And to further the hijack, it looks like under the right conditions, He goes metalic.
ie, inside Jovian sized planets
Jesus is an X-Man?
Quite honestly, I suspect most elements go metallic under enough pressure, but only the smallest atoms allow for it under even astronomical conditions. I think that condensing the valence orbitals enough will turn them into an effective conduction band by making them overlap enough that the probability of an electron passing from one atom to another significant. Only the lowest MW elements though would have an electron repulsion low enough to make it possible though.
It’s just a guess though.
Yeah, it’s interesting how elements have a set of properties but when they combine with other elements, the nature of the new beast is something different. E.g. hydrogen and oxygen are gases at room temp, but H2O is liquid. Sodium and chlorine as elements could have some nasty outcomes if not handled properly, but you can actually EAT NaCl. Organic chemistry is crazy: Formaldehyde—CH20, has the same proportions of elements as fructose (C6H1206) but different properties fer sure.
BTW my doc recommends calcium citrate as a supplement instead of calcium carbonate. Wikipedia says Bioavailability is 2.5 times higher than calcium carbonate.