[meteorite-list] AD - A FEW DANDYS

[Rob Wesel]

Hi David

The NAU website listed 1839 as a pairing, I will look and see now if it 
should be removed from the description. It sounds like it should come the 
publishing of MetBull #89 if the classification holds. That is easy enough 
to do.

I agree with your assessment that the two classifications are mutually 
exclusive which is why I have it listed at the top of my page as a PUA. One 
can not deny, however, the fact that CV has come up as a POSSIBILITY given 
that O-isotopes plot on the CV mixing line. I agree, it is one or the other 
and for now the official classification is PUA with the very enigmatic 
isotope data. I don't claim it to be, though I mention the possibility 
several times, a CV7. It is in my opinion doubtful that any scientist will 
take an official position to that end, but science continues on it and 
perhaps one day the isotope data will be further hypothesized.

Does my description talk in circles, yes, but the scientists that studied 
this and made the classification made the CV caveat.

Rob Wesel
http://www.nakhladogmeteorites.com
------------------
We are the music makers...
and we are the dreamers of the dreams.
Willy Wonka, 1971



----- Original Message ----- 
From: "David Weir" <dgweir at earthlink.net>
To: "Rob Wesel" <nakhladog at comcast.net>
Cc: "Meteorite List" <meteorite-list at meteoritecentral.com>
Sent: Friday, May 20, 2005 3:48 PM
Subject: Re: [meteorite-list] AD - A FEW DANDYS


> 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)
>
>