Magnetism
Magnetism is a class of physical phenomena that are mediated by magnetic fields. Electric currents and the magnetic moments of elementary particles give rise to a magnetic field, which acts on other currents and magnetic moments. The most familiar effects occur in ferromagnetic materials, which are strongly attracted by magnetic fields and can be magnetized to become permanent magnets, producing magnetic fields themselves. Only a few substances are ferromagnetic; the most common ones are iron, nickel and cobalt and their alloys. The prefix "" refers to iron, because permanent magnetism was first observed in lodestone, a form of natural iron ore called magnetite, FeO.
Bismuth
No other metal is verified to be more naturally diamagnetic than bismuth. (Superdiamagnetism is a different physical phenomenon.) Of any metal, it has one of the lowest values of thermal conductivity (after manganese, and maybe neptunium and plutonium) and the highest Hall coefficient. It has a high electrical resistivity. When deposited in sufficiently thin layers on a substrate, bismuth is a semiconductor, despite being a post-transition metal.Elemental bismuth is denser in the liquid phase than the solid, a characteristic it shares with germanium, silicon, gallium and water. Bismuth expands 3.32% on solidification; therefore, it was long a component of low-melting typesetting alloys, where it compensated for the contraction of the other alloying components to form almost isostatic bismuth-lead eutectic alloys.