfide and oxide form important commercial ores.
Three reasons Bismuth stands out
- 1
Non-toxic metal with a beautiful rainbow-colored surface.
- 2
The active ingredient in the pink stomach medicine Pepto-Bismol is a compound of this metal.
- 3
Although technically radioactive, its most stable isotope has a half-life roughly a billion times longer than the age of the universe.
The rainbow metal with a nearly eternal isotope
Bismuth crystals grow stepped shapes and acquire iridescent oxide films that create their familiar rainbow colors. The element is far less toxic than neighboring lead and appears in medicines and low-melting alloys. Bismuth-209 is radioactive, but its half-life is vastly longer than the age of the universe.