[meteorite-list] Andi's Recrystallized NWA iron

[Mike Fowler]

> Hello Andi, Mike and List,
>
> Those interested in an iron that will be extremely difficult to  
> classify
> had better hurry because Andi is almost sold out. I am pleased I will
> soon own #17 and I've been brooding tonight over Andi's pics and Ted
> Bunch's preliminary description of that one-of-a-kind iron, its carbon
> rosettes, its granular kamacite, its iron, nickel, cobalt,  
> phosphorus and
> Si contents.
>
> I went through numerous Vagn Buchwald pages reading about and  
> looking at
> several pics of IIF irons trying to figure out what this new iron  
> might be.
> I re-read information about La Caille, but, ... nothing comes  
> really close
> to what this weird iron looks like. Can hardly wait to look at it  
> under my
> microscope and am eagerly waiting for final classification results  
> from
> Ted Bunch and other labs!
>
> This iron is so weird that even Ted Bunch is not sure yet whether  
> it should
> be classified as a IAB, a IIF or a IIICD iron!
>
> Best wishes,
>
> Bernd

I too bought one of Andi's slices.  Slice #13.

I read Ted Bunch's preliminary  analysis and it seemed like the Co  
content was way too low to be a member of the IAB group.  In fact in  
seemed low period.
I wish I had Metbase handy so I could make more comparisons.  Any  
else have an opinion about the Co content?

Mike Fowler
Chicago

ebay  starsandrocks

> Phase compositions via SEM EDS in weight percent:
>
>                 Fe          Ni          Co          P           Si
>
> Kamacite    91.4    7.4         0.45       0.4      0.32
>
> Taenite       67.4    30.6       0.13       0.13    0.22
>
> Bulk           85.5    14.2       0.21       0.35    0.27