Re: [meteorite-list] NWA R-chondrite pairings
Hello John and List, John wrote: Can anyone tell me if any of the different numbered NWA R-chondrites are paired? Like NWA 753 and 978, both R3.8's...and also NWA 782 and 800...both R4.0. Along with Ouzina...also a R4.0. I will try to answer your question. NWA meteorites are always a little controversal so hopefully the list will go nice on me. I believe NWA753 is paired with the "non-magnetic" NWA you purchased from Dean. The total weight reported on NWA753 is 12 kilos but I would guess it to be in the fashion of 30 kilos. There is more of it in Morocco right now and the sellers know what it is. Much have the meteorite has also entered the market since its original purchase. Pairing is often done without report to the Meteorite Society, such is the way with NWA's. NWA753 and NWA978 may possibly be paired. On the R4's, I do not know. It would be nice to have CRE age comparisons done on these stones. They do as you noted look very simular but you would exspect such from an R3.8, R3.9 and an R4. R chondrites are rare, unbrecciated R chondrites are ever more rare. The reason why we have so many from Morocco leaves the chance they might be the same stone. However, at the prices the R chondrites are currantly being sold you really can't go wrong. I am sending this to Dean also, since he is no longer a list member. If he would like to comment on the subject I will post his comment later this evening. Mark Bostick __ Meteorite-list mailing list [EMAIL PROTECTED] http://www.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] NWA R-chondrite pairings
Dear John I posted a very similar message about 6 months ago, without great success... So here is my personal feeling: it looks unlikely statistically that two different R3.8 or R4 come out of NWA, but not impossible : there are 2 nakhlites and 4 shergottites in NWA. It is true that 753 and 978 or 800 and Ouzina show different weathering and "colors", but this happens on different pieces of the same fall. What I would bet very highly unlikely is that more than 2 different R3.8 or R4 exist! No type of detailed study can solve the problem definitely, as even if every chemical and petrographic features would be the same in 753 and 978 for example, it does not tell for sure that they are the same fall: they may be different fall from the same "asteroidal outcrop"; there are many examples of that in ordinary chondrites (undistinguishable different falls). Once again we touch the major drawback of NWAs: no precise location means unsolvable incertitude in pairing. We can just talk about probability and with the squeletic R population, statistics are nearly meaningless. (My unconvinced bet is that 753 and 978 are the same fall, but I would not be surprised of the opposite) Pierre __ Meteorite-list mailing list [EMAIL PROTECTED] http://www.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] NWA R-chondrite pairings
Hello all, On to new subject. Can anyone tell me if any of the different numbered NWA R-chondrites are paired? Like NWA 753 and 978, both R3.8's...and also NWA 782 and 800...both R4.0. Along with Ouzina...also a R4.0. The reason I asked is because I was one of the curious to recently buy a "non-magnetic" NWA meteorite offering from Dean. I received it this weekend and it looks just like a fresh slice of 978 I got from the Hupes. Very nice...but unclassified I suppose. Just curious about pairings...maybe it is not known and yet to be studied, John
