[meteorite-list] Strange Asteroids Baffle Scientists

[Darren Garrison]

On Thu, 23 Aug 2007 18:45:35 +1000, you wrote:

>>Is it not possible that one body may have an iron core that has a range
>>of nickel iron mixes thus producing several classes of iron meteorites
>>from the same source?
>
>I don't know that much about the various Irons, but what about IAB vs IIICD?
>Does anyone know?

You can google up more details than this thumbnail attempt at explanation, but
the "80ish parent body" determination is based on more than just the size/type
of nickel-iron crystals, it is based on the ratios of various trace elements and
isotopes present in the meteorite.  And the assumption is made that the elements
in the core would have been thoroughly mixed while the core was liquid.  So,
much like with stony meteorites, different elemental/isotopic ratios= different
parent bodies.  It is covered in some of the books on meteorites, but I can't
name which off the top of my head.