Bismuth

from The STEMcell Science Shop

Regular price $24.00

Bismuth is one of the pure chemical elements (Bi, 83) and a metal with many unique properties. It is almost as dense as lead, but without the toxicity. It is also one of the least thermally conductive metals, but has a relatively low melting point (271°C, 520°F). In fact, when melted, bismuth can crystallize upon cooling into the stair-stepped pattern. The iridescent colors are caused by the oxidation of the outer layer as it cools.

 

More info:

Bismuth was recently discovered to be very weakly (harmlessly) radioactive. But since its half-life is longer than the age of the universe, it can be considered stable. Bismuth is a key ingredient of Pepto-Bismol. You can even extract it from the pink medicine with a little chemistry.