[meteorite-list] NWA 5363 UNGROUPED OR BRACHNITE

From: Jason Utas <meteoritekid_at_meteoritecentral.com>
Date: Sun, 25 Jul 2010 03:54:20 -0700
Message-ID: <AANLkTik4vtwtU_P0JiY+=0jW3XqQUcwDewrpiMDqYPri_at_mail.gmail.com>

Hello All,
Sorry - I've been a little out of things for the past few days. I
know I've got a few emails to get back to, and I'll get to 'em.

With regard to the original topic of this thread:
I addressed it before. Dr. Jambon has said that he studied the
meteorite and that NWA 5363 it is paired to NWA 5400. The question of
the pairing itself should not be a topic that we debate. *If* someone
has reason to believe that Dr. Jambon is lying, or have any reason to
question his methodology, he or she should voice his or her opinion
clearly and without reserve.

If we are going to consider it seriously, this discussion needs to
revolve around the credibility of Dr. Jambon. The people claiming
that he is lying about NWA 5363 have suggested that he is not a
creditable scientist; in a sense, the thing being questioned here is
not the pairing itself.

If, on the other hand, this is going to be a topic that centers on
what information is required to determine whether or not two
meteorites are paired, that's another discussion entirely. I suggest
we split this thread into its respective components, because I don't
think that arguing two or three things at once is going to reach any
coherent conclusion.

And...
I know the stone of which Elton is speaking, and I know of whom he is
speaking.

And it was an ordinary chondrite found in Nevada (not a complete stone
- a broken fragment with one or two sides of weathered fusion crust),
comprised of, as he said, a number of fragments.
Yes, I have photos of it stored from Bob's ebay auction.

I would like to point out three things:

1) Isotopic/CRE/depth observations are almost never performed on such
meteorites (small, solitary ordinary chondrites). Large falls such as
Allende and Holbrook - and large finds such as Gold Basin, Franconia
(I don't think such a study was even done on Franconia (!)), etc, are
the typical candidates. I know of no other stones found in the
southwest for which this type of study was done, so, while you can
lament the fact that it is now too late to do it, it would not have
been done anyways. It's not worth it for individual small finds,
because there's simply little observed difference between CRE data
over the ~two inches in depth that a given 2-300g stone covers.

2) There are many such meteorites that were found fragmented and
subsequently put together - and that were then distributed. If you
choose to disregard every fall and find from before the advent of the
technology that allows us to make such observations of CRE data, there
are still many, many examples. Many of the stones from the southwest
are found in such a manner - we've found at least ten or twenty of
puzzles ranging from two to ten or so pieces. 17's high for the
number of fragments, but - see point number three.

*I can post some photos if you'd wish - some are quite pretty, and I
don't have too many up at the moment. See below for such a grouping
of fragments that later fit together to form a whole stone (see later
photos in the stream for a few more from that cluster).

http://picasaweb.google.com/MeteoriteKid/PersonalFinds#5418954643038454866

8 fragments were found here - we stopped looking after finding seven,
put the stone together, and realized there was still a piece missing -
for some reason, it alone was fifteen or so feet away from the others
(exact number recorded, not on hand). Oddly enough, that solitary
fragment was sitting in our tyre track from when we'd arrived at/were
driving onto the lakebed earlier that morning.

3) The stone in question was a ~2-300g stone. You're not going to get
a meaningful range of depths from CRE data within the parent body data
because all of those data points (the 17 fragments) are all from the
same small stone. They were in the same place in the parent body. If
you were to use one fragment for study, you would already know that
all of the others came from about an inch or so away, at most. You're
not going to get that much meaningful data from it because it's
essentially all one data point.

If you wanted to calculate the size of the body before it entered the
atmosphere, you'd be better off looking at two fragments from
different stones, because that's when you would see a range of depths
from within the pre-atmospheric mass (hopefully). Well, it's best to
get as many stones as possible (you're more likely to get useful
data), but two is better than one.

I agree, it was a pretty stone, and a real shame to part the pieces of
a stone like that, for aesthetic reasons.
I wouldn't do it. But as I said with Joe Kerchner and his recent
find, it's his right to do it, whether or not I approve.
(The only reason I posted then was because of the lofty language that
was being used to describe the find, which was subsequently diced and
broken up because he was in need of the money it would bring.)

