[meteorite-list] No nickel-free iron meteorites

[Matson, Robert D.]

Hi Carl,

Alan wrote:

> "Please note that volumetrically, the amount of low-Ni metallic Fe is
> trivial, far less than 0.1% of a typical chondrite."

You replied:

> ".1% is a relative term. Earth may be only a fraction of the size of
> Artares [Antares] but, it is still a pretty big rock."

I don't think you're quite absorbing what Dr. Rubin is saying. There is
no
natural solar system mechanism that can separate iron from nickel in
macroscopic quantities. So if you find a lump of iron on earth that
doesn't
have nickel in it, it originated here. It is not a question of there
being
room for reasonable doubt. It simply cannot happen. The physics of
nucleosynthesis, cosmochemistry, and entropy do not allow it.

Best,
Rob