[meteorite-list] AD - A FEW DANDYS

[David Weir]

Hi Rob,

After absorbing most of the classification information that Jeff 
Grossman was so kind in providing to the list last Tuesday, I have found 
some inconsistencies in the information that you quoted on your webpage 
regarding NWA 2653. In the first case you quoted a source that grouped 
3133/1839/2653 together as paired. However, in the MetBull #89 Preview, 
NWA 1839 is officially classified as an L7, not an ungrouped PAC. Last 
time I looked at the NAU website this meteorite was also listed as an L7 
(it is curiously missing from their site today). Also, the implication 
was made that the O-isotope plot was the reason for the primitive 
achondrite designation rather than an L7 designation, but I don't think 
the O-isotopes have anything to do with this decision. Finally, your 
primitive achondrite NWA 2653 could not possibly be a CV7 as Jeff 
succinctly explained to us, these terms are mutually exclusive - 
primitive achondrites contain a melt component, at which point the Van 
Schmus-Wood scheme is no longer valid.

David (still in a learning mode)