Re: [meteorite-list] New Arizona Meteorite!

[tracy latimer]

I can't say this with any definiteness, but I don't believe any "new" (i.e., 
unweathered) chondrules show signs of concentric layering, only ones that 
have been exposed to Earth's atmosphere and have suffered degradation from 
moisture.  I can't point to any example I have seen that shows anything like 
growth rings that have definitely formed outside Earth conditions; they all 
imply forming at once, rather than in successive buildups.  This completely 
ignores the question of armored chondrules, however.

Tracy Latimer
ON THE ORIGIN OF CHONDRULES
Norm and List,
Please excuse my ignorance for putting forth this question but as a 
relative "newbe" to meteorite collecting, I hope you will entitle me to 
this query.
I came across the term "accretionary lapilli" also called "volcanic 
pisolites" in Dorothy Ferris Lapidus 1987 edition of "The Facts on File 
Dictionary of Geology and Geophysics.
If you bear with me I'll quote " these are shperoidal concentrically 
layered pellets composed mainly of vitric dust and ash, usually between 2 
and 10 mm in diameter. They are formed primarily through the accretion of 
ash and dust by condensed moisture in eruption clouds. Formless nuclei of 
coarse particles fall through the fine debris and acquire shells of 
progressively finer ash. These concentric shells indicate the increasiing 
temperature and decreasing humidity of the cloud at lower levels.
My question is, does the process described above provide any 
anology("something similar but different") to the origin of chondrules.

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