[meteorite-list] Polymict EUC vs. HOW - NWA1109 ? (& polymictdiogenites -NWA 1648)

[stan .]

>Jeff's comment about a contiuous but changing composition range of eucrites 
>to diogenites with Howardites in the middle made me also think that the 
>answer to Stan's question the other day when he was asking about his 
>diogenite pieces that look the same but one has vesicles. Could it just be 
>that the fall that generated those pieces was from a chunk of diogenite 
>that was at a transition zone close to a magam gas release that created the 
>vesicles in some of the material, but not in all of it. Sound like cool 
>stuff Stan.


my main question actually wasnt really about the fact that I have a 
diogenite with vessicals (something that is aparently undescribed in the 
literature) but rather the fact that I have a diogenite that is uniformally 
vessiculated throughout the stone. other stones from this find show no signs 
of vessicals. It just doesnt seem plausible to me that the same parent 
meteoriod would produce 1 stone totally vessiculated and a bunch that were 
not. the stones were all found within a stone's throw of each other, all 
have the same miro and macroscopic apearance, and are unbrecciated monomict 
diogenites... not exactly a common class of meteorite, so if this stuff ISNT 
the same material, it would be akin to finding two unrelated CI stones 
sitting right next to each other (and I'm NOT talking about finding such 
inside a dealers displaycase! :) ).

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