> Bismuth was long considered the element with the highest atomic mass that is stable. However, in 2003 it was discovered to be extremely weakly radioactive: its only primordial isotope, bismuth-209, decays via alpha decay with a half-life more than a billion times the estimated age of the universe. Because of its tremendously long half-life, bismuth may still be considered stable for almost all purposes.<p>I learned something new -- Bismuth is technically radioactive.<p>Bismuth is probably my favorite element, because of the beautiful way it crystalizes and the beautiful colors it has. Beyond the beauty it's also remarkably non-toxic considering its siblings, a form of it is a useful medicine when traveling, and it's more dense as a liquid than a solid like water. It's a really fascinating element. I really recommend reading about bismuth, at least this article, since the article does a good job of explaining a lot of its interesting aspects.
"Bismuth's extremely long half life means that if the entire Earth was made of bismuth when it formed, less than one billionth of the bismuth would have decayed into thallium." What? Isn't it irrelevant how much bismuth you started with, if you measure it as a ratio??
Bismuth is also replacing (toxic) lead in shot (pellets) used for hunting, especially where there is evidence of lead poisoning in scavengers (like condors in California).