Scientifically there was no real loss: at least, any more than there
is when anyone cuts a stone up for any reason other than analysis.

But...this happened something like five years ago. Seems a bit out of place.

Also -

>DESTROYING the scientific rarity

Science cares not for rarity, unless it's a question of being able to
get a sample to study.
It's we collectors who think that rarity is what makes a meteorite
interesting. It's why we pay hundreds of dollars per gram for
ordinary chondrites when the same material (chemically/physically) is
available for cents per gram - or at most a few dollars per gram for a
nice fresh stone. An L6 is an L6, after all. Well, not quite - from
what I've read, Mont Tazerzait is likely from a different parent body
than most other L's...but it's not a type 6 anyways. It's an L5.

http://www.meteoritestudies.com/protected_MTTAZ.HTM

A chondrite from a new parent body! Very few representatives, and
it's usually only a few dollars a gram! But I think this is a case of
ignorance - I doubt many people even know about this aspect of this
particular meteorite, since it's "just an L5."

Best,
Jason

On Sun, Jul 25, 2010 at 1:41 AM, Barry Hughes <bhughes at sneezy.com> wrote:
> On Sun, Jul 25, 2010 at 4:37 AM, Barry Hughes <bhughes5551 at gmail.com> wrote:
>> You can see...I don't know this. ?I do know that research for new and
>> old find is utmost importance..I can understand that.
>> I don't know the particulars and should maybe keep my mouth shut, but
>> I can tell you that for the uninformed, this bickering is not the best
>> thing for the new collector.
>> The List should maybe be something someone follows later in their hobby ...like finally learning your beautiful girlfriend does actually
>> take a shit sometimes...:)
>>
>> On Sun, Jul 25, 2010 at 2:02 AM, MEM <mstreman53 at yahoo.com> wrote:
>>>
>>>
>>> ----- Original Message ----
>>>
>>> ?The people about to make a lot of ?money..or not..don't paint a pretty picture
>>> here...
>>> ?Is this what the list is ?about?
>>>
>>>
>>> Nope. ? Nor is it what the thread is about.
>>> Money could be an artifact of the outcome but the issue of scientific pairing is
>>> two fold:
>>> Paring legitimizes interchangeable research using a sample from either stone.
>>> Pairing does not skew the data plots for composition/chemistry/etc by counting a
>>> sample more than once.
>>> ( I know this will shock some here to learn that meteorites are not just
>>> fashionable collectibles but are in-fact used in scientific research--Who'd a
>>> thought, eah?)
>>>
>>> The converse is that uninformed and unscientific "visual pairing" does not
>>> satisfy the requirements of the above needs.
>>>
>>> On the commercial issue, it is a long and costly process to do meteorite
>>> petrology-- most always paid for by one of the owners. ?To be paired the
>>> chemistry/petrology of all named meteorites must be researched to establish
>>> compelling evidence of pairing. ?Exceptions: a meteorite fall on a area known to
>>> contain no other meteorites, the stream of visually identical debris which is
>>> recovered in a short time, or the stones can be physically matched--these can be
>>> presumed to be paired unless tere is evidence to the contrary.
>>>
>>> Claims of pairing which are not scientifically validated is akin to plagerizing
>>> and is taking both scientific and commercial value from another who did go
>>> through the process.
>>>
>>>
>>> In "reverse pairing" or "unpairing" there is one atrocity that I still am
>>> disgusted over: a meteorite find was recovered over an area. ?It was entirely
>>> reassembled to compose a complete meteorite: ?known as the "meteorite puzzle".
>>> This is the only known case in history. Were it kept together, a lot of research
>>> could have been done-- cosmic ray penetration, shear stress, understanding why a
>>> particular meteorite fragmented into 17 pieces, and etc. ?But some self-styled
>>> meteorte dealer wannabe--(wait maybe this was while he was a non dealer? ?Nope!
>>> This was while a dealer)--whatever-- ?he so "loves" meteorites being "shared"
>>> that he bought the Puzzle for his collection-- never to ever sell it he assured
>>> the seller. ?Then he promptly put all 17 pieces on ebay as individual auctions
>>> to be sold to 17 different buyers--DESTROYING the scientific rarity.
>>>
>>>
>>> Elton
>>>
>>>
>>
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Received on Sun 25 Jul 2010 06:54:20 AM PDT