[meteorite-list] New Meteorites Discovered in Australia

[David Weir]

Adam wrote:

Don't forget that NWA 3151 is definitely a Brachinite. All data was
submitted including the O-isotope results to the Meteoritical Society, 
peer reviewed and then voted on making it official. I checked with Dr. 
Irving again and he said that nowhere did he state that the NWA 3151 
classification status has changed or is likely to change.

Take Care,
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Hello Adam,

You're correct that Drs. Irving and Rumble didn't say that NWA 3151 is 
not a brachinite in their new abstract (#5288). What they did argue was 
that NWA 3151 is isotopically and petrologically similar to NWA 595 and 
NWA 4042, and that these three Saharan stones are not isotopically 
identical to Brachina. That said, it means that if NWA 3151 is indeed a 
true brachinite, then it follows that NWA 595 is the first true 
brachinite from the Sahara, in contrast to your advertising slogan for 
NWA 3151. Additionally, in their concluding statement, they suggested 
that "if all these specimens (including Brachina) derive from the same 
parent body, then it must be isotopically quite heterogeneous." (did you 
read that "if"?) From their data and discussion I feel that they are 
leaving the door open for a separate parent body for these Saharan 
brachinites distinct from Brachina. Their own data reveal a disparity in 
O-isotopes between Brachina and the rest of the Saharan brachinites, 
which is consistent with a separate parent body, just as it is 
consistent with a heterogeneous common parent body. I hope the former 
wins the day so I can add another new group to my collection 
(eventually). Thanks again Adam for the potential new group member 
(although I already do have NWA 595 and 4042).

Adam, I would appreciate you telling me how I haven't understood this 
abstract correctly, or you can pass this post on to your close friend 
Dr. Irving and maybe he can tell me what I have misunderstood. I'm 
always open for learning and I make corrections almost as often as I get 
something right. However, I thought I was getting pretty good at it 
after 12 years.

David (B.S. in Landscape and Ornamental Horticulture)