I came across some interesting information about the element Bismuth:

"No other metal is verified to be more naturally diamagetic than Bismuth. It is the most diamagnetic of naturally occuring elements."

"Because bismuth is the most diamagnetic naturally occurring element, it is used for diamagnetic levitation."

 

Can someone supply an understandable explaination, or a reference to an understandable explaination, as to why bismuth is the most diamagnetic of naturally occuring elements?

And to make the question of more interest than the answer that one might be able to supply from a textbook: would molten (liquid) bismuth exhibit the same diamagnetic properties as is exhibited by its solid crystaline form?

I doubt it matters but the question is in the wrong place. Diamagnetism is a quantum effect.

I don't know why Bi is so diamagnetic, but I do know that it stops being if you melt it.

That means that part of the reason must be the crystal structure and Bi has a very odd structure.

Pyrolytic carbon (an other element but not a metal) is more strongly diamagnetic than bismuth

http://en.wikipedia.org/wiki/Diamagnetism

 

More generally, magnetism is a molecular property, not an atomic one, so melting changes everything. For instance CrO₂ is a permanent magnet and was used on magnetic recording tapes but neither Cr nor O is ferromagnetic. Ferrites used in electrical engineering comprise Zn and Mn to be ferromagnetic. Austenitic stainless steel is not ferromagnetic despite being made of Fe and Ni mainly.

See also

http://en.wikipedia.org/wiki/Heusler_alloy